1
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Ryan LL, Kohles SS. A temporospatial histomorphometric analysis of bone density adjacent to acid-etched self-tapping dental implants with an external hexagon connection in the female baboon. Clin Oral Investig 2022; 26:2143-2154. [PMID: 34585261 DOI: 10.1007/s00784-021-04195-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/21/2021] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To characterize osseointegration as the percent of bone-implant contact (%BIC) along the surface (0.0 mm) as well as at surface profiles 0.5 mm and 1.0 mm lateral to the implant, determining any differences between early occlusally loaded and non-loaded implants. MATERIAL AND METHODS In ten adult female baboons, 120 dental implants were randomly placed in opposing mandibular and maxillary locations. Eighty sites had two groups of healing (no load) of either 1 (n = 40) or 2 (n = 40) months leading to 3 months of functional loading. These sites received full acid-etched surface implants. The 40 control implants represented healing only periods (no load) for 1 (n = 10), 2 (n = 10), 4 (n = 10), and 5 (n = 10) months. These implants were of a vertically split surface texture design (acid-etched and machined). Block sections and photomicrographs were obtained. Blinded histometric analyses determined the %BIC via a superimposed template. RESULTS The unloaded groups (1, 2, and 4 months) had higher %BIC compared to the 5-month group (p < 0.0001). The loaded groups exhibited mean bone densities of 59.2% and 55.5% (1-month healing at 0.5 mm and 1.0 mm, respectively) and 61.0% and 57.1% (2-month healing at 0.5 mm and 1.0 mm, respectively) with no significant difference between healing time (p = 0.4118). CONCLUSION There was a lateral increase in %BIC in the loaded compared to unloaded groups. CLINICAL RELEVANCE The decrease in bone densities at the 5-month unloaded group suggests that there is a critical earlier time period when dental implants should be placed into functional load.
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Affiliation(s)
- Lara L Ryan
- Johnson County Periodontics, Dental Implants, and Laser Surgery, Overland Park, KS, USA
| | - Sean S Kohles
- Kohles Bioengineering, 1731 SE 37th Avenue, Portland, OR, 97214-5135, USA.
- Division of Biomaterials & Biomechanics, School of Dentistry, and Department of Emergency Medicine, School of Medicine, Oregon Health & Science University, Portland, OR, USA.
- Department of Human Physiology, University of Oregon, Eugene, OR, USA.
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2
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Xie J, Rittel D, Shemtov-Yona K, Shah FA, Palmquist A. A stochastic micro to macro mechanical model for the evolution of bone-implant interface stiffness. Acta Biomater 2021; 131:415-423. [PMID: 34129958 DOI: 10.1016/j.actbio.2021.06.019] [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] [Received: 12/03/2020] [Revised: 06/05/2021] [Accepted: 06/09/2021] [Indexed: 01/05/2023]
Abstract
Upon placement of an implant into living bone, an interface is formed through which various biochemical, biological, physical, and mechanical interactions take place. This interface evolves over time as the mechanical properties of peri-implant bone increase. Owing to the multifactorial nature of interfacial processes, it is challenging to devise a comprehensive model for predicting the mechanical behavior of the bone-implant interface. We propose a simple spatio-temporally evolving mechanical model - from an elementary unit cell comprising randomly oriented mineralized collagen fibrils having randomly assigned stiffness all the way up to a macroscopic bone-implant interface in a gap healing scenario. Each unit cell has an assigned Young's modulus value between 1.62 GPa and 25.73 GPa corresponding to minimum (i.e., 0) and maximum (i.e., 0.4) limits of mineral volume fraction, respectively, in the overlap region of the mineralized collagen fibril. Gap closure and subsequent stiffening are modeled to reflect the two main directions of peri-implant bone formation, i.e., contact osteogenesis and distance osteogenesis. The linear elastic stochastic finite element model reveals highly nonlinear temporal evolution of bone-implant interface stiffness, strongly dictated by the specific kinetics of contact osteogenesis and distance osteogenesis. The bone-implant interface possesses a small stiffness until gap closure, which subsequently evolves into a much higher stiffness, and this transition is reminiscent of a percolation transition whose threshold corresponds to gap closure. The model presented here, albeit preliminary, can be incorporated into future calculations of the bone-implant system where the interface is well-defined mechanically. STATEMENT OF SIGNIFICANCE: A simple, physically informed model for the mechanical characteristics of the bone-implant interface is still missing. Here, we start by extending the reported mechanical characteristics of a one cubic micrometre unit cell to a 250 µm long interface made of 1 µm thick layers. The stiffness of each cell (based on mineral content) is assigned randomly to mimic bone micro-heterogeneity. The numerical study of this interface representative structure allows for the simultaneous determination of the spatio-temporal evolution of the mechanical response at local (discrete element) and global (overall model) scales. The proposed model is the first of this kind that can easily be incorporated into realistic future models of bone-implant interaction with emphasis on implant stability and different loading conditions.
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Ding SJ, Chu YH, Chen PT. Mechanical Biocompatibility, Osteogenic Activity, and Antibacterial Efficacy of Calcium Silicate-Zirconia Biocomposites. ACS OMEGA 2021; 6:7106-7118. [PMID: 33748624 PMCID: PMC7970563 DOI: 10.1021/acsomega.1c00097] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
Zirconia ceramics with high mechanical properties have been used as a load-bearing implant in the dental and orthopedic surgery. However, poor bone bonding properties and high elastic modulus remain a challenge. Calcium silicate (CaSi)-based ceramic can foster osteoblast adhesion, growth, and differentiation and facilitate bone ingrowth. This study was to prepare CaSi-ZrO2 composites and evaluate their mechanical properties, long-term stability, in vitro osteogenic activity, and antibacterial ability. The Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria and human mesenchymal stem cells (hMSCs) were used to evaluate the antibacterial and osteogenic activities of implants in vitro, respectively. Results indicated that the three-point bending strength of ZrO2 was 486 MPa and Young's modulus was 128 GPa, which were much higher than those of the cortical bone. In contrast, the bending strength and modulus of 20% (201 MPa and 48 GPa, respectively) and 30% CaSi (126 MPa and 20 GPa, respectively) composites were close to the reported strength and modulus of the cortical bone. As expected, higher CaSi content implants significantly enhanced cell growth, differentiation, and mineralization of hMSCs. It is interesting to note the induction ability of CaSi in osteogenic differentiation of hMSCs even when cultured in the absence of an osteogenic differentiation medium. The composite with the higher CaSi contents exhibited the greater bacteriostatic effect against E. coli and S. aureus. In conclusion, the addition of 20 wt % CaSi can effectively improve the mechanical biocompatibility, osteogenesis, and antibacterial activity of ZrO2 ceramics, which may be a potential choice for load-bearing applications.
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Affiliation(s)
- Shinn-Jyh Ding
- Institute
of Oral Science, Chung Shan Medical University, Taichung 402, Taiwan
- Department
of Stomatology, Chung Shan Medical University
Hospital, Taichung 402, Taiwan
| | - Ying-Hung Chu
- Institute
of Oral Science, Chung Shan Medical University, Taichung 402, Taiwan
| | - Pei-Tung Chen
- Institute
of Oral Science, Chung Shan Medical University, Taichung 402, Taiwan
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4
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Fraulob M, Le Cann S, Voumard B, Yasui H, Yano K, Vayron R, Matsukawa M, Zysset P, Haïat G. Multimodal Evaluation of the Spatiotemporal Variations of Periprosthetic Bone Properties. J Biomech Eng 2020; 142:121014. [PMID: 32909597 DOI: 10.1115/1.4048399] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Indexed: 07/25/2024]
Abstract
Titanium implants are widely used in dental and orthopedic surgeries. However, implant failures still occur because of a lack of implant stability. The biomechanical properties of bone tissue located around the implant need to be assessed to better understand the osseointegration phenomena and anticipate implant failure. The aim of this study was to explore the spatiotemporal variation of the microscopic elastic properties of newly formed bone tissue close to an implant. Eight coin-shaped Ti6Al4V implants were inserted into rabbit tibiae for 7 and 13 weeks using an in vivo model allowing the distinction between mature and newly formed bone in a standardized configuration. Nanoindentation and micro-Brillouin scattering measurements were carried out in similar locations to measure the indentation modulus and the wave velocity, from which relative variations of bone mass density were extracted. The indentation modulus, the wave velocity and mass density were found to be higher (1) in newly formed bone tissue located close to the implant surface, compared to mature cortical bone tissue, and (2) after longer healing time, consistently with an increased mineralization. Within the bone chamber, the spatial distribution of elastic properties was more heterogeneous for shorter healing durations. After 7 weeks of healing, bone tissue in the bone chamber close to the implant surface was 12.3% denser than bone tissue further away. Bone tissue close to the chamber edge was 16.8% denser than in its center. These results suggest a bone spreading pathway along tissue maturation, which is confirmed by histology and consistent with contact osteogenesis phenomena.
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Affiliation(s)
- Manon Fraulob
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, Creteil F-94010, France
| | - Sophie Le Cann
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, Creteil F-94010, France
| | - Benjamin Voumard
- ARTORG Centre for Biomedical Engineering Research, University of Bern, Freiburgstrasse 3, Bern CH-3010, Switzerland
| | - Hirokazu Yasui
- Laboratory of Ultrasonic Electronics, Applied Ultrasonic Research Center, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| | - Keita Yano
- Laboratory of Ultrasonic Electronics, Applied Ultrasonic Research Center, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| | - Romain Vayron
- Université Polytechnique Hauts de France, Laboratoire d'Automatique, de Mécanique et d'informatique Industrielles et Humaines, LAMIH UMR CNRS 8201, Valenciennes F-59300, France
| | - Mami Matsukawa
- Laboratory of Ultrasonic Electronics, Applied Ultrasonic Research Center, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
| | - Philippe Zysset
- ARTORG Centre for Biomedical Engineering Research, University of Bern, Freiburgstrasse 3, Bern CH-3010, Switzerland
| | - Guillaume Haïat
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, Creteil F-94010, France
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5
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Le Cann S, Törnquist E, Silva Barreto I, Fraulob M, Albini Lomami H, Verezhak M, Guizar-Sicairos M, Isaksson H, Haïat G. Spatio-temporal evolution of hydroxyapatite crystal thickness at the bone-implant interface. Acta Biomater 2020; 116:391-399. [PMID: 32937205 DOI: 10.1016/j.actbio.2020.09.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/24/2020] [Accepted: 09/09/2020] [Indexed: 02/02/2023]
Abstract
A better understanding of bone nanostructure around the bone-implant interface is essential to improve longevity of clinical implants and decrease failure risks. This study investigates the spatio-temporal evolution of mineral crystal thickness and plate orientation in newly formed bone around the surface of a metallic implant. Standardized coin-shaped titanium implants designed with a bone chamber were inserted into rabbit tibiae for 7 and 13 weeks. Scanning measurements with micro-focused small-angle X-ray scattering (SAXS) were carried out on newly formed bone close to the implant and in control mature cortical bone. Mineral crystals were thinner close to the implant (1.8 ± 0.45 nm at 7 weeks and 2.4 ± 0.57 nm at 13 weeks) than in the control mature bone tissue (2.5 ± 0.21 nm at 7 weeks and 2.8 ± 0.35 nm at 13 weeks), with increasing thickness over healing time (+30 % in 6 weeks). These results are explained by younger bone close to the implant, which matures during osseointegration. Thinner mineral crystals parallel to the implant surface within the first 100 µm indicate that the implant affects the ultrastructure of neighbouring bone , potentially due to heterogeneous interfacial stresses, and suggest a longer maturation process of bone tissue and difficulty in binding to the metal. The bone growth kinetics within the bone chamber was derived from the spatio-temporal evolution of bone tissue's nanostructure, coupled with microtomographic imaging. The findings indicate that understanding mineral crystal thickness or plate orientation can improve our knowledge of osseointegration.
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Affiliation(s)
- Sophie Le Cann
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, F-94010 Creteil, France.
| | - Elin Törnquist
- Department of Biomedical Engineering, Lund University, 221 00 Lund, Sweden
| | | | - Manon Fraulob
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, F-94010 Creteil, France
| | - Hugues Albini Lomami
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, F-94010 Creteil, France
| | - Mariana Verezhak
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen 5232, Switzerland
| | | | - Hanna Isaksson
- Department of Biomedical Engineering, Lund University, 221 00 Lund, Sweden
| | - Guillaume Haïat
- MSME, CNRS UMR 8208, Univ Paris Est Creteil, Univ Gustave Eiffel, F-94010 Creteil, France
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6
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Stocchero M, Jinno Y, Toia M, Jimbo R, Lee C, Yamaguchi S, Imazato S, Becktor JP. In silico multi-scale analysis of remodeling peri-implant cortical bone: a comparison of two types of bone structures following an undersized and non-undersized technique. J Mech Behav Biomed Mater 2020; 103:103598. [DOI: 10.1016/j.jmbbm.2019.103598] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 12/19/2022]
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7
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Gao X, Fraulob M, Haïat G. Biomechanical behaviours of the bone-implant interface: a review. J R Soc Interface 2019; 16:20190259. [PMID: 31362615 PMCID: PMC6685012 DOI: 10.1098/rsif.2019.0259] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/01/2019] [Indexed: 01/09/2023] Open
Abstract
In recent decades, cementless implants have been widely used in clinical practice to replace missing organs, to replace damaged or missing bone tissue or to restore joint functionality. However, there remain risks of failure which may have dramatic consequences. The success of an implant depends on its stability, which is determined by the biomechanical properties of the bone-implant interface (BII). The aim of this review article is to provide more insight on the current state of the art concerning the evolution of the biomechanical properties of the BII as a function of the implant's environment. The main characteristics of the BII and the determinants of implant stability are first introduced. Then, the different mechanical methods that have been employed to derive the macroscopic properties of the BII will be described. The experimental multi-modality approaches used to determine the microscopic biomechanical properties of periprosthetic newly formed bone tissue are also reviewed. Eventually, the influence of the implant's properties, in terms of both surface properties and biomaterials, is investigated. A better understanding of the phenomena occurring at the BII will lead to (i) medical devices that help surgeons to determine an implant's stability and (ii) an improvement in the quality of implants.
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Affiliation(s)
- Xing Gao
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
- Research Centre for Medical Robotics and Minimally Invasive Surgical Devices, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Manon Fraulob
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| | - Guillaume Haïat
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
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8
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Akilbekova D, Ogay V, Yakupov T, Sarsenova M, Umbayev B, Nurakhmetov A, Tazhin K, Yakovlev VV, Utegulov ZN. Brillouin spectroscopy and radiography for assessment of viscoelastic and regenerative properties of mammalian bones. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-11. [PMID: 30264554 PMCID: PMC8357194 DOI: 10.1117/1.jbo.23.9.097004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/15/2018] [Indexed: 05/20/2023]
Abstract
Biomechanical properties of mammalian bones, such as strength, toughness, and plasticity, are essential for understanding how microscopic-scale mechanical features can link to macroscale bones' strength and fracture resistance. We employ Brillouin light scattering (BLS) microspectroscopy for local assessment of elastic properties of bones under compression and the efficacy of the tissue engineering approach based on heparin-conjugated fibrin (HCF) hydrogels, bone morphogenic proteins, and osteogenic stem cells in the regeneration of the bone tissues. BLS is noninvasive and label-free modality for probing viscoelastic properties of tissues that can give information on structure-function properties of normal and pathological tissues. Results showed that MCS and BPMs are critically important for regeneration of elastic and viscous properties, respectively, HCF gels containing combination of all factors had the best effect with complete defect regeneration at week nine after the implantation of bone grafts and that the bones with fully consolidated fractures have higher values of elastic moduli compared with defective bones.
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Affiliation(s)
- Dana Akilbekova
- Nazarbayev University, National Laboratory Astana, Astana, Kazakhstan
- Nazarbayev University, School of Engineering, Department of Chemical Engineering, Astana, Kazakhstan
- Address all correspondence to: Dana Akilbekova, E-mail: ; Zhandos N. Utegulov, E-mail:
| | - Vyacheslav Ogay
- National Center for Biotechnology, Stem Cell Laboratory, Astana, Kazakhstan
| | - Talgat Yakupov
- Nazarbayev University, Department of Physics, School of Science and Technology, Astana, Kazakhstan
| | - Madina Sarsenova
- National Center for Biotechnology, Stem Cell Laboratory, Astana, Kazakhstan
| | - Bauyrzhan Umbayev
- Nazarbayev University, National Laboratory Astana, Astana, Kazakhstan
| | - Asset Nurakhmetov
- Research Institute of Traumatology and Orthopedics, Astana, Kazakhstan
| | - Kairat Tazhin
- Research Institute of Traumatology and Orthopedics, Astana, Kazakhstan
| | - Vladislav V. Yakovlev
- Texas A&M University, Department of Biomedical Engineering and Department of Physics and Astronomy, College Station, Texas, United States
| | - Zhandos N. Utegulov
- Nazarbayev University, Department of Physics, School of Science and Technology, Astana, Kazakhstan
- Address all correspondence to: Dana Akilbekova, E-mail: ; Zhandos N. Utegulov, E-mail:
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9
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Johnson TB, Siderits B, Nye S, Jeong YH, Han SH, Rhyu IC, Han JS, Deguchi T, Beck FM, Kim DG. Effect of guided bone regeneration on bone quality surrounding dental implants. J Biomech 2018; 80:166-170. [PMID: 30170838 DOI: 10.1016/j.jbiomech.2018.08.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 08/13/2018] [Accepted: 08/14/2018] [Indexed: 11/27/2022]
Abstract
Bone quality as well as its quantity at the implant interface is responsible for determining stability of the implant system. The objective of this study is to examine the nanoindentation based elastic modulus (E) at different bone regions adjacent to titanium dental implants with guided bone regeneration (GBR) treated with DBM and BMP-2 during different post-implantation periods. Six adult male beagle dogs were used to create circumferential defects with buccal bone removal at each implantation site of mandibles. The implant systems were randomly assigned to only GBR (control), GBR with demineralized bone matrix (DBM), and GBR with DBM + recombinant human bone morphogenetic protein-2 (rhBMP-2) (BMP) groups. Three animals were sacrificed at each 4 and 8 weeks of post-implantation healing periods. Following buccolingual dissection, the E values were assessed at the defects (Defect), interfacial bone tissue adjacent to the implant (Interface), and pre-existing bone tissue away from the implant (Pre-existing). The E values of BMP group had significantly higher than control and DBM groups for interface and defect regions at 4 weeks of post-implantation period and for the defect region at 8 weeks (p < 0.043). DBM group had higher E values than control group only for the defect region at 4 weeks (p < 0.001). The current results indicate that treatment of rhBMP-2 with GBR accelerates bone tissue mineralization for longer healing period because the GBR likely facilitates a microenvironment to provide more metabolites with open space of the defect region surrounding the implant.
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Affiliation(s)
- Trenton B Johnson
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA
| | - Ben Siderits
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA
| | - Seth Nye
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA
| | - Yong-Hoon Jeong
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA
| | - Seung-Hee Han
- Periodontology, Department of Dental Science, Graduate School, Seoul National University, Seoul, South Korea
| | - In-Chul Rhyu
- Periodontology, Department of Dental Science, Graduate School, Seoul National University, Seoul, South Korea
| | - Jung-Suk Han
- Prosthodontics, Department of Dental Science, Graduate School, Seoul National University, Seoul, South Korea
| | - Toru Deguchi
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA
| | - F Michael Beck
- Division of Oral Bioscience, College of Dentistry, Ohio State University, Columbus, OH, USA
| | - Do-Gyoon Kim
- Division of Orthodontics, College of Dentistry, The Ohio State University, Columbus, OH 43210, USA.
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Yoon HI, Jeon MJ, Kim HL, Kim DG, Han JS. Spatial variation of bone biomechanical properties around a dental implant using nanoindentation: a case study. J Mech Behav Biomed Mater 2018; 79:168-172. [DOI: 10.1016/j.jmbbm.2017.12.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 12/14/2017] [Accepted: 12/27/2017] [Indexed: 10/18/2022]
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11
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Effects on the torsional vibration behavior in the investigation of dental implant osseointegration using resonance frequency analysis: a numerical approach. Med Biol Eng Comput 2017; 55:1649-1658. [DOI: 10.1007/s11517-017-1612-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 01/25/2017] [Indexed: 10/20/2022]
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12
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Shape Optimization of Bone-Bonding Subperiosteal Devices with Finite Element Analysis. BIOMED RESEARCH INTERNATIONAL 2017; 2017:3609062. [PMID: 29392133 PMCID: PMC5748129 DOI: 10.1155/2017/3609062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 11/19/2017] [Indexed: 11/26/2022]
Abstract
Subperiosteal bone-bonding devices have been proposed for less invasive treatments in orthodontics. The device is osseointegrated onto a bone surface without fixation screws and is expected to rapidly attain a bone-bonding strength that successfully meets clinical performance. Hence, the device's optimum shape for rapid and strong bone bonding was examined in this study by finite element analyses. First, a stress analysis was performed for a circular rod device with an orthodontic force parallel to the bone surface, and the estimate of the bone-bonding strength based on the bone fracture criterion was verified with the results of an animal experiment. In total, four cross-sectional rod geometries were investigated: circular (Cr), elliptical (El), semicircular (Sc), and rectangular (Rc). By changing the height of the newly formed bone to mimic the progression of new bone formation, the estimation of the bone-bonding strength was repeated for each geometry. The rod with the Rc cross section exhibited the best performance, followed by those with the Sc, El, and Cr cross sections, from the aspects of the rapid acquisition of strength and the strength itself. Thus, the rectangular cross section is the best for rod-like subperiosteal devices for rapid bone bonding.
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13
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Stress distribution in the transitional peri-implant bone in a single implant-supported prosthesis with platform-switching under different angulated loads. Odontology 2016; 105:68-75. [DOI: 10.1007/s10266-016-0237-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 01/31/2016] [Indexed: 10/22/2022]
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14
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Vayron R, Nguyen VH, Bosc R, Naili S, Haïat G. Assessment of the biomechanical stability of a dental implant with quantitative ultrasound: A three-dimensional finite element study. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2016; 139:773-780. [PMID: 26936559 DOI: 10.1121/1.4941452] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Dental implant stability is an important determinant of the surgical success. Quantitative ultrasound (QUS) techniques can be used to assess such properties using the implant acting as a waveguide. However, the interaction between an ultrasonic wave and the implant remains poorly understood. The aim of this study is to investigate the sensitivity of the ultrasonic response to the quality and quantity of bone tissue in contact with the implant surface. The 10 MHz ultrasonic response of an implant used in clinical practice was simulated using an axisymmetric three-dimensional finite element model, which was validated experimentally. The amplitude of the echographic response of the implant increases when the depth of a liquid layer located at the implant interface increases. The results show the sensitivity of the QUS technique to the amount of bone in contact with the implant. The quality of bone tissue around the implant is varied by modifying the bone biomechanical properties by 20%. The amplitude of the implant echographic response decreases when bone quality increases, which corresponds to bone healing. In all cases, the amplitude of the implant response decreased when the dental implant stability increased, which is consistent with the experimental results.
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Affiliation(s)
- Romain Vayron
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR, 8208 CNRS, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - Vu-Hieu Nguyen
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR, 8208 CNRS, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - Romain Bosc
- Université Paris-Est, INSERM U955, Equipe 10, 8 rue du Général Sarrail, 94010 Créteil Cedex, France
| | - Salah Naili
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR, 8208 CNRS, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - Guillaume Haïat
- CNRS, Laboratoire Modélisation et Simulation Multi-Échelle, MSME UMR 8208 CNRS, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France
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Halldin A, Ander M, Jacobsson M, Hansson S. Simulation of the mechanical interlocking capacity of a rough bone implant surface during healing. Biomed Eng Online 2015; 14:45. [PMID: 25994839 PMCID: PMC4440247 DOI: 10.1186/s12938-015-0038-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 04/16/2015] [Indexed: 11/16/2022] Open
Abstract
Background When an implant is inserted in the bone the healing process starts to osseointegrate the implant by creating new bone that interlocks with the implant. Biomechanical interlocking capacity is commonly evaluated in in vivo experiments. It would be beneficial to find a numerical method to evaluate the interlocking capacity of different surface structures with bone. In the present study, the theoretical interlocking capacity of three different surfaces after different healing times was evaluated by the means of explicit finite element analysis. Methods The surface topographies of the three surfaces were measured with interferometry and were used to construct a 3D bone-implant model. The implant was subjected to a displacement until failure of the bone-to-implant interface and the maximum force represents the interlocking capacity. Results The simulated ratios (test/control) seem to agree with the in vivo ratios of Halldin et al. for longer healing times. However the absolute removal torque values are underestimated and do not reach the biomechanical performance found in the study by Halldin et al. which might be a result of unknown mechanical properties of the interface. Conclusion Finite element analysis is a promising method that might be used prior to an in vivo study to compare the load bearing capacity of the bone-to-implant interface of two surface topographies at longer healing times.
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Affiliation(s)
- Anders Halldin
- Department of Prosthodontics, Faculty of Odontology, Malmö University, 205 06, Malmö, Sweden. .,DENTSPLY Implants, Box 14, 43121, Mölndal, Sweden.
| | - Mats Ander
- Department of Applied Mechanics, Chalmers University of Technology, 41296, Gothenburg, Sweden.
| | - Magnus Jacobsson
- Department of Prosthodontics, Faculty of Odontology, Malmö University, 205 06, Malmö, Sweden.
| | - Stig Hansson
- DENTSPLY Implants, Box 14, 43121, Mölndal, Sweden.
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16
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Finite element simulation of ultrasonic wave propagation in a dental implant for biomechanical stability assessment. Biomech Model Mechanobiol 2015; 14:1021-32. [PMID: 25619479 DOI: 10.1007/s10237-015-0651-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/10/2015] [Indexed: 12/31/2022]
Abstract
Dental implant stability, which is an important parameter for the surgical outcome, can now be assessed using quantitative ultrasound. However, the acoustical propagation in dental implants remains poorly understood. The objective of this numerical study was to understand the propagation phenomena of ultrasonic waves in cylindrically shaped prototype dental implants and to investigate the sensitivity of the ultrasonic response to the surrounding bone quantity and quality. The 10-MHz ultrasonic response of the implant was calculated using an axisymetric 3D finite element model, which was validated by comparison with results obtained experimentally and using a 2D finite difference numerical model. The results show that the implant ultrasonic response changes significantly when a liquid layer is located at the implant interface compared to the case of an interface fully bounded with bone tissue. A dedicated model based on experimental measurements was developed in order to account for the evolution of the bone biomechanical properties at the implant interface. The effect of a gradient of material properties on the implant ultrasonic response is determined. Based on the reproducibility of the measurement, the results indicate that the device should be sensitive to the effects of a healing duration of less than one week. In all cases, the amplitude of the implant response is shown to decrease when the dental implant primary and secondary stability increase, which is consistent with the experimental results. This study paves the way for the development of a quantitative ultrasound method to evaluate dental implant stability.
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Sundaram S, Ramaseshan R, Dash S, Rao SR. Evaluation of the nanostructure of cervical third cementum in health and chronic periodontitis: An in vitro study. J Indian Soc Periodontol 2014; 18:560-6. [PMID: 25425815 PMCID: PMC4239743 DOI: 10.4103/0972-124x.142440] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/10/2014] [Indexed: 12/23/2022] Open
Abstract
Background: During the progression of periodontal disease, the cementum undergoes alterations in its structure and composition. Understanding the nanostructure of cementum, in terms of its mechanical properties, will provide an insight into the milieu that periodontal ligament cells encounter in health and chronic periodontitis. This study aims to analyze the nanomechanical properties of the cervical third of the cementum (transverse section) in health and chronic periodontitis. Materials and Methods: Twenty teeth (10 healthy and 10 periodontally diseased) were collected and the nanomechanical properties of the transverse section of the cervical third cementum were evaluated with depth-sensing nanoindentation technique under dry conditions. A total of 100 nanoindentations were performed to analyze the modulus of elasticity and hardness of cervical third of the cementum. Results: The nanomechanical properties of the healthy cervical third cementum sections were significantly higher (P < 0.05) (hardness: 0.720 ± 0.305 GPa; modulus: 15.420 ± 3.902 GPa) than the diseased cementum section (hardness: 0.422 ± 0.157 GPa; modulus: 11.056 ± 3.434 GPa). Conclusion: The results of our study indicate that the hardness and modulus of elasticity of the cervical third cementum decreases significantly in chronic periodontitis.
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Affiliation(s)
- Subramoniam Sundaram
- Department of Periodontics, Faculty of Dental Sciences, Sri Ramachandra University, Porur, Chennai, India
| | - Rajagopalan Ramaseshan
- Surface and Nanoscience Division, Thin Films and Coatings Section, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - Sitaram Dash
- Surface and Nanoscience Division, Thin Films and Coatings Section, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu, India
| | - Suresh Ranga Rao
- Department of Periodontics, Faculty of Dental Sciences, Sri Ramachandra University, Porur, Chennai, India
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Matsukawa M, Tsubota R, Kawabe M, Fukui K. Application of a micro-Brillouin scattering technique to characterize bone in the GHz range. ULTRASONICS 2014; 54:1155-61. [PMID: 24139301 DOI: 10.1016/j.ultras.2013.09.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Revised: 08/17/2013] [Accepted: 09/01/2013] [Indexed: 05/20/2023]
Abstract
The evaluation of elastic properties of bone matrix has been investigated using several techniques such as nanoindentation and scanning acoustic microscopy (SAM). These techniques make use of good spatial resolution, which can prevent effects due to microstructures at the level of several hundreds of microns. In this paper, micro-Brillouin scattering (μ-BR) is introduced as another possible technique to characterize the elastic properties of bone. This technique is well known as a non-contact and non-destructive method to evaluate viscoelastic properties of transparent materials in the GHz range. Using thin, translucent bone specimens with thicknesses of around 100 μm, and the reflection induced optical geometry, ultrasonic wave velocities in the GHz range were obtained. Because this technique optically measures thermal phonons in the specimen, we can easily measure in-plane anisotropy of wave velocities by rotating the specimen. In a single trabecula, the site matched data between SAM and μ-BR showed good correlation, revealing the applicability of this technique to characterize material properties of bone. Some recent results on the anisotropy in a trabecula and the elasticity evaluation of newly and matured bones are also introduced.
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Affiliation(s)
- Mami Matsukawa
- Laboratory of Ultrasonic Electronics, Doshisha University, 1-3 Tatara-Miyakodani, Kyotanabe, Kyoto 610-0321, Japan.
| | - Ryo Tsubota
- Laboratory of Ultrasonic Electronics, Doshisha University, 1-3 Tatara-Miyakodani, Kyotanabe, Kyoto 610-0321, Japan
| | - Masahiko Kawabe
- Laboratory of Ultrasonic Electronics, Doshisha University, 1-3 Tatara-Miyakodani, Kyotanabe, Kyoto 610-0321, Japan
| | - Kenji Fukui
- Laboratory of Ultrasonic Electronics, Doshisha University, 1-3 Tatara-Miyakodani, Kyotanabe, Kyoto 610-0321, Japan
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Vayron R, Matsukawa M, Tsubota R, Mathieu V, Barthel E, Haiat G. Evolution of bone biomechanical properties at the micrometer scale around titanium implant as a function of healing time. Phys Med Biol 2014; 59:1389-406. [PMID: 24584004 DOI: 10.1088/0031-9155/59/6/1389] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The characterization of the biomechanical properties of newly formed bone tissue around implants is important to understand the osseointegration process. The objective of this study is to investigate the evolution of elastic properties of newly formed bone tissue as a function of healing time. To do so, nanoindentation and micro-Brillouin scattering techniques are coupled following a multimodality approach using histological analysis. Coin-shaped implants were placed in vivo at a distance of 200 µm from the cortical bone surface, leading to an initially empty cavity. Two rabbits were sacrificed after 7 and 13 weeks of healing time. The histological analyses allow us to distinguish mature and newly formed bone tissue. The bone mechanical properties were measured in mature and newly formed bone tissue. Analysis of variance and Tukey-Kramer tests reveals a significant effect of healing time on the indentation modulus and ultrasonic velocities of bone tissue. The results show that bone mass density increases by 12.2% (2.2% respectively) between newly formed bone at 7 weeks (13 weeks respectively) and mature bone. The dependence of bone properties on healing time may be explained by the evolution of bone microstructure and mineralization.
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Affiliation(s)
- Romain Vayron
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR CNRS 8208, 61, avenue du Général de Gaulle, 94010 Créteil, Cedex, France
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Mathieu V, Vayron R, Richard G, Lambert G, Naili S, Meningaud JP, Haiat G. Biomechanical determinants of the stability of dental implants: influence of the bone-implant interface properties. J Biomech 2013; 47:3-13. [PMID: 24268798 DOI: 10.1016/j.jbiomech.2013.09.021] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 09/18/2013] [Accepted: 09/24/2013] [Indexed: 12/19/2022]
Abstract
Dental implants are now widely used for the replacement of missing teeth in fully or partially edentulous patients and for cranial reconstructions. However, risks of failure, which may have dramatic consequences, are still experienced and remain difficult to anticipate. The stability of biomaterials inserted in bone tissue depends on multiscale phenomena of biomechanical (bone-implant interlocking) and of biological (mechanotransduction) natures. The objective of this review is to provide an overview of the biomechanical behavior of the bone-dental implant interface as a function of its environment by considering in silico, ex vivo and in vivo studies including animal models as well as clinical studies. The biomechanical determinants of osseointegration phenomena are related to bone remodeling in the vicinity of the implants (adaptation of the bone structure to accommodate the presence of a biomaterial). Aspects related to the description of the interface and to its space-time multiscale nature will first be reviewed. Then, the various approaches used in the literature to measure implant stability and the bone-implant interface properties in vitro and in vivo will be described. Quantitative ultrasound methods are promising because they are cheap, non invasive and because of their lower spatial resolution around the implant compared to other biomechanical approaches.
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Affiliation(s)
- Vincent Mathieu
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| | - Romain Vayron
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| | - Gilles Richard
- Septodont, 58 Rue Pont de Créteil, 94100 Saint-Maur-des-Fossés, France
| | - Grégory Lambert
- Septodont, 58 Rue Pont de Créteil, 94100 Saint-Maur-des-Fossés, France
| | - Salah Naili
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| | - Jean-Paul Meningaud
- Service de Chirurgie Plastique, Reconstructrice et Esthétique, CHU H. Mondor, 94017 Créteil cedex, France
| | - Guillaume Haiat
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France.
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21
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Karunratanakul K, Kerckhofs G, Lammens J, Vanlauwe J, Schrooten J, Van Oosterwyck H. Validation of a finite element model of a unilateral external fixator in a rabbit tibia defect model. Med Eng Phys 2013; 35:1037-43. [DOI: 10.1016/j.medengphy.2012.10.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 09/28/2012] [Accepted: 10/05/2012] [Indexed: 11/25/2022]
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22
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Zhang Y, Wang J, Wang P, Fan X, Li X, Fu J, Li S, Fan H, Guo Z. Low elastic modulus contributes to the osteointegration of titanium alloy plug. J Biomed Mater Res B Appl Biomater 2012; 101:584-90. [DOI: 10.1002/jbm.b.32860] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 10/07/2012] [Accepted: 11/11/2012] [Indexed: 11/11/2022]
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23
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Vayron R, Barthel E, Mathieu V, Soffer E, Anagnostou F, Haiat G. Nanoindentation measurements of biomechanical properties in mature and newly formed bone tissue surrounding an implant. J Biomech Eng 2012; 134:021007. [PMID: 22482674 DOI: 10.1115/1.4005981] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The characterization of the biomechanical properties of newly formed bone tissue around implants is important to understand the osseointegration process. The objective of this study is to investigate the evolution of the hardness and indentation modulus of newly formed bone tissue as a function of healing time. To do so, a nanoindentation device is employed following a multimodality approach using histological analysis. Coin-shaped implants were placed in vivo at a distance of 200 μm from the cortical bone surface, leading to an initially empty cavity of 200 μm * 4.4 mm. Three New Zealand White rabbits were sacrificed after 4, 7, and 13 weeks of healing time. The bone samples were embedded and analyzed using histological analyses, allowing to distinguish mature and newly formed bone tissue. The bone mechanical properties were then measured in mature and newly formed bone tissue. The results are within the range of hardness and apparent Young's modulus values reported in previous literature. One-way ANOVA test revealed a significant effect of healing time on the indentation modulus (p < 0.001, F = 111.24) and hardness (p < 0.02, F = 3.47) of bone tissue. A Tukey-Kramer analysis revealed that the biomechanical properties of newly formed bone tissue (4 weeks) were significantly different from those of mature bone tissue. The comparison with the results obtained in Mathieu et al. (2011, "Micro-Brillouin Scattering Measurements in Mature and Newly Formed Bone Tissue Surrounding an Implant," J. Biomech. Eng., 133, 021006). shows that bone mass density increases by approximately 13.5% between newly formed bone (7 weeks) and mature bone tissue.
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Affiliation(s)
- Romain Vayron
- Laboratoire de Modélisation et de Simulation Multi-Echelle, UMR CNRS 8208, CNRS, Université Paris Est, Créteil 94010, France
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24
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Iijima M, Nakagaki S, Yasuda Y, Handa K, Koike T, Muguruma T, Saito T, Mizoguchi I. Effect of immediate loading on the biomechanical properties of bone surrounding the miniscrew implants. Eur J Orthod 2012; 35:577-82. [PMID: 22952154 DOI: 10.1093/ejo/cjs055] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The aim of this study was to investigate the effect of immediate loading on the biomechanical properties of bone surrounding a miniscrew implant. Forty titanium alloy miniscrew implants were placed on the buccal side of the maxillae and mandibles in four beagle dogs. Twelve pairs of miniscrew implants were immediately loaded with approximately 150 g of continuous force using nickel-titanium coil springs and the remaining 16 implants were left unloaded for 8 weeks. Nanoindentation testing was performed (peak load 10 mN) and the hardness and elastic modulus were calculated. Two series of indentations (in cortical and trabecular bone) for both the compression and tension sides were made. For each site, five indentations were placed approximately 25 μm from the implant-bone interface and 250 μm from the screw thread. The mean hardness and elastic modulus were generally higher in mandibles than maxillae and were higher in cortical bone than in trabecular bone. The trabecular bone near the implant-bone interface on the compression side was significantly harder than that at other locations in trabecular bone. In conclusion, this is the first study that has investigated the biomechanical properties of bone surrounding a miniscrew implant under immediate loading using nanoindentation testing. The mechanical properties of bone surrounding a miniscrew implant may be influenced by immediate loading.
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Affiliation(s)
- Masahiro Iijima
- Division of Orthodontics and Dentofacial Orthopedics, Department of Oral Growth and Development, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu
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25
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Use of micro-CT-based finite element analysis to accurately quantify peri-implant bone strains: a validation in rat tibiae. Biomech Model Mechanobiol 2011; 11:743-50. [DOI: 10.1007/s10237-011-0347-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 08/22/2011] [Indexed: 10/17/2022]
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26
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Mathieu V, Fukui K, Matsukawa M, Kawabe M, Vayron R, Soffer E, Anagnostou F, Haiat G. Micro-Brillouin scattering measurements in mature and newly formed bone tissue surrounding an implant. J Biomech Eng 2011; 133:021006. [PMID: 21280878 DOI: 10.1115/1.4003131] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The evolution of implant stability in bone tissue remains difficult to assess because remodeling phenomena at the bone-implant interface are still poorly understood. The characterization of the biomechanical properties of newly formed bone tissue in the vicinity of implants at the microscopic scale is of importance in order to better understand the osseointegration process. The objective of this study is to investigate the potentiality of micro-Brillouin scattering techniques to differentiate mature and newly formed bone elastic properties following a multimodality approach using histological analysis. Coin-shaped Ti-6Al-4V implants were placed in vivo at a distance of 200 μm from rabbit tibia leveled cortical bone surface, leading to an initially empty cavity of 200 μm×4.4 mm. After 7 weeks of implantation, the bone samples were removed, fixed, dehydrated, embedded in methyl methacrylate, and sliced into 190 μm thick sections. Ultrasonic velocity measurements were performed using a micro-Brillouin scattering device within regions of interest (ROIs) of 10 μm diameter. The ROIs were located in newly formed bone tissue (within the 200 μm gap) and in mature bone tissue (in the cortical layer of the bone sample). The same section was then stained for histological analysis of the mineral content of the bone sample. The mean values of the ultrasonic velocities were equal to 4.97×10(-3) m/s in newly formed bone tissue and 5.31×10(-3) m/s in mature bone. Analysis of variance (p=2.42×10(-4)) tests revealed significant differences between the two groups of measurements. The standard deviation of the velocities was significantly higher in newly formed bone than in mature bone. Histological observations allow to confirm the accurate locations of the velocity measurements and showed a lower degree of mineralization in newly formed bone than in the mature cortical bone. The higher ultrasonic velocity measured in newly formed bone tissue compared with mature bone might be explained by the higher mineral content in mature bone, which was confirmed by histology. The heterogeneity of biomechanical properties of newly formed bone at the micrometer scale may explain the higher standard deviation of velocity measurements in newly formed bone compared with mature bone. The results demonstrate the feasibility of micro-Brillouin scattering technique to investigate the elastic properties of newly formed bone tissue.
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Affiliation(s)
- Vincent Mathieu
- Laboratoire de Biomécanique Biomatériau Ostéo Articulaire, CNRS, Université Paris 7, UMR CNRS 7052, 10 Avenue de Verdun, Paris 75010, France
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Zhao Y, Ovaert TC. Error Estimation of Nanoindentation Mechanical Properties Near a Dissimilar Interface via Finite Element Analysis and Analytical Solution Methods. JOURNAL OF MATERIALS RESEARCH 2010; 25:2308-2316. [PMID: 21528107 PMCID: PMC3082209 DOI: 10.1557/jmr.2010.0295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Nanoindentation methods are well suited for probing the mechanical properties of a heterogeneous surface, since the probe size and contact volumes are small and localized. However, the nanoindentation method may introduce errors in the computed mechanical properties when indenting near the interface between two materials having significantly different mechanical properties. Here we examine the case where a soft material is loaded in close proximity to an interface of higher modulus, such as the case when indenting bone near a metallic implant. Results are derived from both an approximate analytical quarter-space solution and a finite element model, and used to estimate the error in indentation-determined elastic modulus as a function of the distance from the apex of contact to the dissimilar interface, for both Berkovich and spherical indenter geometries. Sample data reveal the potential errors in mechanical property determination that can occur when indenting near an interface having higher stiffness, or when characterizing strongly heterogeneous materials. The results suggest that caution should be used when interpreting results in the near-interfacial region.
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Daegling DJ, Granatosky MC, McGraw WS, Rapoff AJ. Reduced stiffness of alveolar bone in the colobine mandible. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2010; 144:421-31. [DOI: 10.1002/ajpa.21423] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Accepted: 09/14/2010] [Indexed: 11/06/2022]
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Oh WS, Roumanas ED, Beumer J. Mandibular fracture in conjunction with bicortical penetration, using wide-diameter endosseous dental implants. J Prosthodont 2010; 19:625-9. [PMID: 21054640 DOI: 10.1111/j.1532-849x.2010.00646.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Prosthodontic rehabilitation of a patient with an atrophic edentulous mandible presents a significant challenge in restoring esthetics and function. The purpose of this clinical report is to describe fracture of an atrophic edentulous mandible opposing maxillary natural dentition in association with endosseous dental implants. The patient received two wide-diameter implants in the anterior mandible for an implant-assisted mandibular overdenture, in which the implants penetrated the inferior border of the mandible for bicortical stabilization. Three months following implant placement surgery, the patient experienced pain, swelling, and intraoral purulent drainage around the right implant. Panoramic radiograph revealed a fracture of the mandible through the right implant site and signs of infection around the left implant. The implants were removed surgically, and open reduction and fixation of the fracture site were undertaken using a titanium bone fixation plate. This clinical report demonstrates that placement of wide-diameter implants in conjunction with bicortical penetration in a severely atrophic edentulous mandible can risk fracture of the mandible.
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Affiliation(s)
- Won-suk Oh
- Division of Prosthodontics, Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI 48109-1078, USA.
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Natali AN, Carniel EL, Pavan PG. Modelling of mandible bone properties in the numerical analysis of oral implant biomechanics. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2010; 100:158-165. [PMID: 20546967 DOI: 10.1016/j.cmpb.2010.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 02/20/2010] [Accepted: 03/09/2010] [Indexed: 05/29/2023]
Abstract
The biomechanical efficiency of oral implants is deeply influenced by mechanical properties of cortical and trabecular bone in the jaw and, in particular, in the peri-implant region. When the mechanical response of the implant-bone system is analysed by means of numerical models, the effective mechanical properties of bone and the possible change as a function of spatial position must be carefully considered. The procedure presented provides for the attribution of the mechanical properties of bone, considered as anisotropic elastic material, as a function of the spatial position making use of Fourier series and polynomial functions. The procedure is implemented in a general purpose finite element software, adopted to develop biomechanical analyses of prosthetic systems. This procedure allows for an accurate representation of bone tissue properties. Results pertaining to the analysis of commercial oral implants show the potential of the method adopted.
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Affiliation(s)
- Arturo N Natali
- University of Padova, Centre of Mechanics of Biological Materials, Via F. Marzolo 9, I-35131 Padova, Italy.
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Bertassoni LE, Habelitz S, Pugach M, Soares PC, Marshall SJ, Marshall GW. Evaluation of surface structural and mechanical changes following remineralization of dentin. SCANNING 2010; 32:312-319. [PMID: 20853406 PMCID: PMC2981622 DOI: 10.1002/sca.20199] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 08/02/2010] [Indexed: 05/29/2023]
Abstract
This study sought to gain insights into the surface structural and mechanical changes leading to remineralization of dentin. Remineralization was compared between a continuous remineralization approach and a nonbuffered static approach using solutions of the same initial composition. Artificial carious lesions were treated for 5 days and analyzed every 24 h using nanoindentation in water, SEM, and AFM. The continuous approach yielded a recovery of mechanical properties of up to 60% of normal dentin, whereas the static approach led to recovery of only 10%. Image analysis revealed that the static approach yielded the formation of areas suggestive of an apatite precipitate on the surface of the dentin matrix. In contrast, surface precipitate was absent using the continuous approach, suggesting that mineral formed within the lesion and re-associated with the collagenous matrix. This study provided evidence that mechanical recovery of dentin in near physiological conditions is attainable through the continuous delivery of calcium and phosphate ions.
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Affiliation(s)
- Luiz Eduardo Bertassoni
- Division of Biomaterials and Bioengineering, Dept. of Preventive and Restorative Dentistry, University of California, San Francisco
| | - Stefan Habelitz
- Division of Biomaterials and Bioengineering, Dept. of Preventive and Restorative Dentistry, University of California, San Francisco
| | - Megan Pugach
- Division of Biomaterials and Bioengineering, Dept. of Preventive and Restorative Dentistry, University of California, San Francisco
| | - Paulo Cesar Soares
- Department of Mechanical Engineering, Potifícia Universidade Católica do Paraná
| | - Sally Jean Marshall
- Division of Biomaterials and Bioengineering, Dept. of Preventive and Restorative Dentistry, University of California, San Francisco
| | - Grayson William Marshall
- Division of Biomaterials and Bioengineering, Dept. of Preventive and Restorative Dentistry, University of California, San Francisco
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Baker MI, Eberhardt AW, Martin DM, McGwin G, Lemons JE. Bone properties surrounding hydroxyapatite-coated custom osseous integrated dental implants. J Biomed Mater Res B Appl Biomater 2010; 95:218-24. [DOI: 10.1002/jbm.b.31693] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Thurner PJ. Atomic force microscopy and indentation force measurement of bone. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2009; 1:624-49. [DOI: 10.1002/wnan.56] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Alvarez-Arenal A, Lasheras FS, Fernández EM, González I. A jaw model for the study of the mandibular flexure taking into account the anisotropy of the bone. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.mcm.2008.12.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Deformation partitioning provides insight into elastic, plastic, and viscous contributions to bone material behavior. J Mech Behav Biomed Mater 2009; 2:364-74. [DOI: 10.1016/j.jmbbm.2009.01.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 01/16/2009] [Accepted: 01/20/2009] [Indexed: 11/22/2022]
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Clark PA, Clark AM, Rodriguez A, Hussain MA, Mao JJ. Nanoscale characterization of bone–implant interface and biomechanical modulation of bone ingrowth. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2007. [DOI: 10.1016/j.msec.2006.05.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Oyen ML, Ko CC. Examination of local variations in viscous, elastic, and plastic indentation responses in healing bone. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2007; 18:623-8. [PMID: 17546423 DOI: 10.1007/s10856-007-2311-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2005] [Accepted: 01/13/2006] [Indexed: 05/15/2023]
Abstract
A viscous-elastic-plastic indentation model was used to assess the local variability of properties in healing porcine bone. Constant loading- and unloading-rate depth-sensing indentation tests were performed and properties were computed from nonlinear curve-fits of the unloading displacement-time data. Three properties were obtained from the fit: modulus (the coefficient of an elastic reversible process), hardness (the coefficient of a nonreversible, time-independent process) and viscosity (the coefficient of a nonreversible, time-dependent process). The region adjacent to the dental implant interface demonstrated a slightly depressed elastic modulus along with an increase in local time-dependence (smaller viscosity); there was no clear trend in bone hardness with respect to the implant interface. Values of the elastic modulus and calculated contact hardness were comparable to those obtained in studies utilizing traditional elastic-plastic analysis techniques. The current approach to indentation data analysis shows promise for materials with time-dependent indentation responses.
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Affiliation(s)
- Michelle L Oyen
- Department of Biophysical Sciences and Medical Physics and Department of Obstetrics, Gynecology and Women's Health, Minneapolis, USA.
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Natali AN, Gasparetto A, Carniel EL, Pavan PG, Fabbro S. Interaction phenomena between oral implants and bone tissue in single and multiple implant frames under occlusal loads and misfit conditions: A numerical approach. J Biomed Mater Res B Appl Biomater 2007; 83:332-9. [PMID: 17385228 DOI: 10.1002/jbm.b.30800] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
An investigation is carried out on the effects induced in bone tissue surrounding oral implants placed in the premolar region of a mandible by using a numerical approach. In particular, a single implant and a multiple implant frame under loading are considered. The effects of accuracy in the coupling of the connecting bar and implants are evaluated. The mechanical response of the bone-oral implant system, depending on the different mechanical properties assumed for the peri-implant bone tissue during the evolutionary trend of osseointegration, is studied. A further task regard to the comparison of the mechanical state induced in the bone depending on the loading conditions considered. Effects of physiological occlusal loads are compared with ones given by framework defects arising from the specific manufacturing process, such as misfit between the implants and the connecting bar. The investigation offers the basis for an integrated clinical and biomechanical evaluation of the effects induced on peri-implant bone, depending on bone properties, implant system configuration, and the actions induced. Analyses performed show that stress states induced by the investigated type of misfit are comparable to those arising from the application of physiological loading conditions.
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Affiliation(s)
- A N Natali
- Centre of Mechanics of Biological Materials (CMBM), University of Padova, Padova, Italy.
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Kim UK, Chung IK, Lee KH, Swift JQ, Seong WJ, Ko CC. Bone regeneration in mandibular distraction osteogenesis combined with compression stimulation. J Oral Maxillofac Surg 2006; 64:1498-505. [PMID: 16982308 DOI: 10.1016/j.joms.2006.03.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE This study compared modified distraction osteogenesis (DO) protocol with conventional DO protocol on healing bone formation. Computer simulation was performed to understand the mechanical environment of modified DO protocol, which applies compression during the consolidation period. MATERIALS AND METHODS Fifty rats were used in this study. Twenty-five rats in the conventional DO (control) group were sacrificed at postoperative days 11, 21, 28, 35, and 49 after osteotomy. In the modified DO (experimental) group, compression was applied on day 7 after distraction (day 18 postoperatively) for 4 days during the early consolidation period and 25 rats were sacrificed on postoperative day 19, 28, 39, 46, and 53. The histologic and radiographic findings were used to compare the 2 groups. Further, computer simulation was used to predict the mechanical environment of healing bone under conventional and modified DO protocol. RESULTS Radiographic findings showed that the experimental group resulted in denser and wider healing bone. Histologically, the experimental group yielded more mature lamellar bone than the control group. Computer simulation showed that absolute values of tissue strains were nearly double in the control group because of the softer healing tissues. Both the experimental and control groups showed high strains at the ridge crest. Concentrated tensile strain along the distraction direction at the ridge crest might hinder bone formation at the interface, while compressive strain could facilitate the process. CONCLUSION This study proposed a modified DO protocol of adding compression during the early consolidation period of conventional DO protocol. This new technique appears to provide faster and denser bone regeneration.
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Affiliation(s)
- Uk-Kyu Kim
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Pusan National University, Busan, South Korea.
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Natali AN, Pavan PG, Schileo E, Williams KR. A numerical approach to resonance frequency analysis for the investigation of oral implant osseointegration. J Oral Rehabil 2006; 33:674-81. [PMID: 16922741 DOI: 10.1111/j.1365-2842.2006.01610.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Experimental devices based on vibration testing are employed as non-destructive procedures for evaluating implants osseointegration. Their behaviour was evaluated considering the outcome of numerical analysis. The purpose was to use the finite element method for assessing the ability of frequency analysis in detecting the degree of oral implant osseointegration. A three-dimensional model of a mandible was obtained from tomographic survey. A single implant was considered in canine region. Two configurations were analysed, with and without a mass linked to the implant as a cantilever, reproducing experimental devices. Simulation consisted of analysing the response to impulse forces for different osseointegration levels, thus evaluating the biomechanical efficiency of the implant-bone compound. A good correlation between frequency response and osseointegration level was obtained. This was carried out by providing an impulse excitation of the implant that resulted in a vibration pattern. Within the limit of finite element analysis, the outcomes showed that numerical investigation provides understanding the behaviour of testing devices based on frequency measurements, confirming the potential of vibrations technique as non-invasive analysis for osseointegration process.
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Affiliation(s)
- A N Natali
- Centre of Mechanics of Biological Materials, University of Padova, Padova, Italy
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Natali AN, Pavan PG, Ruggero AL. Evaluation of stress induced in peri-implant bone tissue by misfit in multi-implant prosthesis. Dent Mater 2006; 22:388-95. [PMID: 16198407 DOI: 10.1016/j.dental.2005.08.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES The objective of the present work was to use numerical analysis to evaluate the relevance of stress states induced in peri-implant bone tissue by a misfit in a dental fixed prosthesis. Misfits in both mesial-distal and lingual-labial directions were considered to investigate a realistic configuration of the problem. MATERIALS AND METHODS A finite element model of a portion of a mandible with two implants connected by a gold alloy bar was defined on the basis of the morphometric data of a partial edentulous patient. A specific procedure was developed to represent the bar-implant coupling in the case of a misalignment between the implant and central axes of the anchoring site to the bar. Loading conditions related to occlusal forces were also considered. RESULTS The numerical analysis of the implant-bridge misfit showed significant stress effects on the peri-implant bone tissue. For the specific prosthetic configuration considered, the maximum compressive stress was in the range of 40-60 MPa, depending on the misfit considered. The stress level was largely affected by the axial and bending stiffness characteristics of bar-implant compound. SIGNIFICANCE Stress analysis using numerical methods made it possible to estimate stress states with high accuracy in terms of intensity and location. For the case considered, stress induced by misfit was comparable with that related to occlusal forces. Therefore, a possible bar-implant misfit should be carefully considered to ensure the reliability of the prosthetic system.
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Affiliation(s)
- Arturo N Natali
- Centre of Mechanics of Biological Materials, University of Padova, Italy.
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Abstract
A series elastic and plastic deformation model [Sakai, M., 1999. The Meyer hardness: a measure for plasticity? Journal of Materials Research 14(9), 3630-3639] is used to deconvolute the resistance to plastic deformation from the plane strain modulus and contact hardness parameters obtained in a nanoindentation test. Different functional dependencies of contact hardness on the plane strain modulus are examined. Plastic deformation resistance values are computed from the modulus and contact hardness for engineering materials and mineralized tissues. Elastic modulus and plastic deformation resistance parameters are used to calculate elastic and plastic deformation components, and to examine the partitioning of indentation deformation between elastic and plastic. Both the numerical values of plastic deformation resistance and the direct computation of deformation partitioning reveal the intermediate mechanical responses of mineralized composites when compared with homogeneous engineering materials.
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Affiliation(s)
- Michelle L Oyen
- Department of Biophysical Sciences and Medical Physics, University of Minnesota, Minneapolis, MN 55455, USA.
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Natali AN, Pavan PG, Ruggero AL. Analysis of bone-implant interaction phenomena by using a numerical approach. Clin Oral Implants Res 2005; 17:67-74. [PMID: 16441786 DOI: 10.1111/j.1600-0501.2005.01162.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The purpose of the present work is to investigate the interaction phenomena occurring between endosseus dental implants and peri-implant bone tissue. MATERIAL AND METHODS Detailed finite element models are adopted in order to analyze the actual behavior of bone-implant system depending on implant and anatomical site configuration and loading conditions. Different types of titanium dental implants are considered. Implant finite element models are obtained through a reverse engineering procedure and adopting specific software for the reconstruction of geometrical configuration. Anatomical sites are modeled starting from computerized tomography data, according to specific image processing procedures. RESULTS Occlusal static forces are applied to the implants and their effects on the bone-implant interface region are evaluated. The influence of several parameters, such as morphometry of anatomical site or loading condition, on the biomechanical response of bone-implant system is considered. CONCLUSIONS The evaluation of the biomechanical response of implant-bone compound necessarily requires the adoption of accurate numerical models, accounting for the complex geometry of threaded implants, as well as of the anatomy of the patients to be able to provide for reliable results pertaining to stress/strain path on peri-implant bone tissue.
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Affiliation(s)
- Arturo N Natali
- Centre of Mechanics of Biological Materials, University of Padova, Via F. Marzolo 9, I-35131 Padova, Italy.
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Huja SS, Roberts W. Mechanism of osseointegration: characterization of supporting bone with indentation testing and backscattered imaging. Semin Orthod 2004. [DOI: 10.1053/j.sodo.2004.01.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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