Reconstructive surgical therapy of peri-implantitis: 3-year results of a randomized clinical trial

17L5C ORAL COMMUNICATION CLINICAL RESEARCH – PERI-IMPLANT BIOLOGY

Background: Various treatment protocols of peri-implantitis involving surgical therapies with open flap debridement procedures, resective or reconstructive modalities have been documented to achieve variable success. Surgical NO-reconstructive approaches have been suggested to have limited effectiveness in terms of the resolution of inflammation in the long term. Therefore, much more interest has been intensified regarding the efficacy of biomaterials used in reconstructive approaches.

Aim/Hypothesis: The aim of this study was to investigate the 3-year clinical/radiographic outcomes of reconstructive surgical therapy of peri-implantitis using a bone substitute combined with two different bioresorbable barrier membranes, either collagen membrane (CM) or concentrated growth factor (CGF).

Materials and Methods: A total of 72 patients who had at least one implant diagnosed with peri-implantitis and needed to be scheduled for reconstructive therapy of a peri-implant intrabony defect were included. Peri-implantitis case was defined as increased probing depth (PD) compared to previous examinations with bleeding on probing (BOP) and/or suppuration and radiographic evidence of peri-implant bone loss beyond crestal bone level changes resulting from initial bone remodeling. The patients were randomly assigned to receive a bone substitute filling in combination with either CM or CGF. Intrabony components were filled with a bone substitute (BioOss spongiosa granules; Geistlich, Wolhusen, Switzerland) and covered with a CM (Bio-Guide, Geistlich Biomaterials) or CGF membrane. The plaque INDIAx (PI), gingival INDIAx (GI), BOP, PD, clinical attachment level (CAL), mucosal recession (MR) and radiographic vertical defect depth (VDD) values were evaluated at 1 and 3 years postoperatively.

Results: One patient from the CM group and two patients from CGF group were discontinued from the study due to severe pus formation during the study time periods. At 1 year, the mean PD, CAL and vertical defect depth (VDD) values were statistically significant in favor of the CM group. However, at the 3-year follow-up, both CM and CGF groups revealed comparable mean VDD values. Moreover, the mean values of defect fill (DF) at both 1 year and 3 years follow-up in the CM group were not statistically significantly different from that observed in the CCF group.

Conclusions and Clinical Implications: Both reconstructive surgical treatment modalities yielded improved clinical and radiographic outcomes at both 1 year and 3 years postoperatively compared to baseline conditions. Despite the fact that the clinical significance may be considered as weak, the procedure using a collagen membrane in combination with a bone substitute seems to have favorable clinical outcomes compared to the CGF membranes combined with bone substitute filling.

Keywords: peri-implantitis, surgical treatment, barrier membranes, collagen, concentrated growth factor.