THE EFFECT OF IMPLANT DIAMETER ON STRESS, STRAIN, AND SAFETY FACTOR IN SCREWS AND ABUTMENTS BASED ON FEA

Abstract

The loss of anterior teeth has a significant impact on masticatory function and facial aesthetics, making dental implants a widely used rehabilitative solution. The success of implants is greatly influenced by geometric design, particularly the diameter of the fixture, which plays a role in distributing load. This study aims to analyze the influence of variations in implant diameter on stress distribution, strain, and safety factor in the screw and abutment areas using a three-dimensional Finite Element Analysis (FEA) approach. Three implant models with fixture diameters of 3.75 mm, 4.00 mm, and 5.00 mm were simulated using a vertical physiological load of 130.5 ± 73.6 N, assuming Ti-6Al-4V material and orthotropic properties of the mandibular bone. The results showed that Model 2 (4.00 mm diameter) had the most balanced stress distribution and the highest safety factor value at the abutment (12.251), while Model 3 exhibited the lowest stress and strain at the screw. Model 1 had the lowest biomechanical performance with the highest stress and strain and the lowest abutment safety factor (10.611). It can be concluded that variations in fixture diameter significantly affect the mechanical performance of the implant system, and a diameter of 4.00 mm is recommended as the most optimal design to support long-term strength and stability.