A Comparative Evaluation of Crestal Bone Levels in Mandibular Implant-Retained Overdentures using Delayed and Immediate Loading Protocols: An in vivo Study

Aim: The purpose of the study was to evaluate the changes in peri-implant bone quality, crestal bone level and the implant stability (periotest) for mandibular implant retained overdentures with ball attachments using delayed and immediate loading protocols. Materials and methods: Two Alpha-Bio dental implants were placed in the anterior part of the mandible in ten completely edentulous patients. Five patients were loaded under immediate loading protocols and other five following delayed. Crestal bone loss and bone quality were assessed around each implant. Periotest values were recorded for each implant at 3, 6 and 12 months after loading. Results: Two implants were lost and were excluded from the study, however mean crestal bone loss around implants was 0.81 mm from the time of prosthetic loading to 12 months after prosthetic loading was seen and no significant result was found between the two groups for the crestal bone loss and the periotest values. Though the periotest value decreased (indicates increased stability) over the time period. The bone density changes were significant for both the groups at coronal level at all time intervals but at middle level significant only after 12 months of prosthetic loading, although individual variation was high. Conclusion: This study concluded that the changes in crestal bone level and periotest values were insignificant for the two groups. But, the implant stability increased over the time and the crestal bone loss was evident with decreased rate over the period of time. There was wide individual variation for the bone density changes but overall increase in the density was seen.