Abstract:

Objective To study the stress distribution under dynamic loading in the presence or absence of an abutment buffer layer by using three-dimensional finite element analysis. Methods A three-dimensional solid geometric model of an implant in a human mandible was established on the basis of CT scan data. A buffer-free abutment prosthesis and a buffer-abutment abutment prosthesis were installed above the implant. The buffer layer was made of high-density polyethylene. A vertical load of 200 N and a horizontal load of 100 N (45°) were concentrated on the centers of the implant restorations of the two groups. Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface were compared via three-dimensional finite element analysis. Results Stresses on the implant neck and body, abutment neck and body, central bolt neck and body, and bone interface on the abutment with a buffer layer were significantly lower than those on the abutment without a buffer layer. Conclusion The increase in the buffer layer of the abutment neck significantly reduced stress on the implant neck, abutment, central bolt neck, and bone interface.

Key words: implant, abutment, buffer layer, stress, finite element analysis