Evaluation of Platform Switched Laser-Lok implant on the stress distribution of crestal boneby Finite Element Analysis

This research analyzes the effect of platform switching design of Laser-Lok implants on the stress distribution in crestal bone of the Laser-Lok implant collar and its surrounding bone interface through Finite Element Analysis (FEA). The results are compared with control implant to show the effect of Laser-Lok implants platform switching design on the stress distribution in crestal bone. Three-dimensional modeles of the Laser-Lok implant with platform switching, the control implant (a Laser-Lok implant with same size abutment), and the mandible bone is generated for the FEA. Each implant is assembled on the mandible bone in pre-molar considering the proper boundary condition. It should be mentioned that the control implant is similar in all features to the independent implant (LL) except from the size of abutment. After meshing and considering the proper elements regarding the mastication forces and normal condition, a 100N of axial and oblique loading with angles of 15 and 45 angle is applied to the centre of the abutments of both Independent Laser-Lok implant and control implant on same condition. Under different loading conditions the independent implant has shown better results and lower stress distribution on surrounding crestal bone, comparing with control implant. Results demonstrate that the platform switching design will not only ignore the Laser-Lok fixture advantage of reducing the shear forces and bone loss but also will reduce stress concentration on the critical points of upper parts of the crestal bone. Hence transferring the stress distribution to the lower parts of the crestal bone-collar interface. It should be considered that only reducing the shear forces is not enough to decrease crestal bone loss. In this regard, excluding the biological factors should also be considered. Therefore, the platform switching design is proposed as a way to inhibit the interstitial fluid flow to surrounding tissues by creating a platform on the abutment-fixture interface and it is a biological advantages. Total results indicate that Laser-Lok implant with platform switching has not only all the advantages of control implant in reducing the shear forces on crestal bone-collar interface but also has its own advantage of reducing the crestal bone loss by eliminating the biological factor.