Effect of the attachment system on the biomechanical and clinical performance of overdentures: A systematic review.

Abstract

STATEMENT OF PROBLEM\nOverdentures can improve the quality of life of elderly patients compared with conventional complete dentures. Different attachment systems can be used to retain these prostheses, but which system results in better function, mechanical performance, and patient comfort is unclear.\n\n\nPURPOSE\nThe purpose of this systematic review was to evaluate randomized clinical trials to compare overdentures supported by either bar and clip or ball and O-ring attachments for retention, masticatory efficiency, bone loss, and patient satisfaction.\n\n\nMATERIAL AND METHODS\nA literature search was conducted in the PubMed and Web of Science databases. From 163 studies, 16 randomized clinical trials were included in this systematic review based on the inclusion and exclusion criteria. The risk of bias was evaluated according to the RevMan software Risk of Bias Table\xa0(RoB Table), and only the studies with a low or intermediate risk of bias were included in the review.\n\n\nRESULTS\nFrom the limited number of studies, the attachment type did not affect the masticatory quality of the patients, bone loss marginal to the implants, or the degree of patient satisfaction. However, overdentures with the bar and clip attachment tended to have higher initial retention than the ball and O-ring system.\n\n\nCONCLUSIONS\nBoth the bar and clip and ball and O-ring attachment systems presented similar\xa0clinical performance regarding mechanical and functional properties and patient satisfaction.