Biomechanical Assessment of Multiple Internal Implant–Abutment Connection Designs Using Finite Element Analysis

Different implant–abutment connection designs can affect the bending and torsion resistance of the implant system. This chapter aims to study the mechanical behavior differences under various internal implant–abutment connection modes. Four experimental groups were built based on four internal platform connection types: hexagon connection (HC), octagonal connection (OC), torx connection (TC) and tri-channel connection (TCC). A bone level implant (Φ4.3×10 mm), straight abutment (Φ5.0 mm), and identical screw were used in the finite element models. The 200 N oblique load was applied to zirconia crown cemented over the abutment to perform static compressive simulation. Moreover, a torsional moment of 60 N.cm was applied to the outer surface of the abutment for torsion simulation. The equivalent stress and abutment angular rotation of each group were calculated and compared. The results displayed that the maximum peak stress values of both implants and abutments were found in the TCC group. The greatest rotational freedom of abutments was also observed in the TCC group. Among all connections, the TCC group exhibits the most severe stress concentration and the largest rotational freedom. Compared to other groups, the HC group demonstrates better performance in terms of resistance to bending and rotation.