Surgical treatment of peri-implantitis: Prognostic indicators of short-term results

To evaluate the clinical and radiographic short-term (6 months) effect of surgical treatment of peri-implantitis, and to identify prognostic indicators affecting the outcome using a multilevel statistical model.

A total of 143 implants (45 patients) with a diagnosis of progressive peri-implantitis (progressive bone loss (PBL) ≥2.0 mm and bleeding on probing (BoP)/suppuration) received surgical treatment. Clinical and radiographic parameters were assessed 6 months postoperatively. Potential prognostic indicators on subject, implant and site level prior to surgery were analysed to evaluate the effect on individual and composite outcomes using multilevel logistic regression analysis.

At the 6-month evaluation, none of the implants demonstrated PBL and 14% of the implants were registered with the absence of bleeding and no pocket probing depth ≥6 mm. Multilevel regression analysis identified, among others, suppuration, pocket probing depth >8 mm, bone loss >7 mm and the presence of plaque as criteria associated with the outcome.

Resective peri-implantitis surgery seemed to reduce the amount of peri-implant inflammation. However, most of the sites continued to have BoP/suppuration. Thus, long-term maintenance and evaluation is warranted. The effect of treatment was reduced by some prognostic indicators such as the presence of suppuration prior to interception and peri-implant bone loss exceeding 7 mm.