Immediate Microbiological Efficacy of Electrolytic Cleaning Compared to Chlorhexidine in Peri-Implantitis: A Randomized Pilot Study

Background: Implant-surface decontamination is required before reconstructive treatment of peri-implantitis, but no protocol has demonstrated consistent clinical superiority. Objective: To compare the immediate reduction in recoverable bacterial target DNA after electrolytic cleaning and 0.2% chlorhexidine (CHX). Materials and Methods: Forty nonsmoking patients with peri-implantitis (one implant per patient) were randomized to GalvoSurge (n = 20) or CHX (n = 20). Microbiological samples were collected from the exposed implant surface before and immediately after the assigned decontamination protocol and standardized terminal sterile-saline irrigation. Five periodontal pathogens were assessed using semiquantitative DNA-based real-time PCR (qPCR). Laboratory categories were converted to an exploratory summed ordinal score (range 0–15). A post hoc cumulative logit model compared post-treatment scores between groups while adjusting for the pretreatment score. Results: Pretreatment scores were higher in the GalvoSurge group (median 4.5, IQR 3.0–6.0) than in the CHX group (median 3.0, IQR 2.75–4.0; p = 0.043). After baseline adjustment, GalvoSurge was associated with lower post-treatment scores (adjusted common odds ratio for a higher score, 0.047; 95% profile-likelihood CI, 0.009–0.202; p < 0.001). Unadjusted analyses also favored GalvoSurge for absolute reduction (median 4.0 vs. 1.0), relative reduction (83.3% vs. 26.7%), and post-treatment score (median 1.0 vs. 2.0; all p < 0.001). Complete target non-detection occurred in 7/20 (35.0%) and 2/20 (10.0%) patients, respectively (Fisher’s exact p = 0.127). Conclusions: In this exploratory randomized pilot sample, GalvoSurge was associated with a greater immediate reduction in recoverable bacterial target DNA than CHX after adjustment for pretreatment score. DNA-based qPCR does not distinguish viable from non-viable bacteria; therefore, the findings do not establish bacterial killing, sterility, or long-term clinical superiority.