Influence of anisotropy on peri-implant stress and strain in complete mandible model from CT

This paper reveals the influence of elastic anisotropy for the peri-implant stress and strain in personalized mandible. First, from CT data, the individual geometry of the complete range of mandible was well reproduced, also the separation between cortical and cancellous bone. Then, by an ad hoc automatic mesh generator integrated with anisotropic material assignment function, high quality anisotropic finite element model of the complete mandible was created, with two standard threaded implants embedded in posterior zone. The values of principal stress and strain in surrounding bone were evaluated under buccolingual oblique loading, and compared to that of the same FE model with equivalent isotropic material. Results of the analyses demonstrated that the percentage increase of stress and strain in anisotropic case reached up to 70%. It is concluded that anisotropy has significant effects on peri-implant stress and strain and careful consideration should be given to its use in biomechanical FE studies.

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