Clinical applications of angled abutments ── a literature review

Dental implants have been proven to be an effective way of restoring the masticatory ability to completely or partially edentulous patients. But when clinicians deal with undesirable implant orientation caused by poor bone conditions, an angled abutment is often the treatment of choice for prosthodontic restorations. A search of articles related to the success rate, stress analysis, and bone response to loading of angled abutments was performed in order to understand the rationale for their current clinical applications. Evidence shows that the clinical performance of angled abutments is comparable to that of straight abutments with respect to both soft-tissue responses and general survival rates. However, in vitro studies of stress/strain analyses of angled abutments can only agree that stress/strain levels increase as abutment angulation increases. Three analytical techniques including the photo elastic technique, strain gauge analysis, and finite element analysis have been applied for analyzing angled abutments. Further comparative studies are required using these three techniques because some quantitative aspects are still inconclusive such as how much stress is introduced upon a certain degree of abutment angulation. (Chin Dent J, 24(1):15-20, 2005)