LAUSR

AIM To evaluate the potential adjunctive effect of a resorbable collagen membrane covering a xenogeneic bone replacement graft in the reconstructive surgical therapy of peri-implantitis. MATERIALS AND METHODS Forty-three patients (43 implants) diagnosed with peri-implantitis associated with intra-bony defects were treated with a surgical reconstructive approach that included a xenogeneic bone substitute material. Additionally, resorbable collagen membranes were placed over the grafting material at sites randomly allocated to the test group; conversely, no membranes were placed in the control group. Clinical outcomes, including probing pocket depth (PPD), bleeding and suppuration on probing (BoP & SoP), marginal mucosal level (REC) and keratinized mucosa width (KMW), were recorded at baseline and 6 and 12 months after surgery. Radiographic marginal bone levels (MBL) and patient-reported outcomes (PROs) were assessed at baseline and 12 months. A composite outcome (success) was evaluated at 12 months, which included absence of BoP/SoP, PPD ≤5 mm and reduction of buccal marginal mucosal level (buccal REC) of ≤1 mm. RESULTS At 12 months, no implants were lost and treatment success was observed at 36.8% and 45.0% of implants in the test and control groups, respectively (p=0.61). Similarly, there were no significant differences between groups in terms of changes of PPD, BoP/SoP, KMW, MBL or buccal REC. Post-surgical complications were observed in the test group only (e.g. soft tissue dehiscence, exposure of particulate bone graft and/or resorbable membrane). Longer surgical times (~10 minutes; p<0.05) and higher levels of self-reported pain at 2 weeks (p<0.01) were observed in the test group. CONCLUSIONS This study failed to demonstrate the presence of added clinical or radiographic benefits of the use of a resorbable membrane to cover a bone substitute material within the reconstructive surgical therapy of peri-implantitis associated with intra-bony defects.