Bar versus Locator attachments for maxillary implant overdentures opposed by implant supported mandibular overdentures. Clinical and radiographic evaluation

Abstract

Purpose: The aim of this short-term clinical trial was to evaluate clinical and radiographic outcomes of Bar and Locator attachments used to retain maxillary implant overdentures opposed by implant supported mandibular overdentures. Material and methods: Ten patients wearing conventional maxillary denture and implant supported mandibular overdentures received 4 implants in the maxillary arch using 2 stage surgical approach. Six months later maxillary overdentures were connected to the implants with locator (group 1) or bar (group 2) attachments. Plaque index, bleeding index, probing depth, implant stability, and marginal bone loss (using Cone beam computerized tomography) were evaluated at time of overdenture delivery, 6 months and 12 months later. Results: Plaque and gingival indices increased significantly with time in bar group only. Bar overdentures recorded significant higher plaque and gingival scores than locator overdentures. No significant difference in pocket depth and implant stability was noted between time intervals or groups. Total marginal bone loss for locator group was significantly higher than bar group after 6 and 12 months. For both groups, marginal bone loss around canine implants was significantly higher than bone loss around premolar implantsConclusion: Within the limits of this study, it could be concluded that both locator and bar retained maxillary overdentures are successful treatment options for patients complaining from instability of maxillary dentures opposed by implant retained mandibular denture. However, locator attachments are advantageous in terms of peri-implant soft tissue health and bar attachments are advantageous regarding peri-implant alveolar bone preservation.