Repeated delivery of chlorhexidine chips for the treatment of periimplantitis: A multicenter, randomized, comparative clinical trial.

"This is the peer reviewed version of the following article:Machtei, EE, Romanos, G, Kang, P, et al. Repeated delivery of chlorhexidine chips for the treatment of periimplantitis: A multicenter, randomized, comparative clinical trial. J Periodontol. 2020; 1– 10. https://doi.org/10.1002/JPER.20-0353 which has been published in final form at doi: https://doi.org/10.1002/JPER.20-0353 . This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."BACKGROUND: Periimplantitis is a challenging condition to manage and is frequently treated using non-surgical debridement. The local delivery of antimicrobial agents has demonstrated benefit in mild to moderate cases of periimplantitis. This study compared the safety and efficacy of Chlorhexidine gluconate 2.5 mg chip (CHX chips) as an adjunctive treatment to sub-gingival debridement in patients afflicted with periimplantitis. METHODS: A multi-center, randomized, single-blind, two-arm, parallel Phase-3 study was conducted. Periimplantitis patients with implant pocket depths (IPD) of 5-8 mm underwent sub-gingival implant surface debridement followed by repeated bi-weekly supra-gingival plaque removal and Chlorhexidine chips application (ChxC group) for 12 weeks, or similar therapy but without application of ChxC (control group). All patients were followed for 24 weeks. Plaque and gingival indices were measured at every visit while IPD, recession and bleeding on probing were assessed at 8,12,16,24 week. RESULTS: 290 patients were included: 146 in the ChxC group and 144 in the control. At 24 weeks, a significant reduction in IPD (p = 0.01) was measured in the ChxC group (1.76 ± 1.13 mm) compared to the control group (1.54 ± 1.13 mm). IPD reduction of ≥2 mm was found in 59% and 47.2% of the implants in the ChxC and control groups, respectively (p = 0.03). Changes in gingival recession (0.29 ± 0.68 mm vs. 0.15 ± 0.55 mm, p = 0.015) and relative attachment gain (1.47 ± 1.32 mm and 1.39 ± 1.27 mm, p = 0.0017) were significantly larger in the ChxC group. Patients in the ChxC group that were <65 years exhibited significantly better responses (p<0.02); likewise, non-smokers had similarly better response (p <0.02). Both protocols were well tolerated, and no severe treatment-related adverse events were recorded throughout the study. CONCLUSIONS: Patients with periimplantitis that were treated with an intensive treatment protocol of bi-weekly supra-gingival plaque removal and local application of Chlorhexidine chips had greater mean IPD reduction and greater percentile of sites with IPD reduction of ≥2 mm. as compared to bi-weekly supra-gingival plaque removal. (Clinicaltrials.gov NCT02080403). This article is protected by copyright. All rights reserved