Effect of bollard coping and locator attachment on implant stability and patient satisfaction in single implant assisted mandibular overdenture (in-vivo study)

Abstract

Objective This study was performed to evaluate the effect of bollard coping and locator attachment on immediately loaded single implant retained complete mandibular overdenture. Patients and methods Twenty completely edentulous patients were selected from the Outpatient Clinic, Prosthodontics Department, Faculty of Dental Medicine, Al Azhar University. For each patient complete maxillary and mandibular conventional complete denture were constructed. The patients were divided into two equal groups: group I: patients were treated by single implant assisted mandibular overdenture retained with a new design (bollard coping); group II: patients were treated by single implant assisted mandibular overdenture retained with locator attachment. The bollard coping retention was achieved by engagement of the undercut in the bollard coping to the chemical-curing silicone soft liner in the denture. The locator attachment retention was achieved by the mechanical interlock between the attachment and the metal housing in the denture. The stability of implants was measured by using the Osstell implant stability quotient (ISQ) system and patient satisfaction was evaluated by using a questionnaire. Measurements were taken at baseline, 3, 6, and 12 months after implant insertion. Independent t-test was used for comparison between groups while the comparison of within each group by time was done by one-way analysis of variance followed by post-hoc Tukey test. Results Patient satisfaction and ISQ values results showed higher values in group I than group 2 without any statistically significant difference. ISQ values in both groups over time showed a statistically significant difference between the baseline and 6 and 12 months, between 3 and 12 months, and between 6 and 12 months values. There were statistically nonsignificant difference resulted from the comparison of 3 and 6 months values. Conclusion There was an increase in the ISQ, and retention values for both groups during the follow-up period, but the difference was statistically insignificant between the two groups.