Background: To investigate the middle-term effect on bone remodeling of different timings for different implant placement (immediate versus delayed). Methods: Patients with an anterior maxillary failing tooth were treated by single-crown supported by dental implant. Subjects were retrospectively analyzed for 3 years and assigned to one of two predictor groups: nine immediate versus 10 delayed implant placement (1-2 months after tooth extraction). The crestal bone loss around dental implants was measured with the cone beam computerized tomography by fusing pre-operative and post-operative data. Results: The percentage of volume loss registered at 1-year follow-up (%ΔV) was of 7.5% for the immediate group, which was significantly lower (p-values ≤ 0.0002) than the loss of 24.2% for the delayed group. At 3 years, there was a significant difference (p-values = 0.0291) between the two groups, respectively, with a volume loss of 14.6% and 27.1%. When different times were compared, the percentage of the volume loss for the immediate group was different (p-value = 0.0366) between the first and third year (7.5% and 14.6%, respectively). For the delayed group, no significant difference was registered between the 1- and 3-year follow-up. Conclusions: The bone loss around dental implant-supported single-crown with different timing of insertion appeared higher for the delayed group than the immediate group.
Keywords: cone beam computerized tomography imaging; delayed loading; immediate placement.