Design of a custom angled abutment for dental implants using computer-aided design and nonlinear finite element analysis.

Computer-aided design/computer-aided manufacturing (CAD/CAM) custom abutments have been attracting more and more attention due to their advantages of accuracy fit and esthetic emergence profile. However, the CAD key technology for custom abutments has been seldom studied as well as their biomechanical behavior. This paper explored a novel method to design a CAD/CAM custom angled abutment, evaluated the biomechanical performance of the whole system and compared the difference between the custom and the conventional abutment through 3D nonlinear finite element analysis (FEA). Firstly, the digital data of the dental casts at the healing abutment level was acquired by optical scanner. Thus the position of the healing abutment and the implant can be determined by CAD technology. The custom angled abutment was then designed according to the need of restoration and esthetics with CAD software. The described system can eliminate wax and cast, create an esthetic anatomical emergence profile and provide a satisfactory angle correction. Simulation results indicate that there was no distinct difference in the stress distribution and magnitude of implant-bone interface and screw using the custom or the conventional angled abutment.