Preliminary Study to Evaluate Marginal Bone Loss in Cases of 2- and 3-Implant-Supported Fixed Partial Prostheses of the Posterior Mandible.

PURPOSE

The purpose of this study was to evaluate, by radiographic examinations, the marginal bone resorption around implants in cases of 2 and 3 implant-supported fixed partial prostheses (FPPs) at the posterior mandible.

METHODS

A retrospective study of 41 patients (23 males, 18 females) of an average age of 67 years (range, 53-85), with 2 and 3 implants-supported FPPs in the posterior mandible that were treated during 2006 to 2015. The mean follow-up time was 6.32 years (range, 2-10). Twenty-four patients had FPPs on 2 implants (a total of 48 implants). Seventeen patients had FPPs on 3 implants (a total of 51 implants). Clinical and radiographic follow-up examinations were performed. All radiographs were analyzed for changes in marginal bone height surrounding the implants.

RESULTS

The mean marginal bone loss around the most mesial implant was slightly higher in the 2-implant group (0.833 mm) compared with the 3-implant group (0.431 mm). The correlation between the mean marginal bone loss around the most mesial implant and the number of implants was of borderline value (P = 0.055).

CONCLUSIONS

Considering the limitations of this preliminary study, the authors found that the mesial implant in the 2-implant group is more susceptible to marginal bone loss.