Investigation of the stress created by 30 degree sloped implant design specially developed for all on four technique on the implant and the surrounding tissue using three dimensional finite element stress analysis method

Aim: In this study, it is aimed to examine the effectiveness of the 30° sloped implant design specially developed for the All-on-Four technique in reducing the stress on the implant and the surrounding bone tissue by using the finite element stress analysis (FESA) method and to evaluate the effect on the long-term success of the implants. Material and Method: According to the All-on-Four technique, traditional design (Quattrocone, Medentica) implants of 4.3x11mm were placed in the anterior region in a vertical position, while conventional design (Quattrocone, Medentika) and special design (Quattrocone30, Medentika) implants of 3.8x13mm and 4.3x13mm were placed in the posterior region in a 30° angled position. A total of four implant groups, a titanium based acrylic hybrid prosthesis and edentulous mandible models were experimentally prepared in the computer environment. The implants were placed in the mandible model according to the All-on-Four technique, and the model was completed with a titanium based acrylic hybrid prosthesis. The stress values on the implants and the surrounding bone were examined by FESA method by applying a total of 300N force, 100N from each point obliquely, to the buccal tubercle crests of the first premolar, second premolar and first molar teeth. Results It was observed that Von Mises stress values on implants with neck structure and a 30° angle specially developed for the All-on-Four technique were higher in both 3.8mm and 4.3mm diameters, whereas fewer compression forces were generated in the surrounding cortical and cancellous bone. Conclusion: According to this study, it was observed that the implant design with the neck structure and 30° angle, specially developed for the All-on-Four technique, creates less stress on the surrounding bone tissue compared to the traditional implant design. Keywords: Dental implant, All-on-Four, sloped implant, finite element analysis, Ekrem CANBULAT, Expertise Thesis Ondokuz Mayis University-Samsun, October-2022