Maxillary Four Implant-retained Overdentures via Locator® Attachment: Intermediate-term Results from a Retrospective Study

Abstract

Background: Maxillary overdentures have been utilized to restore oral function in scenarios where limited bone structure represents a drawback for financial issues and for cases where oral hygiene is uncertain. Purpose: The aim of this study was to evaluate the intermediate-term clinical outcome of four locator attachment retaining maxillary overdentures and to test their reliability. Materials and Methods: A retrospective study was conducted from January 2007 to October 2013. After the placement of four maxillary dental implants and a healing period of approximately 3 months, all the implants were restored with locator-retained overdentures with partial palatal coverage. Subjects and implant characteristics, implant position (anterior vs posterior maxilla), bone quality, and opposing dentition were recorded. Peri-implant clinical parameters and marginal bone loss (MBL) were evaluated after delivery of the final prosthesis and annually thereafter. The performance of locator components and the prosthetic restoration were also recorded at follow-up. Results: A total of 104 implants were placed in 26 subjects (11 women, 15 men; mean age, 64 years; age range, 55-76 years). One implant failed before loading. One subject dropped out of the study during a mean follow-up period of 46 months (range: 7-73 months), achieving an overall survival rate of 95.2%. Clinical parameters revealed healthy tissues around most of the implants, with low scores of plaque and bleeding indices. At the last follow-up evaluation, the mean MBL was 1.7±1.1mm (0.4-2.6mm). Regression model analysis indicated that MBL for implants in the posterior maxilla was significantly higher than that for implants in the anterior maxilla (p=.0487). Overall, 26 technical and prosthetic complications were reported. Conclusion: Within the limitations of this study, maxillary four implant-retained overdentures via Locator attachment seem to be a predictable alternative for oral rehabilitation.