1
|
Hindurao B, Gujare A, Jadhav H, Dhatrak P. Evaluate the effect of bone density variation on stress distribution at the bone-implant interface using numerical analysis. Proc Inst Mech Eng H 2024; 238:463-470. [PMID: 38534009 DOI: 10.1177/09544119241240940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
The current study aims to comprehend how different bone densities affect stress distribution at the bone-implant interface. This will help understand the behaviour and help predict success rates of the implant planted in different bone densities. The process of implantation involves the removal of bone from a small portion of the jawbone to replace either a lost tooth or an infected one and an implant is inserted in the cavity made as a result. Now the extent of fixation due to osseointegration is largely dependent on the condition of the bone in terms of the density. Generally, the density of the bone is classified into four categories namely D1, D2, D3, and D4; with D1 being purely cortical and D4 having higher percentage of cancellous bordered by cortical bone. A bone model with a form closely resembling the actual bone was made using 3D CAD software and was meshed using Hyper Mesh. The model was subjected to an oblique load of 120 N at 70° to the vertical to replicate occlusal loading. A finite element static analysis was done using Abaqus software. The stress distribution contours at the bone-implant contact zone were studied closely to understand the changes as a result of the varying density. It was revealed that as the quantity of the cancellous bone increased from D1 to D4 the cortical peak stress levels dropped. The bone density and the corresponding change in the material characteristics was also responsible for the variation in the peak stress and displacement values.
Collapse
Affiliation(s)
- Bhargav Hindurao
- Department of Mechanical Engineering, Dr Vishwanath Karad MIT World Peace University, Pune, Maharashtra, India
| | - Aditya Gujare
- Department of Mechanical Engineering, Dr Vishwanath Karad MIT World Peace University, Pune, Maharashtra, India
| | - Harshavardhan Jadhav
- Department of Mechanical Engineering, Dr Vishwanath Karad MIT World Peace University, Pune, Maharashtra, India
| | - Pankaj Dhatrak
- Department of Mechanical Engineering, Dr Vishwanath Karad MIT World Peace University, Pune, Maharashtra, India
| |
Collapse
|
2
|
Wang L, Meloro C, Fagan MJ, Kissane RWP, Bates KT, Askew GN, Watson PJ. Regional variation of the cortical and trabecular bone material properties in the rabbit skull. PLoS One 2024; 19:e0298621. [PMID: 38412158 PMCID: PMC10898762 DOI: 10.1371/journal.pone.0298621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 01/27/2024] [Indexed: 02/29/2024] Open
Abstract
The material properties of some bones are known to vary with anatomical location, orientation and position within the bone (e.g., cortical and trabecular bone). Details of the heterogeneity and anisotropy of bone is an important consideration for biomechanical studies that apply techniques such as finite element analysis, as the outcomes will be influenced by the choice of material properties used. Datasets detailing the regional variation of material properties in the bones of the skull are sparse, leaving many finite element analyses of skulls no choice but to employ homogeneous, isotropic material properties, often using data from a different species to the one under investigation. Due to the growing significance of investigating the cranial biomechanics of the rabbit in basic science and clinical research, this study used nanoindentation to measure the elastic modulus of cortical and trabecular bone throughout the skull. The elastic moduli of cortical bone measured in the mediolateral and ventrodorsal direction were found to decrease posteriorly through the skull, while it was evenly distributed when measured in the anteroposterior direction. Furthermore, statistical tests showed that the variation of elastic moduli between separate regions (anterior, middle and posterior) of the skull were significantly different in cortical bone, but was not in trabecular bone. Elastic moduli measured in different orthotropic planes were also significantly different, with the moduli measured in the mediolateral direction consistently lower than that measured in either the anteroposterior or ventrodorsal direction. These findings demonstrate the significance of regional and directional variation in cortical bone elastic modulus, and therefore material properties in finite element models of the skull, particularly those of the rabbit, should consider the heterogeneous and orthotropic properties of skull bone when possible.
Collapse
Affiliation(s)
- Linje Wang
- Structural Biomechanics, Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
- School of Engineering, University of Hull, Hull, United Kingdom
| | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Michael J Fagan
- School of Engineering, University of Hull, Hull, United Kingdom
| | - Roger W P Kissane
- Department of Musculoskeletal & Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Karl T Bates
- Department of Musculoskeletal & Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Graham N Askew
- School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
| | - Peter J Watson
- School of Engineering, University of Hull, Hull, United Kingdom
- Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds, United Kingdom
| |
Collapse
|
3
|
Phusantisampan P, Chaiworawitkul M. Cortical Bone Thickness and Morphology at the Infrazygomatic Crest Area in Growing Thai Patients with UCLP: A CBCT Study. Cleft Palate Craniofac J 2024:10556656241228738. [PMID: 38291624 DOI: 10.1177/10556656241228738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024] Open
Abstract
OBJECTIVES To determine and compare buccal cortical bone thickness and morphology (in terms of shape and height) at the infrazygomatic (IZ) crest in growing Thai patients with unilateral cleft lip and palate (UCLP) using cone-beam computed tomography (CBCT) with the ultimate goal of identifying potential sites that are suitable for the placement of miniplates. DESIGN Prospective study. SETTLING Institutional research. PATIENTS Twenty-four Thai patients with non-syndromic complete UCLP with Class III skeletal discrepancy aged 10-14 years. INTERVENTIONS A total of 48 CBCT images captured the IZ crest. Five horizontal and six vertical reference planes were established in the IZ crest area. MAIN OUTCOME MEASURE The mean buccal cortical bone thickness of the cleft and non-cleft sides were 1.13 ± 0.45 mm and 1.15 ± 0.46 mm, respectively. The most frequently observed shape for the IZ crest was the external concave contour. There were no statistically significant differences in cortical bone thickness and shape distribution between the cleft and non-cleft sides. (P > .05). RESULTS The thickness of the buccal cortical bone increased anteriorly and superiorly from V + 0 and H + 0. The average height of IZ crest on the cleft side was 16.20 ± 1.59 mm and 16.78 ± 1.84 mm on the non-cleft side. Notably, significant differences were detected in terms of height between the cleft and non-cleft side and cortical bone thickness by gender (P < .05). CONCLUSIONS The IZ crest was found to provide sufficient support for the insertion of a miniplate, particularly in the superior and anterior regions, ensuring primary stability in growing Thai patients with UCLP.
Collapse
Affiliation(s)
- Ploypailin Phusantisampan
- Division of Orthodontics, Department of Orthodontic and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | - Marasri Chaiworawitkul
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| |
Collapse
|
4
|
Álvarez A, Correa SA, Buschang PH, Roldán SI. How does arch form and interproximal contact size affect the 3D displacements and rotations of teeth: a finite element analysis. Dental Press J Orthod 2024; 28:e232381. [PMID: 38198350 PMCID: PMC10768646 DOI: 10.1590/2177-6709.28.6.e232381.oar] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 10/09/2023] [Indexed: 01/12/2024] Open
Abstract
OBJECTIVE The objective of this study was to determine how arch form and interproximal contact size displace mandibular teeth subjected to an anterior component of force (ACF). METHODS Nine finite element models (FEM) of the mandibular arch were developed using Ansys® v. 16.0 software. They were designed to evaluate the effects of three arch forms (triangular, oval, and square) and three contact sizes (point-to-point, 1 mm diameter, and 2 mm diameter). All nine models were subjected to an ACF of 53.8 N (5486 gm). Three-dimensional tooth rotations and displacements of the mandibular teeth were evaluated, from the right first molar to the left first molar. RESULTS Arch form had a greater effect on tooth movements than contact size. Triangular arches and point-to-point contacts produced the greatest displacements and rotations of teeth. Oval arches with 2 mm wide interproximal contact points showed the greatest stability. The right first premolar showed the greatest displacements in all of the models. CONCLUSIONS Arch form and contact size affect interproximal tooth stability. Teeth are least stable in narrow arches with point-to-point interproximal contacts, and most stable in wider arches with larger contacts.
Collapse
Affiliation(s)
| | | | - Peter H Buschang
- Texas A&M University Baylor College of Dentistry, Orthodontics (Dallas/Texas, United States)
| | | |
Collapse
|
5
|
Menke C, Kluge M, Welke B, Lenarz T, Majdani O, S. Rau T. Pull-Out Strength of Orthodontic Miniscrews in the Temporal Bone. J Otolaryngol Head Neck Surg 2024; 53:19160216241248669. [PMID: 38903014 PMCID: PMC11191615 DOI: 10.1177/19160216241248669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/07/2024] [Indexed: 06/22/2024] Open
Abstract
BACKGROUND Minimally invasive cochlear implant surgery by using a microstereotactic frame demands solid connection to the bone. We aimed to determine the stability of commercially available orthodontic miniscrews to evaluate their feasibility for frame's fixation. In addition, which substitute material most closely resembles the mechanical properties of the human temporal bone was evaluated. METHODS Pull-out tests were carried out with five different types of orthodontic miniscrews in human temporal bone specimens. Furthermore, short fiber filled epoxy (SFFE), solid rigid polyurethane (SRPU50), bovine femur, and porcine iliac bone were evaluated as substitute materials. In total, 57 tests in human specimens and 180 tests in the substitute materials were performed. RESULTS In human temporal bone, average pull-out forces ranged from 220 N to 285 N between screws. Joint stiffness in human temporal bone ranged between 14 N/mm and 358 N/mm. Statistically significant differences between the tested screws were measured in terms of stiffness and elastic energy. One screw type failed insertion due to tip breakage. No significant differences occurred between screws in maximum pull-out force. The average pull-out values of SFFE were 14.1 N higher compared to human specimen. CONCLUSION Orthodontic miniscrews provided rigid fixation when partially inserted in human temporal bone, as evidenced by pull-out forces and joint stiffness. Average values exceeded requirements despite variations between screws. Differences in stiffness and elastic energy indicate screw-specific interface mechanics. With proper insertion, orthodontic miniscrews appear suitable for microstereotactic frame anchoring during minimally invasive cochlear implant surgery. However, testing under more complex loading is needed to better predict clinical performance. For further pull-out tests, the most suitable substitute material is SFFE.
Collapse
Affiliation(s)
- Christian Menke
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | | | - Bastian Welke
- Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Hannover, Germany
| | - Thomas Lenarz
- Department of Otolaryngology and Cluster of Excellence, “Hearing4all,” Hannover Medical School, Hannover, Germany
| | - Omid Majdani
- Department of Otolaryngology, Medizincampus Wolfsburg der Universitätsmedizin Göttingen, Wolfsburg, Germany
| | - Thomas S. Rau
- Department of Otolaryngology and Cluster of Excellence, “Hearing4all,” Hannover Medical School, Hannover, Germany
| |
Collapse
|
6
|
Hijazi KM, Dixon SJ, Armstrong JE, Rizkalla AS. Titanium Alloy Implants with Lattice Structures for Mandibular Reconstruction. MATERIALS (BASEL, SWITZERLAND) 2023; 17:140. [PMID: 38203994 PMCID: PMC10779528 DOI: 10.3390/ma17010140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 11/30/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024]
Abstract
In recent years, the field of mandibular reconstruction has made great strides in terms of hardware innovations and their clinical applications. There has been considerable interest in using computer-aided design, finite element modelling, and additive manufacturing techniques to build patient-specific surgical implants. Moreover, lattice implants can mimic mandibular bone's mechanical and structural properties. This article reviews current approaches for mandibular reconstruction, their applications, and their drawbacks. Then, we discuss the potential of mandibular devices with lattice structures, their development and applications, and the challenges for their use in clinical settings.
Collapse
Affiliation(s)
- Khaled M. Hijazi
- School of Biomedical Engineering, Faculty of Engineering, The University of Western Ontario, London, ON N6A 3K7, Canada
- Bone and Joint Institute, The University of Western Ontario, London, ON N6G 2V4, Canada
| | - S. Jeffrey Dixon
- Bone and Joint Institute, The University of Western Ontario, London, ON N6G 2V4, Canada
- Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Jerrold E. Armstrong
- Division of Oral and Maxillofacial Surgery, Department of Otolaryngology Head and Neck Surgery, Henry Ford Hospital, Detroit, MI 48202, USA
| | - Amin S. Rizkalla
- School of Biomedical Engineering, Faculty of Engineering, The University of Western Ontario, London, ON N6A 3K7, Canada
- Bone and Joint Institute, The University of Western Ontario, London, ON N6G 2V4, Canada
- Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON N6A 5C1, Canada
- Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario, London, ON N6A 5B9, Canada
| |
Collapse
|
7
|
Krennmair S, Malek M, Stehrer R, Stähler P, Otto S, Postl L. The effect of frontal trauma on the edentulous mandible with four different interforaminal implant-prosthodontic anchoring configurations. A 3D finite element analysis. Eur J Med Res 2023; 28:608. [PMID: 38115128 PMCID: PMC10729383 DOI: 10.1186/s40001-023-01580-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023] Open
Abstract
PURPOSE The present three-dimensional (3D) finite element analysis (FEA) was aimed to assess the biomechanical effects and fracture risks of four different interforaminal implant-prosthodontic anchoring configurations exposed to frontal trauma. MATERIAL AND METHODS A symphyseal frontal trauma of 1 MPa was applied to four dental implant models with different configurations (two unsplinted interforaminal implants [2IF-U], two splinted interforaminal implants [2IF-S], four unsplinted interforaminal implants[ 4IF-U], four splinted interforaminal implants [4IF-S]. By using a 3D-FEA analysis the effective cortical bone stress values were evaluated in four defined regions of interest (ROI) (ROI 1: symphyseal area; ROI 2: preforaminal area; ROI 3: mental foraminal area; and ROI 4: condylar neck) followed by a subsequent intermodel comparison. RESULTS In all models the frontal traumatic force application revealed the highest stress values in the condylar neck region. In both models with a four-implant configuration (4IF-U, 4IF-S), the stress values in the median mandibular body (ROI 1) and in the condylar neck region (ROI 4) were significantly reduced (P <0.01) compared with the two-implant models (2IF-U, 2IF-S). However, in ROI 1, the model with four splinted implants (4IF-S) showed significantly (P < 0.01) reduced stress values compared to the unsplinted model (4IF-U). In addition, all models showed increased stress patterns in the area adjacent to the posterior implants, which is represented by increased stress values for both 2IF-U and 2IF-S in the preforaminal area (ROI 3) and for the four implant-based models (4IF-U, 4IF-S) in the mental foraminal area. CONCLUSION The configuration of four splinted interforaminal implants showed the most beneficial distribution of stress pattern representing reduced stress distribution and associated reduced fracture risk in anterior symphysis, condylar neck and preforaminal region.
Collapse
Affiliation(s)
- Stefan Krennmair
- Medical Faculty, Johannes Kepler University Linz, Altenberger Strasse 69, 4040, Linz, Austria
- Department of Oral and Maxillofacial Surgery, Kepler University Hospital, Johannes Kepler University, Krankenhausstrasse 7a, Linz, Austria
- NumBioLab, Ludwig-Maximilians University of Munich, Munich, Germany
| | - Michael Malek
- Department of Oral and Maxillofacial Surgery, Kepler University Hospital, Johannes Kepler University, Krankenhausstrasse 7a, Linz, Austria
| | - Raphael Stehrer
- Department of Oral and Maxillofacial Surgery, Kepler University Hospital, Johannes Kepler University, Krankenhausstrasse 7a, Linz, Austria
| | - Philip Stähler
- Department of Oral and Maxillofacial Surgery, Ludwig-Maximilians-University Munich, Lindwurmstrasse 2a, 80337, Munich, Germany
| | - Sven Otto
- Department of Oral and Maxillofacial Surgery, Ludwig-Maximilians-University Munich, Lindwurmstrasse 2a, 80337, Munich, Germany
| | - Lukas Postl
- Medical Faculty, Johannes Kepler University Linz, Altenberger Strasse 69, 4040, Linz, Austria.
- Department of Oral and Maxillofacial Surgery, Kepler University Hospital, Johannes Kepler University, Krankenhausstrasse 7a, Linz, Austria.
- Department of Oral and Maxillofacial Surgery, Ludwig-Maximilians-University Munich, Lindwurmstrasse 2a, 80337, Munich, Germany.
| |
Collapse
|
8
|
Dario V, Michelangelo-Santo G, Roberto B, Fabio F. Is All-on-four effective in case of partial mandibular resection? A 3D finite element study. JOURNAL OF STOMATOLOGY, ORAL AND MAXILLOFACIAL SURGERY 2023; 124:101463. [PMID: 37028491 DOI: 10.1016/j.jormas.2023.101463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 03/26/2023] [Accepted: 04/01/2023] [Indexed: 04/09/2023]
Abstract
INTRODUCTION The aim of the work is to analyze stress distribution on 3D Finite Element (FE) models at bone, implant, and framework level of different designs for fixed implant-supported prostheses in completely edentulous patients, comparing results on whole and partially resected mandibles. MATERIALS AND METHODS 3D anisotropic FE models of a whole and of a partially resected mandible were created using a TC scan of a cadaver's totally edentulous mandible. Two types of totally implant-supported rehabilitation were simulated, with four implants: parallel fixtures on whole mandible and on resected mandible, All-on-four-configured fixtures on whole mandible and on partially resected mandible. A superstructure comprising only metal components of a prosthetic framework were added, while stress distribution and its maximum values were analyzed at bone, implant, and superstructure level. RESULTS The results highlight that: (1) implant stresses are greater on the whole mandible than on the resected one; (2) framework and cancellous-bone stresses are comparable in all cases; (3) on the resected mandible, maximum stress levels at the cortical-bone/implant interface are higher than in whole-mandible rehabilitation. The opposite applies for maximum stresses on external cortical bone, measured radially with respect to the implant from the point of maximum stress at the interface. DISCUSSION On the resected mandible, All-on-four configuration proved biomechanically superior to parallel implants considering radial stresses on implants and cortical bone. Still, maximum stresses increase at the bone/implant interface. A design with four parallel implants minimizes the stress on a resected mandible while, on the whole mandible, the All-on-four rehabilitation proves superior at all levels (bone, implant, and framework).
Collapse
Affiliation(s)
- Vangi Dario
- Department of Industrial Engineering, Università degli Studi di Firenze, Via di Santa Marta 3, Firenze (FI) 50139, Italy
| | - Gulino Michelangelo-Santo
- Department of Industrial Engineering, Università degli Studi di Firenze, Via di Santa Marta 3, Firenze (FI) 50139, Italy.
| | - Branchi Roberto
- Department of Prosthodontics, Clinica Odontoiatrica Universitaria Ponte di Mezzo, Via del Ponte di Mezzo 46/48, Firenze (FI) 50127, Italy
| | - Ferretti Fabio
- Department of Prosthodontics, Clinica Odontoiatrica Universitaria Ponte di Mezzo, Via del Ponte di Mezzo 46/48, Firenze (FI) 50127, Italy
| |
Collapse
|
9
|
Teimoori M, Nokhbatolfoghahaei H, Khojasteh A. Bilayer scaffolds/membranes for bone tissue engineering applications: A systematic review. BIOMATERIALS ADVANCES 2023; 153:213528. [PMID: 37352742 DOI: 10.1016/j.bioadv.2023.213528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/25/2023]
Abstract
OBJECTIVE This systematic review evaluates the purpose, materials, physio-mechanical, and biological effects of bilayer scaffolds/membranes used for bone tissue engineering applications. METHODS A comprehensive electronic search of English-language literature from 2012 to October 2022 was conducted in PubMed, Scopus, ScienceDirect, and Google Scholar online databases according to the PRISMA 2020 guidelines. The quality of animal studies was evaluated through the SYRCLE's risk of bias tool. RESULTS A total of 77 studies were sought for retrieval, and 39 studies met the inclusion criteria. According to the synthesis results, most bilayers had a dense barrier layer that prevented connective tissue penetration and a loose osteogenic layer that supported cell migration and osteogenesis. PLGA, PCL, and chitosan were the most common polymers in the barrier layers, while the most utilized polymers in osteogenic layers were PLGA and gelatin. Electrospinning and solvent casting were the most common fabrication methods to design the bilayer structures. Many studies reported higher biological results for bilayers compared to their single layers. Also, fabricated bilayers' in vitro osteogenesis and in vivo new bone formation were significantly superior or at least comparable to the frequently used commercial membranes. CONCLUSION 1) Bilayers with two distinct layers and different materials, porosities, mechanical properties, and biological behavior can significantly improve heterogeneous bone regeneration; 2) the addition of ceramics and/or drugs to the osteogenic layer enhances the osteogenic properties of the bilayers; 3) fabrication method and pore size of the layers play an important role in determining the mechanical and biological behavior of them.
Collapse
Affiliation(s)
- Mahdis Teimoori
- Student Research Committee, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hanieh Nokhbatolfoghahaei
- Dental Research Center, Research Institute of Dental Sciences, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Arash Khojasteh
- Dental Research Center, Research Institute of Dental Sciences, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Cranio-Maxillofacial Surgery, University Hospital, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
| |
Collapse
|
10
|
Braga C, Pozzan L, Ciotola C, Viganoni C, Torelli L, Contardo L. Bone quality in relation to skeletal maturation in palatal miniscrews insertion sites. Am J Orthod Dentofacial Orthop 2023; 164:406-415. [PMID: 37012108 DOI: 10.1016/j.ajodo.2023.02.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 02/01/2023] [Accepted: 02/01/2023] [Indexed: 04/03/2023]
Abstract
INTRODUCTION This study aimed to investigate the relationship between bone density and quantity at the insertion sites of palatal miniscrews and skeletal maturation-evaluated with the middle phalanx maturation method-in growing patients. METHODS Sixty patients were analyzed as having a staged third finger middle phalanx radiograph and a cone-beam computed tomography of the maxilla. On the cone-beam computed tomography, a grid was designed to parallel the midpalatal suture (MPS) and posterior to the nasopalatine foramen, both on the palatal and lower nasal cortical bones. Bone density and thickness were measured at the intersections, and medullary bone density was also calculated. RESULTS Of patients in MPS stages 1-3, 67.6% showed a mean palatal cortical thickness of <1 mm, whereas in 78.3% of the patients in stages 4 and 5, it was >1 mm. The nasal cortical thickness showed a similar trend (MPS stages 1-3: 62.16% <1 mm; MPS stages 4 and 5: 65.2% >1 mm). There was a significant difference in the density of the palatal cortical bone between MPS stages 1-3 (1272.05 ± 191.13) and stages 4 and 5 (1572.33 ± 274.89) and in nasal cortical density between MPS stages 1-3 (1428.09 ± 198.97) and stages 4 and 5 (1597.97 ± 267.75) (P <0.001). CONCLUSIONS This study revealed a correlation between skeletal maturity and maxillary bone quality. MPS stages 1-3 have lower palatal cortical bone density and thickness but high nasal cortical bone density values. MPS stage 4 and, even more, stage 5 show increasing palatal cortical bone thickness and palatal and nasal cortical bone density values.
Collapse
Affiliation(s)
- Camilla Braga
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Lucia Pozzan
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy.
| | - Carlo Ciotola
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Chiara Viganoni
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Lucio Torelli
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| | - Luca Contardo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy
| |
Collapse
|
11
|
Su Q, Qiao Y, Xiao Y, Yang S, Wu H, Li J, He X, Hu X, Yang H, Yong X. Research progress of 3D printed poly (ether ether ketone) in the reconstruction of craniomaxillofacial bone defects. Front Bioeng Biotechnol 2023; 11:1259696. [PMID: 37662437 PMCID: PMC10469012 DOI: 10.3389/fbioe.2023.1259696] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Accepted: 08/07/2023] [Indexed: 09/05/2023] Open
Abstract
The clinical challenge of bone defects in the craniomaxillofacial region, which can lead to significant physiological dysfunction and psychological distress, persists due to the complex and unique anatomy of craniomaxillofacial bones. These critical-sized defects require the use of bone grafts or substitutes for effective reconstruction. However, current biomaterials and methods have specific limitations in meeting the clinical demands for structural reinforcement, mechanical support, exceptional biological performance, and aesthetically pleasing reconstruction of the facial structure. These drawbacks have led to a growing need for novel materials and technologies. The growing development of 3D printing can offer significant advantages to address these issues, as demonstrated by the fabrication of patient-specific bioactive constructs with controlled structural design for complex bone defects in medical applications using this technology. Poly (ether ether ketone) (PEEK), among a number of materials used, is gaining recognition as a feasible substitute for a customized structure that closely resembles natural bone. It has proven to be an excellent, conformable, and 3D-printable material with the potential to replace traditional autografts and titanium implants. However, its biological inertness poses certain limitations. Therefore, this review summarizes the distinctive features of craniomaxillofacial bones and current methods for bone reconstruction, and then focuses on the increasingly applied 3D printed PEEK constructs in this field and an update on the advanced modifications for improved mechanical properties, biological performance, and antibacterial capacity. Exploring the potential of 3D printed PEEK is expected to lead to more cost-effective, biocompatible, and personalized treatment of craniomaxillofacial bone defects in clinical applications.
Collapse
Affiliation(s)
- Qiao Su
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu, Sichuan, China
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
- West China School of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yixin Qiao
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yile Xiao
- Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | - Shuhao Yang
- Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, Sichuan, China
| | - Haoming Wu
- Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, Sichuan, China
| | - Jianan Li
- State Key Laboratory of Biotherapy, State Key Laboratory and Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xinlong He
- State Key Laboratory of Biotherapy, State Key Laboratory and Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xulin Hu
- Clinical Medical College and Affiliated Hospital of Chengdu University, Chengdu, Sichuan, China
- State Key Laboratory of Biotherapy, State Key Laboratory and Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Hui Yang
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Xin Yong
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu, Sichuan, China
| |
Collapse
|
12
|
Huo J, Hirsch JM, Gamstedt EK. Analytical Study of Stress Distributions around Screws in Flat Mandibular Bone under In-Plane Loading. Bioengineering (Basel) 2023; 10:786. [PMID: 37508813 PMCID: PMC10376365 DOI: 10.3390/bioengineering10070786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/21/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
A known complication for mechanically loaded bone implants is the instability due to screw loosening, resulting in infection and the non-union of fractures. To investigate and eventually prevent such bone degradation, it is useful to know the stress state in the bone around the screw. Considering only in-plane loadings and simplifying the mandibular bone into an orthotropic laminated plate, the analysis was reduced to a two-dimensional pin-loaded plate problem. An analytic model, based on the complex stress analysis, was introduced to the bone biomechanics field to obtain the stress distributions around the screw hole in the bone. The dimensionless normalized stresses were found to be relatively insensitive to the locations of the screw hole over the mandible. Parametric analyses were carried out regarding the friction coefficient and load direction. It was found that the load direction had a negligible influence. On the contrary, the friction coefficient had a significant effect on the stress distributions. Whether the screw was well bonded or not thus played an important role. The proposed analytic model could potentially be used to study bone failure together with stress-based failure criteria.
Collapse
Affiliation(s)
- Jinxing Huo
- Division of Applied Mechanics, Department of Materials Science and Engineering, Uppsala Univeristy, Box 35, SE-751 03 Uppsala, Sweden
| | - Jan-Michaél Hirsch
- Department of Surgical Sciences, Oral & Maxillofacial Surgery, Uppsala University, SE-751 85 Uppsala, Sweden
| | - E Kristofer Gamstedt
- Division of Applied Mechanics, Department of Materials Science and Engineering, Uppsala Univeristy, Box 35, SE-751 03 Uppsala, Sweden
| |
Collapse
|
13
|
Ueda N, Zaizen M, Imai Y, Kirita T. Measurement of Thickness at the Inferior Border of the Mandible Using Computed Tomography Images: A Retrospective Study including 300 Japanese Cases. Tomography 2023; 9:1236-1245. [PMID: 37489466 PMCID: PMC10366919 DOI: 10.3390/tomography9040098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/17/2023] [Accepted: 06/21/2023] [Indexed: 07/26/2023] Open
Abstract
Vascularised fibular free flaps are integral to reconstructive surgery for head and neck tumours. We investigated the morphological characteristics of the mandible to improve the incidence of plate-related complications after surgery. Using standard radiological software, thickness measurements of the inferior or posterior margin of the mandible were obtained from computed tomography images of 300 patients at seven sites: (1) mandibular symphysis, (2) midpoint between the mandibular symphysis and mental foramen, (3) mental foramen, (4) midpoint between the mental foramen and antegonial notch, (5) antegonial notch, (6) mandibular angular apex (gonion), and (7) neck lateral border of the dentate cartilage. Relationships between age, sex, height, weight, the number of remaining teeth in the mandible, and the thickness of each mandible were also investigated. Measurement point 1 had the largest median mandibular thickness (11.2 mm), and measurement point 6 had the smallest (5.4 mm). Females had thinner measurements than males at all points, with significant differences at points 1, 2, 3, 4, and 7 (p < 0.001). Age and number of remaining teeth in the mandible did not correlate with mandibular thickness; however, height and weight correlated at all points except point 6. Thickness measurements obtained at the sites provide a practical reference for mandibular reconstruction. Choosing the fixation method based on the measured thickness of the mandible at each site allows for sound plating.
Collapse
Affiliation(s)
- Nobuhiro Ueda
- Department of Oral and Maxillofacial Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan
| | - Miki Zaizen
- Department of Oral and Maxillofacial Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan
| | - Yuichiro Imai
- Department of Oral and Maxillofacial Surgery, Rakuwakai Otowa Hospital, 2 Chinji-cho, Yamashima-ku, Kyoto 607-8062, Japan
| | - Tadaaki Kirita
- Department of Oral and Maxillofacial Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan
| |
Collapse
|
14
|
Sun X, Cheng K, Liu Y, Ke S, Zhang W, Wang L, Yang F. Biomechanical comparison of all-on-4 and all-on-5 implant-supported prostheses with alteration of anterior-posterior spread: a three-dimensional finite element analysis. Front Bioeng Biotechnol 2023; 11:1187504. [PMID: 37397958 PMCID: PMC10313229 DOI: 10.3389/fbioe.2023.1187504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 06/08/2023] [Indexed: 07/04/2023] Open
Abstract
Introduction: The all-on-4 concept is widely used in clinical practice. However, the biomechanical changes following the alteration of anterior-posterior (AP) spread in all-on-4 implant-supported prostheses have not been extensively studied. Methods: Three-dimensional finite element analysis was used to compare the biomechanical behavior of all-on-4 and all-on-5 implant-supported prostheses with a change in anterior-posterior (AP) spread. A three-dimensional finite element analysis was performed on a geometrical mandible model containing 4 or 5 implants. Four different implant configurations were modeled by varying the angle of inclination of the distal implants (0°and 30°), including all-on-4a, all-on-4b, all-on-5a, and all-on-5b, and a 100 N force was successively applied to the anterior and unilateral posterior teeth to observe and analyze the differences in the biomechanical behavior of each model under the static influence at different position. Results: Adding an anterior implant to the dental arch according to the all-on-4 concept with a distal 30° tilt angle implant exhibited the best biomechanical behavior. However, when the distal implant was implanted axially, there was no significant difference between the all-on-4 and all-on-5 groups. Discussion: In the all-on-5 group, increasing the AP spread with tilted terminal implants showed better biomechanical behavior. It can be concluded that placing an additional implant in the midline of the atrophic edentulous mandible and increasing the AP spread might be beneficial in improving the biomechanical behavior of tilted distal implants.
Collapse
Affiliation(s)
- Xin Sun
- Department of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Kangjie Cheng
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
- Key Laboratory of Special Purpose Equipment and Advanced Processing Technology, Ministry of Education and Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
- National International Joint Research Center of Special Purpose Equipment and Advanced Processing Technology, Zhejiang University of Technology, Hangzhou, China
| | - Yunfeng Liu
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
- Key Laboratory of Special Purpose Equipment and Advanced Processing Technology, Ministry of Education and Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
- National International Joint Research Center of Special Purpose Equipment and Advanced Processing Technology, Zhejiang University of Technology, Hangzhou, China
| | - Sipeng Ke
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Wentao Zhang
- Center for Plastic and Reconstructive Surgery, Department of Stomatology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Linhong Wang
- Center for Plastic and Reconstructive Surgery, Department of Stomatology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Fan Yang
- Department of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- Center for Plastic and Reconstructive Surgery, Department of Stomatology, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| |
Collapse
|
15
|
Decaup PH, Couture C, Garot E. Is the distribution of cortical bone in the mandibular corpus and symphysis linked to loading environment in modern humans? A systematic review. Arch Oral Biol 2023; 152:105718. [PMID: 37182318 DOI: 10.1016/j.archoralbio.2023.105718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 04/25/2023] [Accepted: 05/06/2023] [Indexed: 05/16/2023]
Abstract
OBJECTIVE The human mandible is a unique bone with specific external and internal morphological characteristics, influenced by a complex and challenging loading environment. Mandibular cortical thickness distribution in cross-sections is reported to be related to facial divergence patterns, cultural and dietary habits and more generally, specific loading environment. This review hypothesises that a process of environmental mechanical sensitivity is involved in the distribution of cortical bone in the mandibular corpus and symphysis in modern humans, and that loading regimes can influence this distribution pattern. Based on a review of the recent literature, this study aims to answer the following question: "Is the distribution of cortical bone in the mandibular corpus and symphysis linked to the loading environment in modern humans?" DESIGN A systematic review was undertaken using the PubMed/Medline, Scopus and Cochrane Library databases for publications from 1984 to 2022 investigating the relationship between cortical bone distribution in the mandibular corpus and the loading environment. A subgroup meta-analysis was performed to determine the overall effect of facial divergence on cortical thickness. RESULTS From a total of 2791 studies, 20 fulfilled the inclusion criteria. The meta-analyses were performed in eight studies using a randomised model, finding a significant overall effect of facial divergence on cortical thickness in posterior areas of the mandible (p < 0.01). CONCLUSIONS Within the limitations of this review, specific loading regimes and their consequent variables (diet, culture, facial divergence) were linked to cortical thickness distribution. Sex was found to be unrelated to cortical thickness pattern.
Collapse
Affiliation(s)
- Pierre-Hadrien Decaup
- Université de Bordeaux, PACEA, UMR 5199, Pessac, France; Université de Bordeaux, UFR des Sciences Odontologiques, Bordeaux, France.
| | | | - Elsa Garot
- Université de Bordeaux, PACEA, UMR 5199, Pessac, France; Université de Bordeaux, UFR des Sciences Odontologiques, Bordeaux, France
| |
Collapse
|
16
|
Kurakar M, Joshi U. Comparative Study of Miniplate vs Reconstruction Plate in the Management of Bilateral Parasymphysis Mandible Fracture: FEM Analysis. J Maxillofac Oral Surg 2023; 22:9-17. [PMID: 36703660 PMCID: PMC9871087 DOI: 10.1007/s12663-021-01649-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/23/2021] [Indexed: 01/29/2023] Open
Abstract
Aim and Objective The present study compared the stability of fracture fragments in the management of bilateral parasymphysis mandible fracture with Miniplate fixation and Reconstruction plate fixation using finite element analysis. Material and Method 3D FE Mandible model was created using CT scanner. Two bilateral parasymphysis mandible fracture models were created. Model 1 was fixed with Miniplates, and Model 2 was fixed with Reconstruction plate. Loading forces of 120 N at molar region and 62.5 N at incisor region were applied. These two models were imported to ANSY'S Workbench Software. Result Miniplate fixation model showed comparatively reduced gap between fragments than Reconstruction plate. But the gap values of both the models were within the physiologic limit of healing under this specific loading. Analytically Miniplates were superior to Reconstruction plate in the management of bilateral parasymphysis fracture. Conclusion Analytically Miniplates are superior to Reconstruction plate in the management of bilateral parasymphysis fracture. As the masticatory forces were reduced during fracture healing period, both fixations provide satisfactory healing. So both Miniplate and Reconstruction plate can be considered as fixation method for bilateral parasymphysis mandible fracture.
Collapse
Affiliation(s)
- Manju Kurakar
- Department of Oral and Maxillofacial Surgery, Sinhgad Dental College and Hospital, Pune, India
- Affiliated to Maharashtra University of Health Science, Nashik, Maharshtra India
| | - Udupikrishna Joshi
- Department of Oral and Maxillofacial Surgery, HKE Society’s SNijalingappa Institute of Dental Science and Research, Gulbarga, India
- Affiliated to Rajiv Gandhi University of Health Sciences, Bangalore, Karnataka India
| |
Collapse
|
17
|
Li Y, Li H, Lai Q, Xue R, Zhu K, Deng Y. Finite element analysis of 3D-printed personalized titanium plates for mandibular angle fracture. Comput Methods Biomech Biomed Engin 2023; 26:78-89. [PMID: 35587215 DOI: 10.1080/10255842.2022.2047952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This paper discussed the size of 3 D-printed personalized titanium plates that can gain maximum stability of mandibular fracture and minimize stress shielding through finite element analysis. A 3 D virtual model of mandible with mandibular angle fracture was created from the CT data of patient. 3 D-printed personalized titanium plates varying in length and thickness were designed, and finite element analysis was performed under different loading conditions and fracture healing periods. After that, the stress distribution and deformation of the mandible with gonial fracture could be observed, and the stress shielding rate could be obtained. Finally, SPSS21.0 was used for statistical analysis. The results of finite element analysis indicated that as the thickness of titanium plates and the healing time decreased, the maximum displacement increased, under a certain condition in which the pore size, the width, the hole distance and the bridge spacing were 2.0 mm, 4.0 mm, 6.0 mm, 12.0 mm, respectively. What's more, in this condition, the thicker the titanium plate and the shorter the healing time were, the higher the stress shielding was at central occlusion. When the thickness of the personalized 3 D-printed titanium plate was 1.0 mm, the maximum displacement tended to be stable and the stress shielding was minimized. It can not only improve the bone stability after tension band fixation, but also minimize the stress shielding, which is expected to expand the indications of tension band fixation.
Collapse
Affiliation(s)
- Yan Li
- The Second Hospital of Shandong University, Jinan, People's Republic of China.,Department of Dermatology, Jinan Central Hospital, Shandong University, Jinan, Shandong Province, People's Republic of China
| | - Hui Li
- The Second Hospital of Shandong University, Jinan, People's Republic of China
| | - Qingguo Lai
- Department of Oral and Maxillofacial Surgery, The Second Hospital of Shandong University, Jinan, Shandong Province, People's Republic of China.,Research Center of 3D Printing in Stomatology of Shandong University, Shandong University, Shandong Province, People's Republic of China
| | - Runqi Xue
- Department of Oral and Maxillofacial Surgery, The Second Hospital of Shandong University, Jinan, Shandong Province, People's Republic of China
| | - Kaiwen Zhu
- Department of Oral and Maxillofacial Surgery, The Second Hospital of Shandong University, Jinan, Shandong Province, People's Republic of China
| | - Yanwei Deng
- Department of Oral and Maxillofacial Surgery, The Second Hospital of Shandong University, Jinan, Shandong Province, People's Republic of China
| |
Collapse
|
18
|
Smith AL, Davis J, Panagiotopoulou O, Taylor AB, Robinson C, Ward CV, Kimbel WH, Alemseged Z, Ross CF. Does the model reflect the system? When two-dimensional biomechanics is not 'good enough'. J R Soc Interface 2023; 20:20220536. [PMID: 36695017 PMCID: PMC9874278 DOI: 10.1098/rsif.2022.0536] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Models are mathematical representations of systems, processes or phenomena. In biomechanics, finite-element modelling (FEM) can be a powerful tool, allowing biologists to test form-function relationships in silico, replacing or extending results of in vivo experimentation. Although modelling simplifications and assumptions are necessary, as a minimum modelling requirement the results of the simplified model must reflect the biomechanics of the modelled system. In cases where the three-dimensional mechanics of a structure are important determinants of its performance, simplified two-dimensional modelling approaches are likely to produce inaccurate results. The vertebrate mandible is one among many three-dimensional anatomical structures routinely modelled using two-dimensional FE analysis. We thus compare the stress regimes of our published three-dimensional model of the chimpanzee mandible with a published two-dimensional model of the chimpanzee mandible and identify several fundamental differences. We then present a series of two-dimensional and three-dimensional FE modelling experiments that demonstrate how three key modelling parameters, (i) dimensionality, (ii) symmetric geometry, and (iii) constraints, affect deformation and strain regimes of the models. Our results confirm that, in the case of the primate mandible (at least), two-dimensional FEM fails to meet this minimum modelling requirement and should not be used to draw functional, ecological or evolutionary conclusions.
Collapse
Affiliation(s)
- Amanda L. Smith
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th St, Chicago, IL 60637, USA,Department of Anatomy, Pacific Northwest University of Health Sciences, Yakima, WA 90981, USA
| | - Julian Davis
- Department of Engineering, University of Southern Indiana, 8600 University Blvd, Evansville, IN 47712, USA
| | - Olga Panagiotopoulou
- Department of Anatomy & Developmental Biology, Monash Biomedicine Discovery Institute, Faculty of Medicine Nursing and Health Sciences, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | | | - Chris Robinson
- Department of Biological Sciences, Bronx Community College, Bronx, NY 10453, USA,Doctoral Program in Anthropology, The Graduate Center, City University of New York, New York, NY 10016, USA
| | - Carol V. Ward
- Department of Pathology & Anatomical Sciences, One Hospital Drive, University of Missouri, Columbia, MO 65212, USA
| | - William H. Kimbel
- School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85287-4101, USA
| | - Zeresenay Alemseged
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th St, Chicago, IL 60637, USA
| | - Callum F. Ross
- Department of Anatomy, Pacific Northwest University of Health Sciences, Yakima, WA 90981, USA
| |
Collapse
|
19
|
Luo X, Rong Q, Luan Q, Yu X. Effect of partial restorative treatment on stress distributions in non-carious cervical lesions: a three-dimensional finite element analysis. BMC Oral Health 2022; 22:607. [PMID: 36522633 PMCID: PMC9753429 DOI: 10.1186/s12903-022-02647-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/05/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Partial restoration combined with periodontal root coverage surgery can be applied to the treatment of non-carious cervical lesions (NCCLs) accompanied with gingival recessions in clinical practice. However, the feasibility of NCCL partial restorative treatment from a biomechanical perspective remains unclear. This study aimed to investigate the effect of partial restorations on stress distributions in the NCCLs of mandibular first premolars via three-dimensional finite element analysis. METHODS Three-dimensional finite element models of buccal wedge-shaped NCCLs in various locations of a defected zenith (0 mm, 1 mm, and 2 mm) were constructed and divided into three groups (A, B, and C). Three partially restored NCCL models with different locations of the lower restoration border (1 mm, 1.5 mm, and 2 mm), and one completely restored NCCL model were further constructed for each group. The following restorative materials were used in all restoration models: composite resin (CR), glass-ionomer cement (GIC), and mineral trioxide aggregate (MTA). The first principal stress distributions under buccal oblique loads of 100 N were analyzed. Restoration bond failures were also evaluated based on stress distributions at dentin-restoration interfaces. RESULTS When the partial restoration fully covered the defected zenith, the first principal stress around the zenith decreased and the maximum tensile stress was concentrated at the lower restoration border. When the partial restoration did not cover the defected zenith, the first principal stress distribution patterns were similar to those in unrestored models, with the maximum tensile stress remaining concentrated at the zenith. As the elastic modulus of the restorative material was altered, the stress distributions at the interface were not obviously changed. Restoration bond failures were not observed in CR, but occurred in GIC and MTA in most models. CONCLUSIONS Partial restorations that fully covered defected zeniths improved the stress distributions in NCCLs, while the stress distributions were unchanged or worsened under other circumstances. CR was the optimal material for partial restorations compared to GIC and MTA.
Collapse
Affiliation(s)
- Xin Luo
- grid.11135.370000 0001 2256 9319Department of Periodontology, Peking University School and Hospital of Stomatology, No. 22, Zhongguancun South Avenue, Haidian District, Beijing, 100081 China
| | - Qiguo Rong
- grid.11135.370000 0001 2256 9319Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, China
| | - Qingxian Luan
- grid.11135.370000 0001 2256 9319Department of Periodontology, Peking University School and Hospital of Stomatology, No. 22, Zhongguancun South Avenue, Haidian District, Beijing, 100081 China
| | - Xiaoqian Yu
- grid.11135.370000 0001 2256 9319Department of Periodontology, Peking University School and Hospital of Stomatology, No. 22, Zhongguancun South Avenue, Haidian District, Beijing, 100081 China
| |
Collapse
|
20
|
Wang PF, Wang YT. Development of the Customized Asymmetric Fixation Plate to Resist Postoperative Relapse of Hemifacial Microsomia Following BSSO: Topology Optimization and Biomechanical Testing. Ann Biomed Eng 2022; 51:987-1001. [PMID: 36463368 DOI: 10.1007/s10439-022-03111-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 11/16/2022] [Indexed: 12/04/2022]
Abstract
Hemifacial microsomia (HFM), one of the most common congenital facial anomalies, was usually treated with the bilateral sagittal split osteotomy (BSSO) procedure to correct the asymmetric appearance and malocclusion of the mandible. However, the frequent post-operative relapse incidents would lead to the restoration of the mandibular segment to its preoperative position and failure of the BSSO procedure. In this study, a customized asymmetric fixed plate (CAF plate) was developed to resist relapse due to hemifacial microsomia occlusal forces and the different muscular traction forces on both sides of the mandible. For the actual HFM case in this study, the reconstructed mandibular segmental bone model was fixed using BSSO with a rectangular plate (the original CAF plate appearance) in the topology optimization analysis. With the topology optimization technique, the CAF plate was designed with a lightweight profile and excellent structural strength in consideration of the HFM asymmetrical muscle traction and occlusal force. Using biomechanical simulations, the von-Mises stress and CAF plate mandibular segment displacement and the miniplate were compared to evaluate which had superior relapse resistance. In the in-vitro biomechanical test, a fatigue force of 250,000 cycles and a constant muscle traction force were applied to the HFM mandibular model, which was fixed with the CAF plate fabricated using metal 3D printing (selective laser melting, SLM) to obtain the mandibular segment displacement as a relapse assessment. The topology optimization analysis showed that the CAF plate has the best characteristics, light weight and structural strength with 30% volume retention. The biomechanical analysis showed that the maximum von Mises stress of the mini-plate was 2.71 times higher than that of the CAF plate. The relapse displacement of the mandibular segment fixed with the mini-plate was 1.62 times higher than that fixed with the CAF plate. The CAF plate ability to resist relapse was confirmed by the biomechanical testing results so that only 0.29 mm of recurrence displacement was observed in the mandibular segment. The results indicated that the CAF plate structural strength and resistance to relapse was significantly better than that of the mini-plate. This study developed a customized asymmetric fixation plate for hemifacial microsomia, integrating topology optimization, metal 3D printing, and in vitro biomechanical testing to resist occlusal forces and differential muscle traction on both sides of the mandible to reduce relapse and improve fixation stability.
Collapse
Affiliation(s)
- Po-Fang Wang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
- Craniofacial Center, Department of Plastic and Reconstruction Surgery, Chang Gung Memorial Hospital, 5, Fu-Hsing Street, Kueishan, Taoyuan, 333, Taiwan
| | - Yu-Tzu Wang
- Department of Mechanical and Electro-Mechanical Engineering, TamKang University, No.151, Yingzhuan Rd., Tamsui Dist., New Taipei City, 251301, Taiwan.
| |
Collapse
|
21
|
Ruf P, Orassi V, Fischer H, Steffen C, Duda GN, Heiland M, Kreutzer K, Checa S, Rendenbach C. Towards mechanobiologically optimized mandible reconstruction: CAD/CAM miniplates vs. reconstruction plates for fibula free flap fixation: A finite element study. Front Bioeng Biotechnol 2022; 10:1005022. [PMID: 36466355 PMCID: PMC9712730 DOI: 10.3389/fbioe.2022.1005022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/13/2022] [Indexed: 07/28/2023] Open
Abstract
Due to their advantages in applicability, patient-specific (CAD/CAM) reconstruction plates are increasingly used in fibula free flap mandible reconstruction. In addition, recently, CAD/CAM miniplates, with further advantages in postoperative management, have been introduced. However, biomechanical conditions induced by CAD/CAM systems remain partially unknown. This study aimed to evaluate the primary fixation stability of CAD/CAM fixators. For a patient-specific scenario, the biomechanical conditions induced in a one segmental fibula free flap stabilized using either a CAD/CAM reconstruction plate or CAD/CAM miniplates were determined using finite element analysis. The main output parameters were the strains between intersegmental bone surfaces and stresses in the fixation systems due to different biting scenarios. CAD/CAM miniplates resulted in higher mechanical strains in the mesial interosseous gap, whereas CAD/CAM reconstruction plate fixation resulted in higher strains in the distal interosseous gap. For all investigated fixation systems, stresses in the fixation systems were below the material yield stress and thus material failure would not be expected. While the use of CAD/CAM miniplates resulted in strain values considered adequate to promote bone healing in the mesial interosseous gap, in the distal interosseous gap CAD/CAM reconstruction plate fixation might result in more beneficial tissue straining. A mechanical failure of the fixation systems would not be expected.
Collapse
Affiliation(s)
- Philipp Ruf
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Vincenzo Orassi
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Heilwig Fischer
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Claudius Steffen
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Georg N. Duda
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Max Heiland
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Kilian Kreutzer
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sara Checa
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Carsten Rendenbach
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| |
Collapse
|
22
|
Dorado S, Arias A, Jimenez-Octavio JR. Biomechanical Modelling for Tooth Survival Studies: Mechanical Properties, Loads and Boundary Conditions-A Narrative Review. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7852. [PMID: 36363451 PMCID: PMC9657341 DOI: 10.3390/ma15217852] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 06/16/2023]
Abstract
Recent biomechanical studies have focused on studying the response of teeth before and after different treatments under functional and parafunctional loads. These studies often involve experimental and/or finite element analysis (FEA). Current loading and boundary conditions may not entirely represent the real condition of the tooth in clinical situations. The importance of homogenizing both sample characterization and boundary conditions definition for future dental biomechanical studies is highlighted. The mechanical properties of dental structural tissues are presented, along with the effect of functional and parafunctional loads and other environmental and biological parameters that may influence tooth survival. A range of values for Young's modulus, Poisson ratio, compressive strength, threshold stress intensity factor and fracture toughness are provided for enamel and dentin; as well as Young's modulus and Poisson ratio for the PDL, trabecular and cortical bone. Angles, loading magnitude and frequency are provided for functional and parafunctional loads. The environmental and physiological conditions (age, gender, tooth, humidity, etc.), that may influence tooth survival are also discussed. Oversimplifications of biomechanical models could end up in results that divert from the natural behavior of teeth. Experimental validation models with close-to-reality boundary conditions should be developed to compare the validity of simplified models.
Collapse
Affiliation(s)
- Saúl Dorado
- Department of Mechanical Engineering, Escuela Técnica Superior de Ingeniería ICAI, Universidad Pontificia Comillas, 28015 Madrid, Spain
| | - Ana Arias
- Department of Conservative and Prosthetic Dentistry, School of Dentistry, Complutense University, 28040 Madrid, Spain
| | - Jesus R. Jimenez-Octavio
- Instituto de Investigación Tecnológica, Escuela Técnica Superior de Ingeniería ICAI, Universidad Pontificia Comillas, 28015 Madrid, Spain
| |
Collapse
|
23
|
van Leeuwen T, Schneider MTY, van Lenthe GH, Vereecke EE. The effect of different grasping types on strain distributions in the trapezium of bonobos (Pan paniscus). J Biomech 2022; 144:111284. [PMID: 36174384 DOI: 10.1016/j.jbiomech.2022.111284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/25/2022] [Accepted: 08/31/2022] [Indexed: 11/29/2022]
Abstract
The thumb has played a key role in primate evolution due to its involvement in grasping and manipulation. A large component of this wide functionality is by virtue of the uniquely shaped trapeziometacarpal (TMC) joint. This TMC joint allows for a broad range of functional positions, but how its bone structure is adapted to withstand such a large variety of loading regimes is poorly understood. Here, we outline a novel, integrated finite element - micro finite element (FE-µFE) workflow to analyse strain distributions across the internal bony architecture. We have applied this modelling approach to study functional adaptation in the bonobo thumb. More specifically, the approach allows us to evaluate how strain is distributed through the trapezium upon loading of its distal articular facet. As loading conditions, we use pressure distributions for different types of grasping that were estimated in a previous study. Model evaluation shows that the simulated strain values fall within realistic boundaries of the mechanical response of bone. The results show that the strain distributions between the simulated grasps are highly similar, with dissipation towards the proximo-ulnar cluster of trabeculae regardless of trapezial bone architecture. This study presents an innovative FE-µFE approach to simulating strain distributions, and yields insight in the functional adaptation of the TMC joint in bonobos.
Collapse
Affiliation(s)
- Timo van Leeuwen
- Department of Development and Regeneration, KU Leuven Campus Kulak, Kortrijk, Belgium; Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
| | - Marco T Y Schneider
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | | | - Evie E Vereecke
- Department of Development and Regeneration, KU Leuven Campus Kulak, Kortrijk, Belgium
| |
Collapse
|
24
|
Gareb B, van Munster VDM, Dijkstra PU, Bos RRM, Vissink A, van Bakelen NB, van Minnen B. Reliability and accuracy of the torque applied to osteosynthesis screws by maxillofacial surgeons and residents. Sci Rep 2022; 12:14411. [PMID: 36002589 PMCID: PMC9402715 DOI: 10.1038/s41598-022-18687-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 08/17/2022] [Indexed: 11/09/2022] Open
Abstract
Applying the right torque to osteosynthesis screws is important for undisturbed bone healing. This study aimed to compare test-retest and intra-individual reliabilities of the torque applied to 1.5 mm and 2.0 mm osteosynthesis screws by residents and oral and maxillofacial surgeons (OMF-surgeons), to define the reference torque intervals, and to compare reference torque interval compliances. Five experienced OMF-surgeons and 20 residents, 5 of each 4 residency years, were included. Each participant inserted six 1.5 × 4 mm and six 2.0 × 6 mm screws into a preclinical model at two test moments 2 weeks apart (T1 and T2). Participants were blinded for the applied torque. Descriptive statistics, reference intervals, and intra-class correlation coefficients (ICC) were calculated. The OMF-surgeons complied more to the reference intervals (1.5 mm screws: 95% and 2.0 mm screws: 100%) than the residents (82% and 90%, respectively; P = 0.009 and P = 0.007) with the ICCs ranging between 0.85-0.95 and 0.45-0.97, respectively. The residents' accuracy and reliability were inadequate regarding the 1.5 mm screws but both measures improved at T2 for both screw types compared to T1, indicating a learning effect. Training residents and/or verifying the applied torque by experienced OMF-surgeons remains necessary to achieve high accuracy and reliability, particularly for 1.5 mm screws.
Collapse
Affiliation(s)
- Barzi Gareb
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands.
| | - Valerie D M van Munster
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands
| | - Pieter U Dijkstra
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands.,Department of Rehabilitation Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Ruud R M Bos
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands
| | - Arjan Vissink
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands
| | - Nico B van Bakelen
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands
| | - Baucke van Minnen
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, P.O. Box 30001, 9700 RB, Groningen, The Netherlands
| |
Collapse
|
25
|
Dentin Particulate for Bone Regeneration: An In Vitro Study. Int J Mol Sci 2022; 23:ijms23169283. [PMID: 36012558 PMCID: PMC9408967 DOI: 10.3390/ijms23169283] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 11/23/2022] Open
Abstract
The aim of this in vitro study was to investigate the commitment and behavior of dental pulp stem cells (DPSCs) seeded onto two different grafting materials, human dentin particulate (DP) and deproteinized bovine bone matrix (BG), with those cultured in the absence of supplements. Gene expression analyses along with epigenetic and morphological tests were carried out to examine odontogenic and osteogenic differentiation and cell proliferation. Compressive testing of the grafting materials seeded with DPSCs was performed as well. DPSC differentiation into odontoblast-like cells was identified from the upregulation of odontogenic markers (DSPP and MSX) and osteogenic markers (RUNX2, alkaline phosphatase, osteonectin, osteocalcin, collagen type I, bmp2, smad5/8). Epigenetic tests confirmed the presence of miRNAs involved in odontogenic or osteogenic commitment of DPSCs cultured for up to 21 days on DP. Compressive strength values obtained from extracellular matrix (ECM) synthesized by DPSCs showed a trend of being higher when seeded onto DP than onto BG. High expression of VEGF factor, which is related to angiogenesis, and of dentin sialoprotein was observed only in the presence of DP. Morphological analyses confirmed the typical phenotype of adult odontoblasts. In conclusion, the odontogenic and osteogenic commitment of DPSCs and their respective functions can be achieved on DP, which enables exceptional dentin and bone regeneration.
Collapse
|
26
|
Validation of Experimental and Finite Element Biomechanical Evaluation of Human Cadaveric Mandibles. LUBRICANTS 2022. [DOI: 10.3390/lubricants10080169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Background: Biomechanical analysis of human mandible is important not only to understand mechanical behavior and structural properties, but also to diagnose and develop treatment options for mandibular disorders. Therefore, the objective of this research was to generate analytical and experimental data on mandibles, construct custom 3D models, and compare the analytically derived maximum strains with strain gage data in five areas of interest for each mandible. Methods: We investigated the surface strains in the cadaveric human mandibles under different configurations of cyclic compressive loads in an experimental setting and compared these experimental strain data with results derived from computational finite element analysis (FEA), accurately replicating the experiments. Strains on the surface of each mandible were measured with strain gauges, and subsequently a subject-specific finite element (FE) volume mesh was generated from computed tomography (CT) scans of each mandible. Strain patterns of each mandible were derived from the FEA simulating the experimental setup and matched with the experimental data. Findings: Analysis of experimental data showed that strain as measured at the condylar locations was significantly different from those at other locations on the mandible, and that the sex and age of the subject did not have a significant correlation with the strain. Comparing the FE numerical predictions with the experimental data, we found a good statistical correlation and statistical agreement between in-vitro measurements and FE results. Interpretation: The study demonstrates that our methodology of generating subject-specific FE models is a valid and accurate, non-invasive method to evaluate the complex biomechanical behavior of human mandibles.
Collapse
|
27
|
Li Y, Hu Y, Chen H, Meng X, Chen D, Gu H, Chen Q, Mu Z, Li Z. A novel conceptual design of a biomimetic oral implant and its biomechanical effect on the repairment of a large mandibular defect. MEDICINE IN NOVEL TECHNOLOGY AND DEVICES 2022. [DOI: 10.1016/j.medntd.2022.100147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
|
28
|
Simple anisotropic model of Bone Adaptation - SAMBA. J Mech Behav Biomed Mater 2022; 131:105217. [DOI: 10.1016/j.jmbbm.2022.105217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 03/26/2022] [Accepted: 04/02/2022] [Indexed: 11/20/2022]
|
29
|
Orassi V, Fischer H, Duda GN, Heiland M, Checa S, Rendenbach C. In Silico Biomechanical Evaluation of WE43 Magnesium Plates for Mandibular Fracture Fixation. Front Bioeng Biotechnol 2022; 9:803103. [PMID: 35223813 PMCID: PMC8866862 DOI: 10.3389/fbioe.2021.803103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/29/2021] [Indexed: 11/18/2022] Open
Abstract
Titanium fixation devices are the gold standard for the treatment of mandibular fractures; however, they present serious limitations, such as non-degradability and generation of imaging artifacts. As an alternative, biodegradable magnesium alloys have lately drawn attention due to their biodegradability and biocompatibility. In addition, magnesium alloys offer a relatively high modulus of elasticity in comparison to biodegradable polymers, being a potential option to substitute titanium in highly loaded anatomical areas, such as the mandible. This study aimed to evaluate the biomechanical competence of magnesium alloy WE43 plates for mandibular fracture fixation in comparison to the clinical standard or even softer polymer solutions. A 3D finite element model of the human mandible was developed, and four different fracture scenarios were simulated, together with physiological post-operative loading and boundary conditions. In a systematic comparison, the material properties of titanium alloy Ti-6Al-4V, magnesium alloy WE43, and polylactic acid (PLA) were assigned to the fixation devices, and two different plate thicknesses were tested. No failure was predicted in the fixation devices for any of the tested materials. Moreover, the magnesium and titanium fixation devices induced a similar amount of strain within the healing regions. On the other hand, the PLA devices led to higher mechanical strains within the healing region. Plate thickness only slightly influenced the primary fixation stability. Therefore, magnesium alloy WE43 fixation devices seem to provide a suitable biomechanical environment to support mandibular fracture healing in the early stages of bone healing. Magnesium WE43 showed a biomechanical performance similar to clinically used titanium devices with the added advantages of biodegradability and radiopacity, and at the same time it showed a remarkably higher primary stability compared to PLA fixation devices, which appear to be too unstable, especially in the posterior and more loaded mandibular fracture cases.
Collapse
Affiliation(s)
- Vincenzo Orassi
- Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany
| | - Heilwig Fischer
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Georg N. Duda
- Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Max Heiland
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sara Checa
- Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
- *Correspondence: Sara Checa,
| | - Carsten Rendenbach
- Department of Oral and Maxillofacial Surgery, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| |
Collapse
|
30
|
The Effectiveness of Dental Protection and the Material Arrangement in Custom-Made Mouthguards. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11209363] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Experimental research studies have shown that wearing a mouthguard (MG) is an effective way to prevent tooth or maxillofacial trauma. However, there is a lack of scientific information regarding how the material arrangement within the mouthguard can modify its mechanical response during an impact. Hence, this study aimed to evaluate the influence of material arrangement within custom-made mouthguards on stress transmitted to anterior teeth, bone, and soft tissue after impact. Four 3D finite element models of a human maxilla were reconstructed based on the CBCT of a young patient and analyzed according to the presence or absence of a mouthguard and the type of material arrangement within those with a mouthguard: model NMG with no mouthguard; model CMG representing the conventional arrangement with a single 4 mm-thick ethylene-vinyl acetate (EVA) foil; model FMG presenting layer arrangement with two 1 mm-thick foils of EVA in the outer shell and one 2 mm-thick foil of EVA foam in the core; model HMG presenting a 1 mm-thick compact inner and outer shell of EVA and a 2 mm wide air-filled zone in the core. Linear quasi-static analysis and frontal load were used to simulate an impact with an energy of 4.4 J. Isotropic linear elastic properties were assumed for the bone and teeth but not for the mouthguard protection and oral soft tissues. The results were evaluated and compared in terms of displacement, stretches, and stresses. All the mouthguards analyzed reduced the risk of injury to teeth and bone, reducing the displacement and stress of these structures. However, the implementation of a honeycomb structured layer allowed more significant displacement and deformation of the mouthguard’s external layer, thus promoting higher protection of the anatomic structures, namely the root dentin and the bone tissue. Nevertheless, the results also indicate that improving the mouthguard flexibility might increase the soft tissue injuries.
Collapse
|
31
|
Smith AL, Robinson C, Taylor AB, Panagiotopoulou O, Davis J, Ward CV, Kimbel WH, Alemseged Z, Ross CF. Comparative biomechanics of the Pan and Macaca mandibles during mastication: finite element modelling of loading, deformation and strain regimes. Interface Focus 2021; 11:20210031. [PMID: 34938438 PMCID: PMC8361577 DOI: 10.1098/rsfs.2021.0031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/09/2021] [Indexed: 10/17/2023] Open
Abstract
The mechanical behaviour of the mandibles of Pan and Macaca during mastication was compared using finite element modelling. Muscle forces were calculated using species-specific measures of physiological cross-sectional area and scaled using electromyographic estimates of muscle recruitment in Macaca. Loading regimes were compared using moments acting on the mandible and strain regimes were qualitatively compared using maps of principal, shear and axial strains. The enlarged and more vertically oriented temporalis and superficial masseter muscles of Pan result in larger sagittal and transverse bending moments on both working and balancing sides, and larger anteroposterior twisting moments on the working side. The mandible of Pan experiences higher principal strain magnitudes in the ramus and mandibular prominence, higher transverse shear strains in the top of the symphyseal region and working-side corpus, and a predominance of sagittal bending-related strains in the balancing-side mandible. This study lays the foundation for a broader comparative study of Hominidae mandibular mechanics in extant and fossil hominids using finite element modelling. Pan's larger and more vertical masseter and temporalis may make it a more suitable model for hominid mandibular biomechanics than Macaca.
Collapse
Affiliation(s)
- Amanda L. Smith
- Department of Anatomy, Pacific Northwest University of Health Sciences, 200 University Parkway, Yakima, WA 98901, USA
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, IL 60637, USA
| | - Chris Robinson
- Department of Biological Sciences, Bronx Community College, Bronx, NY 10453, USA
| | | | - Olga Panagiotopoulou
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Melbourne, Victoria 3800, Australia
| | - Julian Davis
- Department of Engineering, University of Southern Indiana, 8600 University Boulevard, Evansville, IN 47712, USA
| | - Carol V. Ward
- Department of Pathology and Anatomical Sciences, One Hospital Drive, University of Missouri, Columbia, MO 65212, USA
| | - William H. Kimbel
- School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85287-4101, USA
| | - Zeresenay Alemseged
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, IL 60637, USA
| | - Callum F. Ross
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 East 57th Street, Chicago, IL 60637, USA
| |
Collapse
|
32
|
Benevides F, Cimões R, Vajgel A, Wilmersdorf RB, Vajgel BDCF. Stress evaluation of different implant lengths on atrophic edentulous mandibles with fixed full-arch implant-supported prosthesis: a finite element analysis. Comput Methods Biomech Biomed Engin 2021; 24:358-374. [PMID: 34121526 DOI: 10.1080/10255842.2020.1817406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Finite element analysis was used to compare the effect of different implant lengths on atrophic mandible with full-arch fixed prostheses. Four models were constructed with different implant lengths: 4, 6, 8 and 10 mm. A 100-N occlusal load was applied. The stress at the bone level, implant, and prosthetic components were obtained. Similar behavior was observed for all groups, except for 4 mm, which showed more discrepant values for all prosthetic components. Although longer implants presented better biomechanical behavior, the 4 mm implant seems to be a viable alternative for severely atrophic mandibles, however, further studies need to be carried out.
Collapse
Affiliation(s)
| | - Renata Cimões
- Department of Prosthesis and Oral Facial Surgery, Federal University of Pernambuco, Recife, Brazil
| | - André Vajgel
- University of Pernambuco, School of Dentistry, Arcoverde, PE, Brazil
| | | | | |
Collapse
|
33
|
Orassi V, Duda GN, Heiland M, Fischer H, Rendenbach C, Checa S. Biomechanical Assessment of the Validity of Sheep as a Preclinical Model for Testing Mandibular Fracture Fixation Devices. Front Bioeng Biotechnol 2021; 9:672176. [PMID: 34026745 PMCID: PMC8134672 DOI: 10.3389/fbioe.2021.672176] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/13/2021] [Indexed: 11/13/2022] Open
Abstract
Mandibular fracture fixation and reconstruction are usually performed using titanium plates and screws, however, there is a need to improve current fixation techniques. Animal models represent an important step for the testing of new designs and materials. However, the validity of those preclinical models in terms of implant biomechanics remains largely unknown. In this study, we investigate the biomechanics of the sheep mandible as a preclinical model for testing the mechanical strength of fixation devices and the biomechanical environment induced on mandibular fractures. We aimed to assess the comparability of the biomechanical conditions in the sheep mandible as a preclinical model for human applications of fracture fixation devices and empower analyses of the effect of such defined mechanical conditions on bone healing outcome. We developed 3D finite element models of the human and sheep mandibles simulating physiological muscular loads and three different clenching tasks (intercuspal, incisal, and unilateral). Furthermore, we simulated fractures in the human mandibular body, sheep mandibular body, and sheep mandibular diastema fixated with clinically used titanium miniplates and screws. We compared, at the power stroke of mastication, the biomechanical environment (1) in the healthy mandibular body and (2) at the fracture sites, and (3) the mechanical solicitation of the implants as well as the mechanical conditions for bone healing in such cases. In the healthy mandibles, the sheep mandibular body showed lower mechanical strains compared to the human mandibular body. In the fractured mandibles, strains within a fracture gap in sheep were generally not comparable to humans, while similar or lower mechanical solicitation of the fixation devices was found between the human mandibular body fracture and the sheep mandibular diastema fracture scenarios. We, therefore, conclude that the mechanical environments of mandibular fractures in humans and sheep differ and our analyses suggest that the sheep mandibular bone should be carefully re-considered as a model system to study the effect of fixation devices on the healing outcome. In our analyses, the sheep mandibular diastema showed similar mechanical conditions for fracture fixation devices to those in humans.
Collapse
Affiliation(s)
- Vincenzo Orassi
- Julius Wolff Institute, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.,Department of Oral and Maxillofacial Surgery, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany
| | - Georg N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Max Heiland
- Department of Oral and Maxillofacial Surgery, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Heilwig Fischer
- Julius Wolff Institute, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.,Department of Oral and Maxillofacial Surgery, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Carsten Rendenbach
- Department of Oral and Maxillofacial Surgery, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sara Checa
- Julius Wolff Institute, Charité - Universitätsmedizin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| |
Collapse
|
34
|
Influence of Cavity Geometry on the Fracture Strength of Dental Restorations: Finite Element Study. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11094218] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The main purpose of this work was to analyze the stress distribution in premolars restored with indirect IPS Empress® CAD onlays or inlays. The three-dimensional geometry of a human first premolar was created using modeling software. The tooth fixation system was simulated through box geometry, comprising a cortical bone layer with 2 mm of thickness over a layer of trabecular bone with 15 mm of thickness. The tooth had the following approximated crown dimensions: 10.35 mm buccolingual length; 7.1 mm mesiodistal width; and 7.0 mm cervico-occlusal height. The mesio-occluso-distal (MOD) cavity preparations followed the suggestions available in the literature. The cement geometry was modified to include cohesive zone models (CZM) to perform the adhesive joint’s strength prediction. The loading body was created assuming contact between the food bolus and the tooth surface. Numerical solutions were obtained by performing static analysis and damage analysis using the finite element method. Von Mises stress values generated in the ceramic inlay restoration ranged from 1.39–181.47 MPa, which were on average 4.4% higher than those of the onlay ceramic restoration. The fracture strength of the onlay restoration was about 18% higher than that of the inlay restoration. The onlay design seems to contribute to higher homogenization of the adhesive resin cement strain and higher tooth structure protection.
Collapse
|
35
|
Ashry A, Elattar MS, Elsamni OA, Soliman IS. Effect of Guiding Sleeve Design on Intraosseous Heat Generation During Implant Site Preparation (In Vitro Study). J Prosthodont 2021; 31:147-154. [PMID: 33942432 DOI: 10.1111/jopr.13370] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2021] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To compare the effect of different designs of guiding sleeves on heat generation during implant surgery while using different cooling fluid temperatures. MATERIAL AND METHODS Temperature measurements were performed during guided implant site preparation in bovine rib samples using two K- type thermocouples at 2 mm and 8 mm depths. Three groups were tested according to guiding sleeve design: conventional cylindrical sleeve, open C-shaped sleeve, and modified cylindrical sleeve. Each group was irrigated with three fluid temperatures: 10°C, 15°C, and 20°C. The groups were compared using Kruskal Wallis test followed by post hoc comparisons with Bonferroni correction. The level of statistical significance was set at p = 0.05. RESULTS Surgical guides with conventional cylindrical sleeve design showed significantly higher heat generation during implant site preparation than guides with both the open C-shaped and the modified cylindrical sleeve designs at both 2mm and 8mm depths. The difference between C-shaped and modified cylindrical sleeves was not significant in any group. Using pre-cooled irrigation fluids (10°C and 15°C) reduced the generated heat; however, the differences within the same group were not statistically significant. CONCLUSIONS The use of a surgical guide with the conventional cylindrical sleeves led to higher heat generation than other sleeve designs, which might reach or near the critical threshold of bone thermal necrosis. Using surgical guides with open sleeves or modified cylindrical sleeves could be helpful in irrigation fluid delivery and decreasing the generated heat.
Collapse
Affiliation(s)
- Amal Ashry
- Prosthodontics Department, Faculty of Dentistry, Damanhour University, Damanhour, Egypt.,Prosthodontics Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| | | | - Osama Ahmed Elsamni
- Mechanical Engineering Department, Faculty of Engineering, Alexandria University, Alexandria, Egypt
| | - Ingy Saied Soliman
- Prosthodontics Department, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| |
Collapse
|
36
|
Chen S, Rittel D, Shemtov Yona K. The normal stiffness of the edentulous alveolar process. Bone Rep 2021; 14:101066. [PMID: 33898661 PMCID: PMC8060551 DOI: 10.1016/j.bonr.2021.101066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 04/06/2021] [Indexed: 11/26/2022] Open
Abstract
The normal stiffness of the jawbone is seldom considered, as opposed to the mechanical properties of its individual cortical and trabecular components. Our standpoint is essentially structural, rather than purely material-oriented, as the jawbone is considered as a natural load-bearing structure. Throughout the work, 3 representative sections in the mandible and the maxilla are modelled and compared. Specifically, we evaluate the sections' elastic structural stiffness numerically, according to the recent geometrical classification proposed by Shemtov Yona (2021). Each case is modelled using two extreme configurations for the cortical-trabecular interaction, namely bonded and unbonded. Those two configurations reflect extreme interfacial conditions, though the bonded one is more physical. For the unbonded cases, the structural stiffness is the sum of the individual stiffnesses of the components. By sharp contrast, the bonded case results in a much larger stiffness than that obtained by the simple sum of the individual stiffnesses, indicating a strong synergistic stiffening effect between the components through their interface. We also investigate the role of the elastic moduli, whose reported values vary widely in the literature, emphasizing the role of the trabecular Poisson's coefficient, whose stiffening effect is evidenced when it exceeds about 0.3. The bone's structural stiffness shown here complements the geometrical classification of the jawbone types with a fundamental mechanical/structural property delineating the coupling between the mechanical properties and the geometry. The adopted approach is not limited to the jawbone and applies in principle to other bone types. From a clinical standpoint, the results presented here complement not only the basic mechanical aspects of the geometrical characterization, but also provide a starting point for future studies on dental implant placement and stability, the latter being directly related to the structural stiffness.
Collapse
Affiliation(s)
- S Chen
- Mechanical Engineering Faculty, Technion, Israel Institute of Technology, Haifa, Israel
| | - D Rittel
- Mechanical Engineering Faculty, Technion, Israel Institute of Technology, Haifa, Israel
| | - K Shemtov Yona
- Mechanical Engineering Faculty, Technion, Israel Institute of Technology, Haifa, Israel.,The Maurice and Gabriela Goldschleger School of Dental Medicine, Department of Oral Biology, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
37
|
Effects of premature contact in maxillary alveolar bone in rats: relationship between experimental analyses and a micro scale FEA computational simulation study. Clin Oral Investig 2021; 25:5479-5492. [PMID: 33641062 DOI: 10.1007/s00784-021-03856-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 02/22/2021] [Indexed: 10/22/2022]
Abstract
OBJECTIVE The aim of the investigation was to evaluate the maxillary alveolar bone morphology, bone architecture, and bone turnover in relation to the mechanical strain distribution in rats with dental premature contact. MATERIALS AND METHODS Fifty 2-month-old male Wistar rats were used. The premature contact group (N=40) received a unilateral (right side) resin cementation on the occlusal surface of the upper first molar. The animals were distributed in 4 subgroups according to the periods of euthanasia: 7, 14, 21, and 28 days after cementation (N=10, for each period). For the control group (N=10), the teeth were kept without resin, featuring a normal occlusion. The pieces including the upper first molars, alveolar bone, and periodontal tissue were processed to histological and immunohistochemical evaluation of RANK-L and TRAP protein expression. A three-dimensional bone microarchitecture analysis was performed, where the heads of animals were scanned using microtomography and analyzed using CT-Analyser software (Bruker, Kontich, Belgium). In the computer simulation by finite element analysis, two micro-scaled three-dimensional finite element models of first molar and dentoalveolar tissues were constructed, in representation of control and premature contact groups, using Materialise MIMICS Academic Research v18 (Materialise, Leuven, Belgium). The analysis was set to simulate a maxillary molar biting during the power stroke phase. The total deformation, equivalent strain, and minimum principal strain distribution were calculated. RESULTS The expression of RANK-L and TRAP presented higher positive ratio in the 7-day period compared to the control group. The three-dimensional morphometry showed decrease of bone volume in the premature contact, with significant values between the control and the 7-day and 14-day groups (P = 0.007). In FEA, the premature contact model presented a uniform compressive strain distribution in the alveolar bone crest compared to a non-uniform compressive strain distribution in the control model. CONCLUSIONS The results from FEA, 3D bone microarchitecture, and histological and immunohistochemical analyses showed that a model with dental traumatic occlusion resulted in changes of alveolar bone mechanobiology and, consequently, its morphology. CLINICAL RELEVANCE These results could be applied in dental treatment planning bringing biological and mechanical feedback to provide an effective mechanism to obtain physiological bone loss responses. Furthermore, this association between experimental and computational analyses will be important to figure out the alveolar bone response to mechanical stimulation in different clinical conditions.
Collapse
|
38
|
Vukicevic AM, Zelic K, Milasinovic D, Sarrami-Foroushani A, Jovicic G, Milovanovic P, Djuric M, Filipovic N, Frangi AF. OpenMandible: An open-source framework for highly realistic numerical modelling of lower mandible physiology. Dent Mater 2021; 37:612-624. [PMID: 33602549 DOI: 10.1016/j.dental.2021.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 01/10/2021] [Accepted: 01/18/2021] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Computer modeling of lower mandible physiology remains challenging because prescribing realistic material characteristics and boundary conditions from medical scans requires advanced equipment and skill sets. The objective of this study is to provide a framework that could reduce simplifications made and inconsistency (in terms of geometry, materials, and boundary conditions) among further studies on the topic. METHODS The OpenMandible framework offers: 1) the first publicly available multiscale model of the mandible developed by combining cone beam computerized tomography (CBCT) and μCT imaging modalities, and 2) a C++ software tool for the generation of simulation-ready models (tet4 and hex8 elements). In addition to the application of conventional (Neumann and Dirichlet) boundary conditions, OpenMandible introduces a novel geodesic wave propagation - based approach for incorporating orthotropic micromechanical characteristics of cortical bone, and a unique algorithm for modeling muscles as uniformly directed vectors. The base intact model includes the mandible (spongy and compact bone), 14 teeth (comprising dentin, enamel, periodontal ligament, and pulp), simplified temporomandibular joints, and masticatory muscles (masseter, temporalis, medial, and lateral pterygoid). RESULTS The complete source code, executables, showcases, and sample data are freely available on the public repository: https://github.com/ArsoVukicevic/OpenMandible. It has been demonstrated that by slightly editing the baseline model, one can study different "virtual" treatments or diseases, including tooth restoration, placement of implants, mandible bone degradation, and others. SIGNIFICANCE OpenMandible eases the community to undertake a broad range of studies on the topic, while increasing their consistency and reproducibility. At the same time, the needs for dedicated equipment and skills for developing realistic simulation models are significantly reduced.
Collapse
Affiliation(s)
- Arso M Vukicevic
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia.
| | - Ksenija Zelic
- Laboratory for Anthropology, Institute of Anatomy, School of Medicine, University of Belgrade, Belgrade, Serbia; School of Dental Medicine, University of Belgrade, Belgrade, Serbia
| | - Danko Milasinovic
- Faculty of Hotel Management and Tourism in Vrnjačka Banja, University of Kragujevac, Vrnjacka Banja, Serbia
| | - Ali Sarrami-Foroushani
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), School of Computing and School of Medicine, University of Leeds, Leeds, UK; Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, UK
| | - Gordana Jovicic
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
| | - Petar Milovanovic
- Laboratory for Anthropology, Institute of Anatomy, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Marija Djuric
- Laboratory for Anthropology, Institute of Anatomy, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Nenad Filipovic
- Faculty of Engineering, University of Kragujevac, Kragujevac, Serbia
| | - Alejandro F Frangi
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), School of Computing and School of Medicine, University of Leeds, Leeds, UK; Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, UK; Medical Imaging Research Center (MIRC), University Hospital Gasthuisberg, Cardiovascular Sciences and Electrical Engineering Departments, KU Leuven, Leuven, Belgium
| |
Collapse
|
39
|
Mechanical Evaluation of Implant-Assisted Removable Partial Dentures in Kennedy Class I Patients: Finite Element Design Considerations. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11020659] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The main purpose of this work was to construct a clinically valid numerical model of a mandibular Kennedy class I patient rehabilitated with a conventional removable partial denture and another two with implant-assisted removable partial dentures at two different implant locations. The selected patient was classified as ASA I and its mandible geometry reconstruction was performed by the conversion of the Cone-Beam computed Tomography (CBCT) scan raw medical data into a 3D model and subsequent conversion to a CAD file by reverse engineering methods. The soft tissue and removable denture geometries were also included in the CAD model as well as implants, ball attachments and matrix. Moreover, periodontal ligament was modelled by offsetting the mesh of the root surface of each tooth. The finite element results showed that the installation of a dental implant in each of the bilateral edentulous regions helps providing support and retention to the extension bases of the Removable Partial Denture (RPD) and significantly reduces the vertical and anterior-posterior displacements, regardless of its position.
Collapse
|
40
|
KARGARNEJAD SAHAND, GHALICHI FARZAN, POURGOL-MOHAMMAD MOHAMMAD, OSKUI IZ, GARAJEI ATA. BIOMECHANICAL EVALUATION OF RECONSTRUCTED EXTENSIVE MANDIBULAR DEFECTS BY DIFFERENT MODELS USING FINITE ELEMENT METHOD. J MECH MED BIOL 2020. [DOI: 10.1142/s0219519420500530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Rehabilitation of major mandibular defects after tumor resection has become a serious challenge for surgeons. In this research, four various models were designed to repair a critical mandibular lateral defect. Biomechanical behavior of the models was assessed by Finite Element Method. These models are including Fibular-Free Flap (FFF), Customized Prosthesis (CP), Tray Implant without Bone Graft (TI-wo-BG), and Tray Implant with Bone Graft (TI-w-BG). FFF is a subset of microvascular free flap technique in which some segments of patient’s fibula bone are used to restore mandibular defects. CP is a hollow and light prosthesis which is fabricated using Additive Manufacturing technology from Ti alloy powder. TI-wo-BG is similar to a crib which is designed according to the geometry of the patient’s mandible. TI-w-BG, in fact, is a TI-wo-BG which is filled with small cortico-cancellous chips in order to benefit potential profit of bone grafting. The chewing operation and loading on the mandible was simulated considering the three mandibular muscular forces including masseter, medial pterygoid, and temporalis. The result of FEM analysis of TI-wo-BG and TI-w-BG showed that in both models, screw number 6 endured a strain of 5684 and 2852[Formula: see text][Formula: see text]m/m which exceeded pathological and mild overload risk, respectively. This may increase the probability of screw loosening and system failure. The results proved the stability of the FFF and CP models. In addition, it can be concluded that stress and strain on the screw’s interfaces can decrease by improving the plate and increasing the friction at the interface of plate, bone and screw.
Collapse
Affiliation(s)
- SAHAND KARGARNEJAD
- Faculty of Biomedical Engineering, Sahand University of Technology, P.O. Box: 51335/1996, Sahand New Town, Tabriz, Iran
| | - FARZAN GHALICHI
- Faculty of Biomedical Engineering, Sahand University of Technology, P.O. Box: 51335/1996, Sahand New Town, Tabriz, Iran
| | - MOHAMMAD POURGOL-MOHAMMAD
- Mechanical Engineering Department, Sahand University of Technology, P.O. Box: 51335/1996, Sahand New Town, Tabriz, Iran
| | - I. Z. OSKUI
- Faculty of Biomedical Engineering, Sahand University of Technology, P.O. Box: 51335/1996, Sahand New Town, Tabriz, Iran
| | - ATA GARAJEI
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran, Iran
- The Cancer Institute, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- The Cancer Institute, Imam Hospital Complex, Keshavarz Blvd., Tehran, Iran
| |
Collapse
|
41
|
Koper DC, Leung CAW, Smeets LCP, Laeven PFJ, Tuijthof GJM, Kessler PAWH. Topology optimization of a mandibular reconstruction plate and biomechanical validation. J Mech Behav Biomed Mater 2020; 113:104157. [PMID: 33187871 DOI: 10.1016/j.jmbbm.2020.104157] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 10/18/2020] [Accepted: 10/22/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Reconstruction plates, used to bridge segmental defects of the mandible after tumor resection or traumatic bone tissue loss, are subjected to repeated stresses of mastication. High stress concentrations in these plates can result in hardware failure. Topology optimization (TO) could reduce the peak stress by computing the most optimal material distribution in a patient-specific implant (PSI) used for mandibular reconstruction. The objective of this study was biomechanical validation of a TO-PSI. METHODS A computer-aided design (CAD) model with a segmental defect was created based on the geometry of a polyurethane mandible model. A standard-PSI was designed to bridge the defect. A TO-PSI was then designed with a maximum stress equal to the ultimate tensile stress of Ti6Al4V (930 MPa) during a loading condition of 378 N. Finite element analysis (FEA) was used to analyze stresses in both PSI designs during loading. The standard-PSI and TO-PSI designs were produced in triplicate by selective laser melting of Ti6Al4V, fixated to polyurethane mandible models with segmental defects identical to the CAD model, and subsequently subjected to continuous compression with a speed of 1 mm/min on a universal testing machine, while recording the load. Peak loads before failure in the TO-PSI group within a 30% range of the predicted peak load (378 N) were considered a successful biomechanical validation. RESULTS Fracture of the TO-PSI occurred at a median peak load of 334 N (range 304-336 N). These values are within the 30% range of the predicted peak load. Fracture of the mandible model in the standard-PSI group occurred at a median peak load of 1100 N (range 1010-1460 N). Failure locations during biomechanical testing of TO-PSI and standard-PSI samples corresponded to regions in the FEA where stresses exceeded the ultimate tensile strength of titanium and polyurethane, respectively. CONCLUSION This study demonstrates a successful preliminary biomechanical validation of TO in the design process for mandibular reconstruction plates. Further work is needed to refine the finite element model, which is necessary to ultimately design TO-PSIs for clinical use.
Collapse
Affiliation(s)
- David C Koper
- Department of Cranio-Maxillofacial Surgery, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, the Netherlands; Department of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands; Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands.
| | - Carine A W Leung
- Department of Cranio-Maxillofacial Surgery, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, the Netherlands
| | - Lars C P Smeets
- Department of Instrument Design, Engineering and Evaluation, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands
| | - Paul F J Laeven
- Department of Instrument Design, Engineering and Evaluation, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands
| | - Gabriëlle J M Tuijthof
- Department of Instrument Design, Engineering and Evaluation, Maastricht University, PO Box 616, 6200 MD, Maastricht, the Netherlands
| | - Peter A W H Kessler
- Department of Cranio-Maxillofacial Surgery, Maastricht University Medical Center, PO Box 5800, 6202 AZ, Maastricht, the Netherlands
| |
Collapse
|
42
|
Humphries LS, Reid RR, Ross CF, Taylor AB, Collins JM, Freire AR, Rossi AC, Prado FB. Biomechanical and morphological analysis of Pierre Robin sequence mandible: Finite element and morphometric study. Anat Rec (Hoboken) 2020; 304:1375-1388. [PMID: 33099874 DOI: 10.1002/ar.24543] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 08/19/2020] [Accepted: 08/22/2020] [Indexed: 11/06/2022]
Affiliation(s)
- Laura S Humphries
- Department of Surgery, Section of Plastic and Reconstructive Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Russell R Reid
- Department of Surgery, Section of Plastic and Reconstructive Surgery, University of Chicago Medicine, Chicago, Illinois, USA
| | - Callum F Ross
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, USA
| | - Andrea B Taylor
- Department of Basic Science, Touro University, Vallejo, California, USA
| | - John M Collins
- Department of Radiology, University of Chicago Medicine, Chicago, Illinois, USA
| | - Alexandre R Freire
- Department of Biosciences-Anatomy, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil
| | - Ana Cláudia Rossi
- Department of Biosciences-Anatomy, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil
| | - Felippe B Prado
- Department of Biosciences-Anatomy, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil
| |
Collapse
|
43
|
Kase T, Ohyama T, Nakabayashi S, Yasuda H, Yoneyama T. Mechanical effects of residual bone mass, a maxillofacial prosthesis, and a reconstruction plate on the mandible after marginal resection. J Oral Sci 2020; 62:377-381. [PMID: 32741850 DOI: 10.2334/josnusd.19-0427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
In this study, analytic models were used to simulate marginal resection in the area of the second premolar to the second molar region, and the mechanical effects on the mandible of residual bone mass, a maxillofacial prosthesis, and a reconstruction plate were evaluated by three-dimensional finite element analysis. As residual bone mass decreased, maximum principal stress increased near the anterior ramus of the mandible, and maximum shear stress increased at the anterior buccal region of the resected area. In the mandible with a maxillofacial prosthesis, the maximum principal stress distribution at the anterior ramus was lower, and the distribution of maximum shear stress at the anterior buccal region of the resected area was higher. When a reconstruction plate was used, maximum principal stress and maximum shear stress were lower. Thus, lower residual bone mass was associated with increased mandible deflection and torsion. In addition, presence of a maxillofacial prosthesis decreased deflection but increased torsion, and presence of a reconstruction plate decreased deflection and greatly decreased torsion. These findings suggest that decreased residual bone mass and maxillofacial prostheses increase fracture risk; however, presence of a reconstruction plate was effective in decreasing torsional stress, thereby reducing fracture risk in the mandible.
Collapse
Affiliation(s)
- Takeshi Kase
- Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry
| | - Tetsuo Ohyama
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry.,Division of Clinical Research, Dental Research Center, Nihon University School of Dentistry
| | - Shinya Nakabayashi
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry.,Division of Clinical Research, Dental Research Center, Nihon University School of Dentistry
| | - Hiroyasu Yasuda
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry.,Division of Clinical Research, Dental Research Center, Nihon University School of Dentistry
| | - Takayuki Yoneyama
- Department of Dental Materials, Nihon University School of Dentistry.,Division of Biomaterial Science, Dental Research Center, Nihon University School of Dentistry
| |
Collapse
|
44
|
Krennmair S, Hunger S, Postl L, Winterhalder P, Holberg S, Malek M, Rudzki I, Holberg C. Edentulous mandible with four splinted interforaminal implants exposed to three different situations of trauma: A preliminary three‐dimensional finite element analysis. Dent Traumatol 2020; 36:607-617. [DOI: 10.1111/edt.12575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/01/2022]
Affiliation(s)
- Stefan Krennmair
- NumBioLab Department of Orthodontics Ludwig‐Maximilians University of Munich Munich Germany
| | - Stefan Hunger
- Department of Oral and Maxillofacial Surgery Johannes Kepler University Linz Linz Austria
| | - Lukas Postl
- NumBioLab Department of Orthodontics Ludwig‐Maximilians University of Munich Munich Germany
- Department of Oral and Maxillofacial Surgery Johannes Kepler University Linz Linz Austria
| | - Philipp Winterhalder
- Department of Oral and Maxillofacial Surgery RWTH Aachen University Aachen Germany
| | - Svenia Holberg
- NumBioLab Department of Orthodontics Ludwig‐Maximilians University of Munich Munich Germany
| | - Michael Malek
- Department of Oral and Maxillofacial Surgery Johannes Kepler University Linz Linz Austria
| | - Ingrid Rudzki
- NumBioLab Department of Orthodontics Ludwig‐Maximilians University of Munich Munich Germany
| | - Christof Holberg
- NumBioLab Department of Orthodontics Ludwig‐Maximilians University of Munich Munich Germany
| |
Collapse
|
45
|
Merema BBJ, Kraeima J, Glas HH, Spijkervet FKL, Witjes MJH. Patient-specific finite element models of the human mandible: Lack of consensus on current set-ups. Oral Dis 2020; 27:42-51. [PMID: 32372548 PMCID: PMC7818111 DOI: 10.1111/odi.13381] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 04/21/2020] [Accepted: 04/24/2020] [Indexed: 11/28/2022]
Abstract
The use of finite element analysis (FEA) has increased rapidly over the last decennia and has become a popular tool to design implants, osteosynthesis plates and prostheses. With increasing computer capacity and the availability of software applications, it has become easier to employ the FEA. However, there seems to be no consensus on the input variables that should be applied to representative FEA models of the human mandible. This review aims to find a consensus on how to define the representative input factors for a FEA model of the human mandible. A literature search carried out in the PubMed and Embase database resulted in 137 matches. Seven papers were included in this current study. Within the search results, only a few FEA models had been validated. The material properties and FEA approaches varied considerably, and the available validations are not strong enough for a general consensus. Further validations are required, preferably using the same measuring workflow to obtain insight into the broad array of mandibular variations. A lot of work is still required to establish validated FEA settings and to prevent assumptions when it comes to FEA applications.
Collapse
Affiliation(s)
- Bram Barteld Jan Merema
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands
| | - Joep Kraeima
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands
| | - Haye H Glas
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands
| | - Fred K L Spijkervet
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands
| | - Max J H Witjes
- Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands
| |
Collapse
|
46
|
Toniolo I, Salmaso C, Bruno G, De Stefani A, Stefanini C, Gracco ALT, Carniel EL. Anisotropic computational modelling of bony structures from CT data: An almost automatic procedure. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 189:105319. [PMID: 31951872 DOI: 10.1016/j.cmpb.2020.105319] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/27/2019] [Accepted: 01/05/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE The use of modelling techniques that combine CT data and bone tissue micromechanics is spreading in computational biomechanics. Finite Element models show great potential in surgical planning of intervention and in prediction of stress and strain fields through a non-invasive method. The main challenge pertains to the reliable characterization of bone mechanical behaviour. An almost automatic procedure is here defined, which provides computational models of bony structures considering the actual anisotropy of bone tissue response. The innovative aspect resides on the automatic detection of the directions of anisotropy as the eigenvectors of a three-dimensional distribution matrix of HU values. METHODS The procedure combines CT data and micromechanics modelling techniques. Regarding a specific location, the procedure reports both the orthotropic elastic constants, by the analysis of the local HU value, and the anisotropic material directions, by the analysis of the HU values distribution around the specific location. RESULTS The procedure returns the distribution of bone tissue orthotropic elasticity tensor. The procedure proves to correctly respect the differentiation between cortical and trabecular bone. Principal directions show to be consistent with experimental data from ultrasound measurements. Regarding the material mapping from voxel to FE model, the developed strategies show to be reliable, leading to marginal errors (lower than 10%) for most of CT voxels (more than 90%). The computational analyses of typical structural loading conditions lead to strain values that are comparable with results from strain gauges experimentations. The development and the exploitation of FE models of different bony structures allow assessing the reliability of the procedure for cortical bone. CONCLUSIONS The results highlight the potentialities of the procedure in providing accurate patient-specific biomechanical models of bony structures starting from CT data. The accuracy and the automatism of the procedure are important factors for the development of real time clinical tools. The main limitations of this work remain the not fully automatism and the reliability assessment, which is based mainly on cortical bone regions only.
Collapse
Affiliation(s)
- Ilaria Toniolo
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy; Department of Industrial Engineering, University of Padova, Italy.
| | - Claudia Salmaso
- Department of Industrial Engineering, University of Padova, Italy
| | - Giovanni Bruno
- Department of Neurosciences, University of Padova, Italy
| | | | - Cesare Stefanini
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
| | | | - Emanuele Luigi Carniel
- Department of Industrial Engineering, University of Padova, Italy; Centre for Mechanics of Biological Materials, University of Padova, Italy
| |
Collapse
|
47
|
Geraets WG, Jonasson G, Hakeberg M. Changing trabecular patterns in panoramic radiographs of Swedish women during 25 years of follow-up. Dentomaxillofac Radiol 2020; 49:20190494. [PMID: 32207990 DOI: 10.1259/dmfr.20190494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES The radiographic trabecular pattern on dental radiographs may be used to predict fractures. The aim of this study was to analyze longitudinal changes in the mandibles of 145 females between 1980 and 2005. METHODS Panoramic radiographs were obtained in 1980 and 2005. On 290 radiographs, regions of interest (ROIs) were selected in the ramus, angle and body. In all ROIs, the orientation was measured in 36 directions with the line frequency deviation method. The effects of ageing were analyzed for the fracture and the non-fracture groups separately. RESULTS During the follow-up, 61 females suffered fractures of the hip, wrist, spine, leg or arm. The fracture and non-fracture groups displayed dissimilar age changes in each investigated ROI. All significant changes pertained to increasing values of line frequency deviation. With increasing age, the trabecular network in the mandible lost details and the trabeculae became more aligned in their main direction. In the "ramus", the alignment was to the 110-120˚ axis, parallel to the posterior and anterior ramus border. In the "angle", the alignment was to the 135-150˚ axis, parallel to the oblique line, and in the "body" ROI to the 150-175˚ direction, approximately parallel to the occlusal plane and inferior cortex. CONCLUSION Most changes were consistent with the notion that the bone aged less severely in the non-fracture group. In the fracture group, the findings indicate that bone loss leads to redistribution of the remaining bone tissue in such a way that the trabeculae are accentuated perpendicular to the principal loading.
Collapse
Affiliation(s)
- Wil Gm Geraets
- Department of Oral Radiology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands
| | - Grethe Jonasson
- Research & Development Unit in Southern Ӓlvsborg County, Sven Eriksonplatsen 4, SE-50338 Borås, Sweden.,Department of Behavioral and Community Dentistry, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Box 450, 405 30 Gothenburg, Sweden
| | - Magnus Hakeberg
- Department of Behavioral and Community Dentistry, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Box 450, 405 30 Gothenburg, Sweden
| |
Collapse
|
48
|
Evaluation of condylar cortical bone thickness in patient groups with different vertical facial dimensions using cone-beam computed tomography. Odontology 2020; 108:669-675. [PMID: 32236830 DOI: 10.1007/s10266-020-00510-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 03/04/2020] [Indexed: 10/24/2022]
Abstract
The aim of this study is to evaluate through computed tomography differences in cortical plate thickness of condyle in patients with a different facial vertical skeletal pattern. The final sample of this retrospective study included CBCT exams of 60 adult subjects (mean age 33.2 ± 5.6), selected from the digital archive of a private practice. The subjects were assigned to 3 different groups according to the values of the Frankfurt-mandibular plane angle: hyper-, normo-, and hypodivergent groups. The volume rendering of the mandible was obtained and three condylar points were marked on it: median pole, lateral pole and the most cranial point. For each considered reference point, the minimum distance between external and internal cortical surface was measured, obtaining three different outcomes: condylar cortical bone thickness of median pole (CCBToMP), lateral pole (CCBToLP) and cranial pole (CCBToCP). The measurements were executed by means of Mimics software by the same expert operator in specific scan views. The cortical bone thickness of hyperdivergent patients was found to be statistically thicker than normodivergent patients and hypodivergent patients. Cortical bone thickness of normodivergent patients was found thicker than hypodivergent patients. All the differences were statistically significant (p < 0.05). The Pearson correlation coefficient showed a statistically significant correlation (p < 0.001) between the Frankfurt-mandibular plane angle and the evaluated cortical bone thickness outcomes. Facial biotype characteristics that define vertical facial skeletal pattern affect the cortical bone thickness of mandibular condyle.
Collapse
|
49
|
Krennmair S, Winterhalder P, Hunger S, Rupperti S, Holberg C. The Effects of Frontal Trauma on 4 Interforaminal Dental Implants: A 3-Dimensional Finite Element Analysis Comparing Splinted and Unsplinted Implant Configurations. J Oral Maxillofac Surg 2020; 78:961-972. [PMID: 31951811 DOI: 10.1016/j.joms.2019.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 12/09/2019] [Accepted: 12/09/2019] [Indexed: 11/18/2022]
Abstract
PURPOSE With increased implant-prosthodontic rehabilitation for mandibular edentulism together with the increased life expectancy and activity of the elderly population, a greater number of implant patients may be at risk of facial trauma. The aim of this 3-dimensional (3D) finite element analysis (FEA) was to evaluate the biomechanical effects of the edentulous mandible (EM) with and without implants exposed to frontal facial trauma including assessment of the fracture risk of different mandibular areas. MATERIALS AND METHODS By use of a 3D FEA, our experimental study design comprised 3 different models (model A, EM; model B, EM with 4 unsplinted interforaminal implants; and model C, EM with 4 splinted interforaminal implants) exposed to application of symphyseal frontal trauma of 2 MPa. In 3 defined regions of interest (ROIs) (ROI 1, symphyseal area; ROI 2, mental foraminal area; and ROI 3, condylar neck), the effective stress was measured at predefined sites in the superficial cortical mandibular area. The stress values of all ROIs evaluated were compared within each model (intramodel) as well as between the 3 models (intermodel). RESULTS For all models evaluated, a frontal traumatic load generated the highest stress levels in the condylar neck. However, for both models with implants (models B and C), the stress values were reduced significantly (P < .01) in the condylar neck region (ROI 3) but increased significantly (P < .001) in the mental foraminal area (ROI 2) compared with the EM model without implants. For the symphyseal area (ROI 1) evaluated, the unsplinted 4-implant model (model B) presented significantly (P < .001) higher stress values than the splinted implant model (model C) when frontal forces were applied. CONCLUSIONS Regardless of splinting or lack of splinting of 4 interforaminal implants, force absorption or transmission may shift the predominant risk factor from the condylar neck to the corpus or foramen mandibulae. However, splinting of 4 interforaminal implants may be beneficial in reducing the risk of bone fracture by providing protection for anterior risk situations.
Collapse
Affiliation(s)
- Stefan Krennmair
- Research Fellow, NumBioLab, Department of Orthodontics, Ludwig Maximilian University of Munich, Munich, Germany.
| | - Philipp Winterhalder
- Resident, Department of Oral Maxillofacial Surgery, RWTH Aachen University, Aachen, Germany
| | - Stefan Hunger
- Resident, Department of Oral Maxillofacial Surgery, Johannes Kepler University Linz, Linz, Austria
| | - Stefan Rupperti
- Research Fellow, NumBioLab, Department of Orthodontics, Ludwig Maximilian University of Munich, Munich, Germany
| | - Christof Holberg
- Professor, Head of NumBioLab, Department of Orthodontics, Ludwig Maximilian University of Munich, Munich, Germany
| |
Collapse
|
50
|
Ohyama T, Nakabayashi S, Yasuda H, Kase T, Namaki S. Mechanical analysis of the effects of implant position and abutment height on implant-assisted removable partial dentures. J Prosthodont Res 2019; 64:340-345. [PMID: 31662242 DOI: 10.1016/j.jpor.2019.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/18/2019] [Accepted: 09/25/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE An increasing number of clinical reports describe the use of dental implants as abutments in implant-assisted removable partial dentures (IARPD). We used three-dimensional finite element analysis to evaluate IARPD as a unilateral mandibular distal extension denture. Specifically, the mechanical effects of implant position and abutment height on the abutment tooth, denture, and denture-supporting tissue were assessed. METHODS The models analyzed were defects of the left mandibular second premolar and first and second molars prosthetically treated with an IARPD using one implant for each tooth position. There were two abutment heights: one equal to that of the mucosa and another that was elevated 2 mm above the mucosa. Six models were constructed. RESULTS For mucosal-level abutments, movement of the abutment tooth was lower for implants positioned distal to the abutment tooth than for those positioned medial to the abutment tooth. For elevated abutments, movement of the abutment tooth was lower for implants positioned medial to the abutment tooth than for those positioned distal to the abutment tooth. CONCLUSIONS The mechanical effects on abutment teeth at the same implant position differed in relation to implant abutment height.
Collapse
Affiliation(s)
- Tetsuo Ohyama
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
| | - Shinya Nakabayashi
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Hiroyasu Yasuda
- Department of Partial Denture Prosthodontics, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Takeshi Kase
- Division of Applied Oral Sciences, Nihon University Graduate School of Dentistry, Tokyo, Japan
| | - Shunsuke Namaki
- Department of Clinical Medicine, Nihon University School of Dentistry, Tokyo, Japan
| |
Collapse
|