Effectiveness of modified and control protocols for the surgical therapy of combined peri-implantitis-related defects. A retrospective analysis

Abstract

Objectives: To compare the clinical effectiveness of control and two modified protocols for surgical therapy of combined peri-implantitis-related defects. Materials and Methods: A total of n = 36 patients (n = 40 implants) diagnosed with combined supra- and intrabony defects were identified for this retrospective analysis. All protocols considered access flap surgery, granulation tissue removal and implant surface decontamination using a titanium brush. The control combined protocol included implantoplasty at supracrestal/ buccal- and reconstructive therapy at intrabony components using a particulate natural bone mineral + a native collagen membrane (CM) (n = 11 patients, n = 11 implants, CP). The modified protocols included the augmentation at both supra- and intrabony defect components using either a collagen-stabilized natural bone mineral (BOC) (n = 15 patients, n = 15 implants, MP1), or BOC mixed with autogenous bone chips + CM (n = 10 patients, n = 14 implants, MP2). Linear mixed effects analyses were used to assess the changes in clinical parameters (i.e., bleeding on probing – BOP, probing pocket depth – PD, and mucosal recession – MR) over time (i.e., 6 and 12 months) and the impact of the treatment groups (CP, MP1, MP2). Results: At 12 months, median BOP and PD reductions amounted to −58.33% and − 1.16 mm in the MP1, to −62.50% and −1.95 mm in the MP2, and to −66.67% and −0.83 mm in the CP groups, respectively. The associated MR changes ranged between 0.00 and 0.08 mm. The survival rates were 100% in all groups. Conclusions: All treatment protocols were associated with short-term improvements in the clinical parameters investigated.