1
|
Fan X, Chen L, Chen Q, Wang F, Wu Y, Sun Y. Influence of a mesial cantilever on stress, strain, and axial force in fixed partial dentures with a distally tilted implant in the atrophic posterior maxilla. J Prosthodont Res 2024:JPR_D_23_00218. [PMID: 38616127 DOI: 10.2186/jpr.jpr_d_23_00218] [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: 04/16/2024]
Abstract
PURPOSE This study aimed to investigate whether the presence of a mesial cantilever influences the biomechanical behavior and screw loosening in fixed partial dentures (FPDs) with a distally tilted implant in the atrophic posterior maxilla and where to best place the distal implant. METHODS Two configurations of implant-supported four-unit FPDs were modelled using finite element analysis. Five interabutment distances were considered. The stress and strain distributions in the implants, abutments, and prosthetic screws were verified under occlusal loading. The development of the axial force on the abutments and screws was also examined. Two-sample t-tests were used to identify differences (P < 0.05). RESULTS The von Mises stress distributions of the components in the two configurations were similar, as were the maximum plastic strains of the distal prosthetic screws, distal implants, and 30° abutments. The difference in the maximum plastic strains of the straight abutments was statistically significant. The preload of the 30° abutment screws was significantly reduced after the initial loading. In the absence of a mesial cantilever, the axial force on the straight abutments increased. However, when a mesial cantilever was used, the preload of the straight abutments was maintained, and the axial force on the prosthetic screws fluctuated less. The axial force fluctuation of the abutments gradually decreased as the interabutment distance increased. CONCLUSIONS Mesial cantilever usage had minimal effect on stress or strain distribution in FPD implants, abutments, or prostheses. However, it helped resist screw loosening. The distal screw access hole was preferably positioned close to the prosthetic end.
Collapse
Affiliation(s)
- Xiaohui Fan
- Shanghai Key Laboratory of Advanced High Temperature Materials and Precision Forming, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Li Chen
- Yangtze Delta Advanced Material Research Institute, Suzhou, China
| | - Qiuren Chen
- Yangtze Delta Advanced Material Research Institute, Suzhou, China
| | - Feng Wang
- Department of Second Dental Center, Shanghai Ninth People's Hospital, School of Medicine; College of Stomatology, Shanghai Jiao Tong University; National Center for Stomatology; National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yiqun Wu
- Department of Second Dental Center, Shanghai Ninth People's Hospital, School of Medicine; College of Stomatology, Shanghai Jiao Tong University; National Center for Stomatology; National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yuanyuan Sun
- Department of Second Dental Center, Shanghai Ninth People's Hospital, School of Medicine; College of Stomatology, Shanghai Jiao Tong University; National Center for Stomatology; National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, China
- Department of Oral Cell Biology, Academic Center for Dentistry Amsterdam (ACTA), Vrije Universiteit Amsterdam and University of Amsterdam, Amsterdam, Netherlands
| |
Collapse
|
2
|
Alaña M, Lopez-Arancibia A, Ghouse S, Rodriguez-Florez N, Ruiz de Galarreta S. Additively manufactured lattice structures with controlled transverse isotropy for orthopedic porous implants. Comput Biol Med 2022; 150:105761. [PMID: 36126355 DOI: 10.1016/j.compbiomed.2022.105761] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/31/2022] [Accepted: 06/18/2022] [Indexed: 11/26/2022]
Abstract
Additively manufactured lattice structures enable the design of tissue scaffolds with tailored mechanical properties, which can be implemented in porous biomaterials. The adaptation of bone to physiological loads results in anisotropic bone tissue properties which are optimized for site-specific loads; therefore, some bone sites are stiffer and stronger along the principal load direction compared to other orientations. In this work, a semi-analytical model was developed for the design of transversely isotropic lattice structures that can mimic the anisotropy characteristics of different types of bone tissue. Several design possibilities were explored, and a particular unit cell, which was best suited for additive manufacturing was further analyzed. The design of the unit cell was parameterized and in-silico analysis was performed via Finite Element Analysis. The structures were manufactured additively in metal and tested under compressive loads in different orientations. Finite element analysis showed good correlation with the semi-analytical model, especially for elastic constants with low relative densities. The anisotropy measured experimentally showed a variable accuracy, highlighting the deviations from designs to additively manufactured parts. Overall, the proposed model enables to exploit the anisotropy of lattice structures to design lighter scaffolds with higher porosity and increased permeability by aligning the scaffold with the principal direction of the load.
Collapse
Affiliation(s)
- Markel Alaña
- Department of Mechanical Engineering and Materials, Universidad de Navarra, TECNUN Escuela de Ingenieros, Paseo Manuel de Lardizabal, 13, 20018 San Sebastian, Spain.
| | - Aitziber Lopez-Arancibia
- Department of Mechanical Engineering and Materials, Universidad de Navarra, TECNUN Escuela de Ingenieros, Paseo Manuel de Lardizabal, 13, 20018 San Sebastian, Spain
| | - Shaaz Ghouse
- Department of Mechanical Engineering, Imperial College London, South Kensington London SW7 2AZ, UK
| | - Naiara Rodriguez-Florez
- Department of Mechanical Engineering and Materials, Universidad de Navarra, TECNUN Escuela de Ingenieros, Paseo Manuel de Lardizabal, 13, 20018 San Sebastian, Spain; IKERBASQUE, Basque Foundation for Science, Plaza Euskadi 5, 48009, Bilbao, Spain
| | - Sergio Ruiz de Galarreta
- Department of Mechanical Engineering and Materials, Universidad de Navarra, TECNUN Escuela de Ingenieros, Paseo Manuel de Lardizabal, 13, 20018 San Sebastian, Spain
| |
Collapse
|
3
|
Mourad KE, Altonbary GY, Emera RMK, Hegazy SAF. Polyetheretherketone CAD-CAM framework for all-on-4 mandibular full arch prosthesis: Three years' retrospective study of periimplant soft tissue changes and ridge base relationship. J Prosthodont 2022. [PMID: 36069047 DOI: 10.1111/jopr.13602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/27/2022] [Indexed: 11/30/2022] Open
Abstract
PURPOSE This study was conducted to evaluate the clinical peri-implant soft tissue changes during first year after occlusal loading and the ridge base relation after three years for mandibular CAD-CAM manufactured screw-retained implant-supported hybrid prosthesis of polyetheretherketone (PEEK) framework utilized with All-on-Four treatment concept. MATERIAL AND METHODS Sixteen completely edentulous patients were rehabilitated by 4 implants following the All-On-Four protocol. After 3 months, the definitive prosthesis was constructed to be a screw retained CAD-CAM milled framework from the modified PEEK (BioHPP), bonded to polymethylmethacrylate (PMMA) teeth and a pink shaded indirect light-polymerized nanofilled composite resin imitating the soft tissues. Peri-implant soft tissue changes regarding plaque, bleeding, gingival scores, and probing depth were evaluated at prosthesis insertion (T0), six months (T1) and 12 months (T2) after insertion. Also, monitoring of the ridge base relation was performed using cone beam computed tomography after one year (T0), two years (T1), and three years (T2) after mandibular fixed detachable All-on-Four framework insertion. Using Shapiro Wilk tests using SPSS® software version 22 (SPSS Inc.), all clinical data were non- parametric while the ridge base relation data was parametric. RESULTS There were statistically significant differences regarding plaque, gingival, and bleeding scores for all implants with advancement of time. However, there was a statistically insignificant difference regarding probing depth in the posterior implants (p = .581). Regarding ridge base relation, there was a significant difference between observation times only in the anterior ridge area in between the two anterior implants (p = .011). CONCLUSION Within limitations of the study, the full arch PEEK framework of fixed-detachable, hybrid prosthesis used with All-on-Four concept for rehabilitation of mandibular edentulous arches is an acceptable treatment approach. Based on the stable ridge base relation posteriorly found in this study, less stress is distributed to the underlining bone due to the shock absorbing ability of PEEK. Special considerations for frequent soft tissue follow up and regular maintenance of oral hygiene measures are recommended. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Khloud E Mourad
- Department of Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Gilan Y Altonbary
- Department of Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Radwa M K Emera
- Department of Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Salah A F Hegazy
- Department of Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| |
Collapse
|
4
|
The Effect of Abutment Angulation and Crown Material Compositions on Stress Distribution in 3-Unit Fixed Implant-Supported Prostheses: A Finite Element Analysis. Int J Dent 2022; 2022:4451810. [PMID: 36065400 PMCID: PMC9440824 DOI: 10.1155/2022/4451810] [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: 05/13/2022] [Accepted: 07/04/2022] [Indexed: 12/05/2022] Open
Abstract
Objective The aim of this study was to evaluate influence of abutment angulation and restoration material compositions on the stress pattern in dental implants and their surrounding bone. Materials and Methods In this finite element study, the six different solid 3D models of “mandibular 3-unit fixed implant-supported prostheses” were analyzed. In all of these models, a straight abutment was used for anterior implants at the second premolar site, and in order to posterior implant at the second molar site, abutments with three different angles (straight, 15, and 20°) were used. Also, two different restoration material compositions (porcelain fused to base metal (PFBM) and porcelain fused to noble metal (PFNM)) were considered for fixed implant supported restorations. A 450 N static force was exerted in a straight manner along the longitudinal axis of the anterior implant in a tripod, and the stress distribution was measured based on the restoration materials and abutment angulations of the models in the 3 sites of cortical, cancellous bone, and fixtures. The simulation was performed with ABAQUS 6.13 Software. Results In all models, stress values in surrounding cortical bone were more than in spongy bone. Maximum stress levels in an anterior abutment-implant complex were seen in models with angled implants. In models with parallel implants, the stress level of a molar straight abutment-implant complex was less than that of premolar straight ones. In an angled posterior abutment-implant complex, less stress level was detected compared to straight ones. In all PFNB models, stress values were slightly more and distributed in a wider area of premolar straight abutments. Conclusion Increasing an abutment angle, increases stress in surrounding bone and straight implant-abutment combination. It seems that the crown material composition affects stress distribution of the implant-abutment combination but does not affect stress distribution of surrounding bone.
Collapse
|
5
|
Hu L, Sa Y. A digital technique to manage restoration of severely tilted adjacent implants: A dental technique. J Prosthodont 2022; 31:447-451. [PMID: 35340075 DOI: 10.1111/jopr.13509] [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: 12/10/2021] [Accepted: 03/21/2022] [Indexed: 11/29/2022] Open
Abstract
Implant placement in close proximity with adverse angulations may result in difficulty with impression making. With the lock surface function provided by intraoral scanning software programs, the severely tilted adjacent implants can be digitized one by one without interfering with the accuracy of digital cast. This article presents a straightforward digital impression technique for severely mesiodistally tilted adjacent implants in a clinical case. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Liqun Hu
- Graduate student, Department of Prosthodontics, The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, PR China
| | - Yue Sa
- Associate professor, Department of Prosthodontics, The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, PR China
| |
Collapse
|
6
|
Evaluation of Stress Distribution during Insertion of Tapered Dental Implants in Various Osteotomy Techniques: Three-Dimensional Finite Element Study. MATERIALS 2021; 14:ma14247547. [PMID: 34947142 PMCID: PMC8704667 DOI: 10.3390/ma14247547] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/27/2021] [Accepted: 11/28/2021] [Indexed: 11/17/2022]
Abstract
Conventional osteotomy techniques can, in some cases, induce higher stress on bone during implant insertion as a result of higher torque. The aim of the present study was to evaluate and compare the stress exerted on the underlying osseous tissues during the insertion of a tapered implant using different osteotomy techniques through a dynamic finite element analysis which has been widely applied to study biomedical problems through computer-aided software. In three different types of osteotomy techniques, namely conventional (B1), bone tap (B2), and countersink (B3), five models and implants designed per technique were prepared, implant insertion was simulated, and stress exerted by the implant during each was evaluated. Comparison of stress scores on the cortical and cancellous bone at different time points and time intervals from initiation of insertion to the final placement of the implant was made. There was a highly statistically significant difference between B1 and B2 (p = 0.0001) and B2 and B3 (p = 0.0001) groups. In contrast, there was no statistically significant difference in the stress scores between B1 and B3 (p = 0.3080) groups at all time points of implant placement. Overall, a highly significant difference was observed between the stresses exerted in each technique. Within the limitations of our study, bone tap significantly exerted lesser stresses on the entire bone than conventional and countersink type of osteotomy procedures. Considering the stress distribution at the crestal region, the countersink showed lower values in comparison to others.
Collapse
|
7
|
Haroun F, Ozan O. Evaluation of Stresses on Implant, Bone, and Restorative Materials Caused by Different Opposing Arch Materials in Hybrid Prosthetic Restorations Using the All-on-4 Technique. MATERIALS 2021; 14:ma14154308. [PMID: 34361502 PMCID: PMC8348490 DOI: 10.3390/ma14154308] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/17/2021] [Accepted: 07/28/2021] [Indexed: 12/17/2022]
Abstract
The long-term success of dental implants is greatly influenced by the use of appropriate materials while applying the “All-on-4” concept in the edentulous jaw. This study aims to evaluate the stress distribution in the “All-on-4” prosthesis across different material combinations using three-dimensional finite element analysis (FEA) and to evaluate which opposing arch material has destructive effects on which prosthetic material while offering certain recommendations to clinicians accordingly. Acrylic and ceramic-based hybrid prosthesis have been modelled on a rehabilitated maxilla using the “All-on-4” protocol. Using different materials and different supports in the opposing arch (natural tooth, and implant/ceramic, and acrylic), a multi-vectorial load has been applied. To measure stresses in bone, maximum and minimum principal stress values were calculated, while Von Mises stress values were obtained for prosthetic materials. Within a single group, the use of an acrylic implant-supported prosthesis as an antagonist to a full arch implant-supported prosthesis yielded lower maximum (Pmax) and minimum (Pmin) principal stresses in cortical bone. Between different groups, maxillary prosthesis with polyetheretherketone as framework material showed the lowest stress values among other maxillary prostheses. The use of rigid materials with higher moduli of elasticity may transfer higher stresses to the peri implant bone. Thus, the use of more flexible materials such as acrylic and polyetheretherketone could result in lower stresses, especially upon atrophic bones.
Collapse
Affiliation(s)
- Feras Haroun
- Correspondence: ; Tel.: +90-548-828-66-79 or +90-542-888-99-90 or +965-97170419
| | | |
Collapse
|
8
|
Ramlee MH, Gan HS, Daud SA, Abdul Wahab A, Abdul Kadir MR. Stress Distributions and Micromovement of Fragment Bone of Pilon Fracture Treated With External Fixator: A Finite Element Analysis. J Foot Ankle Surg 2021; 59:664-672. [PMID: 32600559 DOI: 10.1053/j.jfas.2019.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 05/29/2019] [Accepted: 09/01/2019] [Indexed: 02/03/2023]
Abstract
Osteoporosis and osteoarthritis are common pathological problems of the human bone tissue. There are some cases of pilon fractures associated with these 2 pathological conditions. In terms of treatment, for a normal and healthy bone with pilon fracture, the use of the Delta external fixator is a favorable option because it can allow early mobilization for patients and provide stability for the healing process. However, the stability of the external fixator differs when there is low bone stiffness, which has not been previously investigated. Therefore, this study was conducted to determine the stability of the external fixator to treat pilon fracture associated with osteoporosis and osteoarthritis, particularly to differentiate the stress distribution and micromovement of fracture fragment. Three-dimensional finite element models of the ankle and foot bones were reconstructed based on the computed tomography datasets. The bones consisted of 5 metatarsal, 3 cuneiform, and 1 each of cuboid, navicular, calcaneus, talus, fibula, and tibia bones. They were assigned with linear isotropic behavior. The ankle joint consisted of ligament and cartilage, and they were assigned with the use of linear links and the Mooney-Rivlin model, respectively. During simulation of the gait cycle, 70 N and 350 N were applied axially to the tibia bone to represent the swing and stance phases, respectively. The metatarsal and calcaneus bones were fixed to prevent any movement of the rigid body. The study found that the greatest von Mises stress value was observed at the pin-bone interface for the osteoporosis (108 MPa) model, followed by the osteoarthritis (87 MPa) and normal (44 MPa) models, during the stance phase. For micromovement, the osteoporosis model had the largest value at 0.26 mm, followed by the osteoarthritis (0.09 mm) and normal (0.03 mm) models. In conclusion, the greatest magnitudes of stress and micromovement were observed for the osteoporosis bone and extra care should be taken to treat pilon fracture associated with this pathological condition.
Collapse
Affiliation(s)
- Muhammad Hanif Ramlee
- Deputy Director, Medical Devices and Technology Centre (MEDITEC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, Johor, Malaysia.
| | - Hong Seng Gan
- Senior Lecturer, British Malaysian Institute, Universiti Kuala Lumpur, Gombak, Selangor
| | - Siti Asmah Daud
- Senior Lecturer, Centre for Intelligent Signal & Imaging Research (CISIR), Electric and Electronics Engineering Department, Faculty of Engineering, Universiti Teknologi PETRONAS, Perak, Malaysia
| | - Asnida Abdul Wahab
- Senior Lecturer, School of Biomedical Engineering and Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, Johor, Malaysia
| | - Mohammed Rafiq Abdul Kadir
- Professor, Sports Innovation and Technology Centre (SITC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, Johor, Malaysia
| |
Collapse
|
9
|
Dayan SC, Geckili O. The influence of framework material on stress distribution in maxillary complete-arch fixed prostheses supported by four dental implants: a three-dimensional finite element analysis. Comput Methods Biomech Biomed Engin 2021; 24:1606-1617. [PMID: 33798003 DOI: 10.1080/10255842.2021.1903450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The purpose of the present study was to compare the stress distribution patterns of four materials used for the framework of All-on-4 prostheses. Following framework materials were evaluated: PEKK, PEEK, titanium, and monolithic zirconia. Bilateral 150 N axial and oblique loads were applied in the first molar region and analyzed using FEA. The highest maximum principal stress and minimum principal stress values in cortical bone were found to appear with PEKK and PEEK frameworks around the posterior dental implants upon oblique loading. The fabrication of frameworks from rigid materials in All-on-4 prostheses reduces stress in dental implants and peri-implant bone when the distal implants are tilted 30°.
Collapse
Affiliation(s)
| | - Onur Geckili
- Department of Prosthodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey
| |
Collapse
|
10
|
Biomechanical comparison of the All-on-4, M-4, and V-4 techniques in an atrophic maxilla: A 3D finite element analysis. Comput Biol Med 2020; 123:103880. [PMID: 32768041 DOI: 10.1016/j.compbiomed.2020.103880] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/16/2020] [Accepted: 06/21/2020] [Indexed: 11/21/2022]
Abstract
BACKGROUND Patients with severely atrophied jaws can be challenging in implantology. The All-on-4 treatment concept eliminates advanced augmentation procedures in highly resorbed ridges by preserving the relevant anatomic structures. In addition, the inclination of the distal implants enables the placement of longer implants. Hence, tilting the anterior implants allows longer implant placement, in line with the distal implants of the All-on-4 concept. This study compared the biomechanical aspects of the standard All-on-4 treatment concept with the M-4 and V-4 techniques. METHODS A three-dimensional model of an edentulous maxilla was created to perform three-dimensional finite element analysis. Three different configurations (All-on-4, M-4, and V-4) were modeled by changing the tilt angle of the anterior implants. In each model, to simulate a foodstuff, a solid spherical material was placed on the midline of the incisors and the right first molar region, separately applying an occlusal load of 100 Newtons. The maximum principal stress and minimum principal stress values were acquired for cortical bone, and von Mises stress values were obtained for ductile materials. RESULTS According to the present study's findings, although there were no considerable differences among the models, in general, the All-on-4 group demonstrated slightly higher stresses and the M-4 and V-4 group showed lower stresses. CONCLUSION M-4 or V-4 configurations may be used in cases of severely atrophied anterior maxillae to achieve better primary stabilization.
Collapse
|
11
|
Niroomand MR, Arabbeiki M. Implant stability in different implantation stages: Analysis of various interface conditions. INFORMATICS IN MEDICINE UNLOCKED 2020. [DOI: 10.1016/j.imu.2020.100317] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
12
|
Gümrükçü Z, Kurt S, Köse S. Effect of Root Resection Length and Graft Type Used After Apical Resection: A Finite Element Study. J Oral Maxillofac Surg 2019; 77:1770.e1-1770.e8. [PMID: 31153936 DOI: 10.1016/j.joms.2019.04.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/23/2019] [Accepted: 04/23/2019] [Indexed: 11/18/2022]
Abstract
PURPOSE Apical resection is a surgical technique that involves removing a tooth's root tip and sealing the apical extent of the root canal system. However, evidence-based information on the biomechanical effects of apically resected tooth determinants is lacking. The aim of the present study was to examine the biomechanical effects of using different graft materials and the effect of different resection quantities on the tooth radix. MATERIALS AND METHODS Thirty finite element models of mandibular central incisors with 1-cm defects in their apical regions were constructed using SolidWorks software (SolidWorks, Waltham, MA). Resections of 0, 1, 2, 3, 4, and 5 mm were created at the root tips, and tissue regeneration was simulated in the empty cavity models using the material properties of healed bone, an allograft, a xenograft, and hydroxyapatite to the grafts used to fill the apical sites. A 100-N force was applied to the various groups of teeth in the oblique (45°) direction, and the maximal von Mises stress and displacement values were determined using Ansys, version 16, software (ANSYS, Inc, Canonsburg, PA). RESULTS The highest of these values was observed in the 5-mm resected and empty model. Increasing the resection amount caused the stress and displacement to increase. The lowest stress and deformation values were seen in the hydroxyapatite group, followed by the xenograft group and the allograft group. CONCLUSIONS The results of the present study have shown that grafting into the apical defect provides biomechanical support for resection of the root structure.
Collapse
Affiliation(s)
- Zeynep Gümrükçü
- Assistant Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Recep Tayyip Erdoğan University, Rize, Turkey.
| | - Sevda Kurt
- Assistant Professor, Department of Periodontology, Faculty of Dentistry, Recep Tayyip Erdoğan University, Rize, Turkey
| | - Sinan Köse
- Trabzon Chamber of Commerce and Industry, Trabzon, Turkey
| |
Collapse
|
13
|
Influence of implant number, length, and tilting degree on stress distribution in atrophic maxilla: a finite element study. Med Biol Eng Comput 2017; 56:979-989. [PMID: 29119541 DOI: 10.1007/s11517-017-1737-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 10/04/2017] [Indexed: 10/18/2022]
Abstract
This study aims to evaluate the stress values, created in peri-implant region as a consequence of loading on fixed hybrid dentures that was planned with different implant numbers, lengths, or tilting angulations. Thirteen three-dimensional (3D) finite element analysis models were generated with four, five, or seven implants (group A, B, and C). Except the distal implants, all implants were modeled at 4.1 mm (diameter) and 11.5 mm (length) in size. Distal implants were configured to be in five different lengths (6, 8, 11.5, 13, and 16 mm) and three different implant inclination degrees (0°, 30°, and 45°). A 150-N load was applied vertically on prosthesis. Released stresses were evaluated comparatively. The lowest von Mises stress values were found in group C, in the 11.5-mm implant model. Tilting the distal implants 30° caused higher stress values. In 45°-tilting implant models, lower stress values were recorded according to the 30°-tilting models. The ideal implant number is seven for an edentulous maxilla. Tilting the implants causes higher stress values. A 45° inclination of implant causes lower stress values according to the 30° models due to a shorter cantilever. The ideal implant length is 11.5 mm.
Collapse
|