Influência de diferentes tipos de conexão implante-pilar nos comportamentos mecânico e biológico de implantes unitários em zona estética de maxila

Abstract

This study aimed to systematically review studies that assessed implant-abutment connection types in order to determine the best performance in terms of esthetic, success and survival for single-tooth implants, regarding the esthetic zone of maxilla. An electronic search was conducted in Medline, Scopus, Embase and the Cochrane Library databases to identify clinical studies on single-tooth implants with external hexagon (EH), internal hexagon (IH) and/or morse taper (MT) connections. These studies also needed to describe at least one of the following outcomes: esthetics, survival rate, success rate or marginal bone loss (MBL). Tables were generated to summarize the included studies and reports were assessed for bias using the Cochrane risk of bias tool. Of the 875 articles identified in the initial search, 25 were selected for the final review. As result, it was found that the most common technical complications were abutment screw loosening and crown-cement loosening, and the most common biological complications were dehiscences and recessions . Dehiscences, crown-cement loosening and ceramic fracture were the most frequent complications for EH, IH and MT, respectively. Esthetic was favorable for all connections, but IH performed better in anterior maxilla, despite the better results for marginal bone loss, success and survival of MT. The annual failure rate (AFR) was 0.90 for anterior maxilla in general and 0.19, 0.31 and 2.19 for MT, EH and IH, respectively. This review suggests that MT has the best performance in terms of survival, marginal bone loss and success rate, while IH showed better results for aesthetic parameters. Despite that, IH appears to have the best results in esthetic evaluations, even though all connections presented satisfactory values. However, more controlled studies are needed to draw stronger evidence, since the generated in this study was considered very low .