Biomechanical response of implant systems placed in the maxillary posterior region under various conditions of angulation, bone density, and loading.
OBJECTIVE
The aim of this study was to determine the relative contribution of changes in implant system, position, bone type, and loading condition on the biomechanical response of a single-unit implant-supported restoration using nonlinear 3-dimensional finite element analysis (3D FEA).


METHODS
FEA models of a single-unit (crown) restoration supported by the Frialit-2 implant and MH-6 abutment or the Straumann standard implant with the Straumann solid abutment were used. Each system was analyzed by FEA with both straight and 20-degree angled abutments. Simulated implant placement was performed in the maxillary premolar area with 3 variations in implant orientation relative to the residual ridge. Analysis of each orientation was conducted for each of 4 bone quality types described by Lekholm and Zarb, with lateral and axial loading conditions imposed. The effect of each variable was expressed as a percentage of the total sum of squares as computed using analysis of variance.


RESULTS
Larger strain values were noted in cortical bone with lateral force and the Frialit-2 system. Bone strain increased with decreasing bone density and was affected primarily by bone quality. Implant stress was influenced mainly by implant position.


CONCLUSIONS
Better stress/strain distribution is possible when implants are placed along the axis of loading with multiple areas of cortical contact. The Straumann solid abutment performed better as a force-transmission mechanism.
Lin
Chun-Li
CL
Department of Mechanical Engineering, Chang Gung University, Tao-yuan, Taiwan.
Wang
Jen-Chyan
JC
Ramp
Lance C
LC
Liu
Perng-Ru
PR
D000539:Alveolar Process / Q000601:surgery; D001641:Bicuspid; D001696:Biomechanical Phenomena; D015519:Bone Density; D003198:Computer Simulation; D003442:Crowns; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D019250:Dental Implants, Single-Tooth; D017267:Dental Prosthesis Design; D003799:Dental Stress Analysis / Q000379:methods*; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008437:Maxilla; D017711:Nonlinear Dynamics; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing