Stress Distribution Analysis in Bone Adjacent to Implant in Various Abutment-Implant Connection Designs Using Finite Element Analysis.

Natural teeth have a periodontal ligament with viscoelastic properties, while implants are connected to the bone with a strong connection and osseointegration; therefore, the stress on the adjacent bone of the implant and its prosthetic components is more than that of natural teeth. This study examines the connection (Morse different tapers) to find the most suitable length and Morse angle of the taper and the angle of applying the force on the tooth to create the least stress using finite element analysis. Geometrical and 3D models of the mandible bone, implant, and its prosthetic components were made using engineering software and sizes of the DIO implant manufacturer. In this modeling, 4 types of connections with different lengths and tipping angles were designed, and then a constant force of 200 N was applied to them. Stress distribution was investigated in this experiment in 12 different conditions: 2 Morse taper lengths (1.3 mm and 2.6 mm), 2 Morse taper angles (11° and 16°), and 3 force application angles (0°, 30°, and 45°). By increasing the length of the Morse taper from 1.3 mm to 2.6 mm, the amount of stress in the bone adjacent to the implant and its prosthetic components is reduced. By increasing the tipping angle of the Morse taper from 11° to 16°, the amount of stress in the bone adjacent to the implant, the fixture, and the abutment decreases. Furthermore, by increasing the tipping angle of the morse from 11° to 16° the amount of stress in the implant screw increases. Increasing the angle of the force applied to the implant increases the amount of stress in the bone adjacent to the implant and its prosthetic components. The best Morse taper connection to create the least stress on the bone surrounding the implant and its prosthetic components is a long taper Morse with a length of 2.6 mm and a greater tipping angle (16°), This stress is less at the vertical force application angle.