Peri-implant inflammation and marginal bone level changes around dental implants in relation to proximity with and bone level of adjacent teeth.

OBJECTIVES: This retrospective study assessed radiographic bone changes and prevalence of inflammation around teeth and neighbouring implants supporting a single-unit fixed dental prosthesis (FDP), in relation to implant- positioning and characteristics.

MATERIAL AND METHODS: Patients with an implant-supported FDP in function for at least 1 year were recruited. The radiographic horizontal and vertical position of the implants were identified. Probing depth (PD), bleeding on probing (BOP) and radiographic bone level around implants and adjacent teeth at the time of placement, prosthesis delivery, and the most recent review were assessed.

RESULTS: 98 patients with 195 implants were evaluated for a mean of 37.8 months. Survival rate was 99.6% and success ranged from 31.3% to 91.3% when different success criteria were utilized. Significantly greater interproximal bone loss around teeth and higher prevalence of interproximal peri-implant inflammation occurred when the horizontal distance of BL implants was <1 mm, but not with TL implants. There was no significant impact of the corono-apical positioning of the implants on marginal bone loss.

CONCLUSION: Proximity of implants to adjacent teeth of <1 mm leads to increased prevalence of inflammation and interproximal bone resorption at the teeth adjacent to bone level implants.