Evaluation of stress distribution by different abutment and crown materials on implant components and peripheral bone: A three dimensional finite element analysis

Aim: The aim of this study is to evaluate and compare the stress distributions of hybrid abutment and crown materials produced with different materials by using finite element stress analysis method in order to assist the clinician in deciding on the restorative material to be used in implant-supported prostheses in the maxillary anterior region. Material and Method: In our study, on 1 bone level implant with a diameter of 4 mm and a length of 11 mm in the right maxillary number (11 tooth region); 15 groups 3D analysis were created which hybrid abutment produced using with Poliviniliden Florür (PVDF), BioHPP® (Biocompatible High Performance Polymer), lithium disilicate, monolithic zirconia, hybrid ceramic and crown restorations which produced using monolithic zirconia, lithium disilicate and hybrid ceramic materials. After the Poisson ratios and elastic modulus values of the materials and bone used in the study were loaded into the program, analyzes were made by applying an inclined force of 178 N and 45º from the palatal surface 2 mm below the cutting edge. As a result of the analysis, von Mises, the highest compressive and highest tensile stress values and their distribution formed in the implant components and cortical and cancellous bone, were evaluated by comparing them with each other. Results: It was observed that the stress values occurring in the cortical and cancellous bone were similar between the groups, the von Mises stress values in the implants were concentrated in the implant-abutment connection and the neck region of the implant, the highest values occured in the group where the BioHPP® abutment was used with the hybrid ceramic crown, and the lowest stress value occurred in the group where the zirconia abutment was used together with the hybrid ceramic crown. It has been observed that the stress on the abutments is mostly concentrated in the step regions of the abutments and the hybrid abutment model made of monolithic zirconia accumulates more stress in its structure compared to the other abutment models. Among crown materials, hybrid ceramic crown material showed lower von Mises and minimum principal stress values compared to monolithic zirconia and lithium disilicate crowns. There was no biomechanical difference between the groups for the stress values in the screw and the highest stress values in the whole system occurred in the ti base abutments. Conclusion: Within the limitations of this study, besides the similarity of the stress values in the implants and bone between the groups; more stress accumulation was observed in abutment materials with high elastic modulus than in abutment materials with low elastic modulus. The stress values in the abutment groups were more affected by the abutment material change than the crown material change. Key Words: Finite Element Stress Analysis, Ti Base, Different Abutment Materials, PVDF, BioHPP®.