Investigation of implant, abutment, screw and bonestress distribution by using finite element method inimplant retained fixed bridge prosthesis prepared withdifferent superstructure materials.

Aim: Aim of this study is to evaluate the stresses of the implant and implant surrounding tissues by using different superstructure materials by using the finite element method. Material and methods: In our study, titanium implants with a diameter of 3.3 mm and 4.8 mm were placed in the 2nd premolar and 2nd molar region of manadibula, respectively. Bone modeling was performed in order to analyse stress distribution by finite element method. 4 different 3-member bridge prostheses were designed by using porcelain fused metal, monolithic zirconia, porcelain fused zirconia and PEEK substructures on the titanium abutments. Analyzes were performed by vertical and oblique forces applied to the occlusal surface. Results: Oblique forces were found more destructive than vertical forces in all study grups. Stresses depending on the effect of the forces in the bone were affected by compression forces in 4 groups. Stresses in implant, abutment and screw were found around neck area. Stresses in crown were found around connector and margin areas. Conclusion: It is concluded that the stresses that occur as a result of the applied forces occur at least in zirconia generally. Key Words: PEEK, monolithic zirconia, zirconia ,finite element analysis, dental implant