Efficacy of reconstructive surgical therapy at peri-implantitis-related bone defects. A systematic review and meta-analysis

Objectives The present systematic review aimed at evaluating the efficacy of reconstructive surgical therapy at peri-implantitis-related bone defects. Methods Studies reporting on outcomes of reconstructive surgery at peri-implantitis-related bone defects at 12 months were identified through an electronic search. Following data extraction, two different sets of meta-analyses were performed. Primarily, controlled studies were used to evaluate the potential benefit of reconstructive surgical therapy over controls. Secondly, overall outcome of reconstructive surgical therapy was assessed by comparing baseline values with outcomes at 12 months. Results were expressed as weighted mean differences (WMD) or risk ratios (RR). Heterogeneity was described by I-2 and prediction intervals. Results The potential benefit of reconstructive techniques over control procedures was evaluated in three studies, representing a total of 116 implants. Altogether, 16 studies reported on the outcome of reconstructive measures at 12 months after surgery. The meta-analyses identified a larger improvement in marginal bone levels (MBL, WMD = 1.7 mm) and in defect fill (WMD = 57%) for test procedures, but found no differences for clinical measures (reduction of probing depth (PD) and bleeding on probing (BOP). Changes of clinical attachment and soft tissue levels were not considered. In terms of overall outcome, therapy resulted in improved MBL (WMD = 2.0 mm) and CAL (WMD = 1.8 mm), in recession (WMD = 0.7 mm), in reduced PD (WMD = 2.8 mm) and in reduced BOP (Implants: RR = 0.4/Sites: RR = 0.2). None of the included studies addressed patient-reported outcome measures. Conclusions The available evidence on reconstructive therapy at peri-implantitis-related defects is limited by (a) the low number of controlled studies, (b) the lack of controlled studies for commonly used procedures, (c) the heterogeneity between studies and (d) the choice of outcome measures. A high variability for predicted outcomes at 12 months was noted. The interpretation of the demonstrated larger MBL gain for test procedures is difficult as graft material may not be distinguishable from newly formed bone. Potential aesthetic and patient-reported advantages remain to be demonstrated.