The Effect of Locator Attachment and Ball-O-Ring Attachment on Bone Height Change in Implant Retained Overdenture

Abstract

Objectives. This study was conducted to evaluate and compare the effect of locator attachment and Ball-O-ring attachment on the peri-implant crestal bone level changes in edentulous patients rehabilitated with implant retained lower over denture. Methods. Twenty edentulous patients (male) were participating in this study, they were rehabilitated by mucosa supported maxillary complete denture and implant retained mandibular over denture by two implants installed in the canine region, patients were divided into two equal groups according to the type of attachment used, the locator attachment was used for group I and Ball-O-ring attachment was used for group II. Peri-implant crestal bone level changes were assessed using intra-oral radiographs taken with the standardized long cone paralleling technique using custom made acrylic template and the Rinn-xcp system. Periapical radiographs were taken every six months to complete a period of 18 months follow up period. The marginal bone loss at different intervals was obtained by calculating the difference in bone height at that interval from the base line measurement and statistically analyzed (t-test P < 0.05). Results. The result of this study showed that the time has significant effect on the mean values of the peri-implant bone height on both groups. Moreover, group I had significantly less bone resorption from insertion to twelve months in compare to group II. Conclusion. The insignificant difference observed between comparing the peri-implant bone loss between the two groups indicates that the two treatment modalities are effective for the rehabilitation of lower denture. Locator attachments have the ability to control the amount bone loss. It could be advantageous in cases where the retention of implants retained overdentures is compromised.