The impact of conical design of dental implant and osteotomy shape on the insertion process and primary stability.

Abstract

This study investigated the impact of dental implant shape (conical vs. cylindrical) and pilot-hole geometry (conical vs. cylindrical) on primary stability. Finite element analysis was employed to simulate the insertion process and push-in test. Three implantation scenarios were examined: a cylindrical implant in a cylindrical pilot-hole (cy-cy model), a conical implant in a cylindrical pilot-hole (co-cy model), and a conical implant in a conical pilot-hole (co-co model). These configurations were evaluated based on the maximum insertion torque, insertion energy, stiffness, and holding power of the implant-bone construct. Given peri-implant damage during the insertion process and push-in test, elastic-plastic-damage properties were used to model bone material behavior. Results showed that despite lower implant-bone engagement in the co-cy scenario, its maximum insertion torque was 81 % higher than the cy-cy model. However, the stiffness and the holding power were 31 % and 44 % lower, respectively. Additionally, the co-co scenario demonstrated a significant increase in maximum insertion torque compared to other models while maintaining stiffness and holding power comparable to the cy-cy configuration, making it the most favorable model. This study also highlighted the importance of insertion energy as a potential indicator of implant-bone construct engagement, suggesting its consideration alongside other traditional stability factors. Further research, including in-vitro experiments, is necessary to refine pilot-hole geometry based on implant body design, ultimately enhancing primary stability and improving clinical outcomes in dental implantation.