Clinical outcomes following surgical treatment of peri-implantitis at grafted and non-grafted implant sites: a retrospective analysis

Background: This retrospective analysis aimed at comparing the clinical outcomes following combined surgical therapy of peri-implantitis at initially grafted and non-grafted (i.e., pristine) implant sites. Methods: A total of 39 patients exhibiting 57 implants diagnosed with peri-implantitis (i.e., 16 implants at grafted and 41 implants at non-grafted sites) were included. Each subject had received a combined (i.e., implantoplasty and augmentative therapy) surgical treatment procedures at respective implants (grafted sites: 10 patients, 16 implants, non-grafted sites: 29 patients, 41 implants). A chi-squared test (chi(2)) was used to assess whether the initial grafting procedure did affect the treatment outcomes (i.e., disease resolution, bleeding on probing (BOP), probing pocket depths (PD)). The mean follow-up period was 41.9 +/- 34.75 months. Results: At the patient level, disease resolution (i.e., absence of BOP and PD >= 6 mm) was obtained in 4/10 (40%) at grafted and in 7/27 (24.1%) at non-grafted implant sites (p = 0.579). BOP reductions was found to be 60.64 +/- 40.81% at non-grafted and 77.45 +/- 30.92% at grafted sites (p = 0.778). PD reductions amounted to 2.20 +/- 2.22 mm at nongrafted and 1.57 +/- 1.54 mm at grafted sites (p = 0.969). Conclusions: The initial bone-grafting procedures at the implant sites did not influence the effectiveness of combined surgical therapy of peri-implantitis.