Effect of different implant–abutment connections on the supporting structures of implant retained overdenture

Abstract

This study was carried out to compare the amount of marginal bone loss around two different implant abutment connections, implant abutment cone and tri-lobe connections in mandibular implant supported overdenture. Fourteen male patients were selected according to the inclusion criteria; conventional complete dentures were constructed and delivered to the patients, implant surgeries were performed after full history taking, intra oral examination and pre-operative CBCT, all the patients enrolled in this study had the two implant abutment connection types, the implants with cone connection were inserted in patients' right side while implants with tri-lobe connection were inserted in left side both into canine region at crestal bone level. Fixtures were left submerged to osseointegrate for 3 months. After 3 months the submerged fixtures were uncovered and the ball abutments were screwed. The lower dentures were modified to direct pick-up the attachments turned into implant supported over dentures. The amount of marginal bone loss was evaluated at the time of functional prosthetic loading, 6 months and 12 months later using CBCT. Data were collected, checked, revised, tabulated and statistically analyzed. The amount of marginal bone loss around the two implant abutment connections that were compared throughout the whole study period showed that the average marginal bone loss around tri-lobe implant abutment connections was statistically significant higher than marginal bone loss around the cone connection after 12 months of functional prosthetic loading.