Evidence-Based Criteria for an Ideal Abutment Implant Connection-A Narrative Review

Long-term success with a dental implant restoration relies on a stable connection between the abutment and the implant. The purpose of this article is to review current knowledge of the abutment interface, identify problems that develop due to wear and mismatch of parts, and use a problem list to propose a solution. The objective was to provide a concise overview that clinicians can then use to choose a system that addresses the problems of the abutment implant interface.

Manufacturing methods will result in surface variations across the surface of the abutment and implant. Microgaps change in dimension upon function due to wear. Bacterial leakage can lead secondary to functional wear, and the microgap will get larger. The increase in the microgap with function has been clinically verified. Micromotion will result in larger areas of surface gap in both flat and conical connections, with gaps larger than the size of bacteria.

For an ideal abutment, an implant system must have high tolerances for manufacturing with minimal gap formation along the abutment to implant surface; a connection that is resistant to micromotion; screws that have minimal deformation during loading; and a microgap less than 1 micron which is maintained during implant function.