Biomechanical analysis of implant-supported prostheses in a severely resorbed mandible using 3-dimensional finite element method

Implant supported fixed prosthesis;Biomechanical behavior;Bone resorption;Cantilever;Maximum von Mises stress;Finite element method.;617.6

Ghaith Alom치과보철학전공 ;

University:서울대학교 대학원

关键词: Implant supported fixed prosthesis;    Biomechanical behavior;    Bone resorption;    Cantilever;    Maximum von Mises stress;    Finite element method.;    617.6;   

Others  :  http://s-space.snu.ac.kr/bitstream/10371/161683/1/000000157938.pdf

美国|英语

来源: Seoul National University Open Repository

【 摘 要 】

1. Purpose The purpose of this study was to evaluate the biomechanical behavior of a buccal cantilever and to compare it with other prosthetic designs to determine the best design in terms of stress distribution within the bone of a buccally resorbed partially edentulous mandible.2. Material and methodsBased on patient computed tomography (CT) scan data, three finite element models were created. Each model composed of the severely resorbed mandible, the first premolar, the second molar and the implants that replaced the second premolar and the first molar. The first model had two implants placed based on bone quantity creating a buccal cantilever (CP2). The second model had two prosthetic-driven implants (BP2). The third model had three prosthetic-driven implants (BP3). In all models preload of 466.4 N on the abutment screw was applied. A load simulating chewing cycle was applied at seventy-five degrees to the occlusal surfaces of the prostheses. The maximum load magnitude was 262 N. The maximum von Mises stresses were demonstrated and compared in cortical and cancellous bone as well as the implant components.3. ResultsThe results showed that the cantilever model exhibited better stress distribution compared to the other models. The overall maximum von Mises stress in each model was concentrated on the premolar abutment for CP2 (1036 MPa), on the molar screw for BP2 (982 MPa) and on the premolar abutment for BP3 (922 MPa). In the cortical bone, the maximum von Mises stress was around the neck of the implants with values as follows: 293 MPa in CP2, 348 MPa in BP2 and 791 MPa in BP3. For the cancellous bone von Mises stress was concentrated at the apex of the premolar implants for BP2 and BP3. For CP2 the maximum von Mises stress was around the implant neck. The recorded values were 26 MPa in CP2, 348 MPa in BP2 and 791 MPa in BP3. Von Mises stress peaks in the implants components did not exhibit significant difference.4. ConclusionConsidering the severely resorbed partially edentulous posterior mandible, placing implants based on the available bone quantity is more desirable than prosthetic-driven implant placement in terms of biomechanical behavior. The cantilever model created the highest maximum von Mises stress among the three models with regard to the prosthesis. However, when considering the bone, the cantilever model recorded the lowest maximum von Mises stress.