Clinical Status and Salivary aMMP-8 Evaluation of 0.12% Chlorhexidine Versus MicroRepair® ABX Mouthwash in the Non-Surgical Management of Plaque-Induced Gingivitis: A Randomized Controlled Trial

Objectives: To compare the adjunctive efficacy of a MicroRepair® mouthwash containing an antibacterial complex (ABX), composed of cetylpyridinium chloride, magnolol, and honokiol, with 0.12% chlorhexidine (CHX) in the management of generalized plaque-induced gingivitis, assessing clinical periodontal parameters, salivary activated matrix metalloproteinase-8 (aMMP-8) levels, and patient-reported outcomes over 6 months. Methods: A randomized, controlled, parallel-group clinical trial included 40 systemically healthy adults with generalized gingivitis and was reported in accordance with CONSORT 2025 guidelines. Following professional oral hygiene according to the Guided Biofilm Therapy (GBT) protocol, participants were randomly allocated to ABX or 0.12% CHX, used twice daily for 14 days. Clinical parameters, including Full-Mouth Bleeding Score (FMBS, primary outcome), Full-Mouth Plaque Score (FMPS), Probing Pocket Depth (PPD), Clinical Attachment Level (CAL), Gingival Recession (REC), and Modified Lobene Stain Index (MLSI), were recorded at baseline, 2 weeks, 1, 3, and 6 months. Salivary aMMP-8 levels were assessed at baseline and 2 weeks. Heavy smokers were excluded, and smoking status was evaluated as a potential covariate. Non-parametric tests were applied (p < 0.05). Results: Both groups showed significant reductions in FMBS and FMPS over time (p < 0.05), with no intergroup differences for the primary outcome at any follow-up at the patient level. Patient-level analyses did not reveal consistent differences across secondary parameters. At the tooth level, lower FMPS values were observed in the trial group at 2 weeks and 1 month (p < 0.05), with earlier PPD reduction. CAL, and REC remained stable. Salivary aMMP-8 levels decreased significantly in both groups without intergroup differences. Patient-reported outcomes were comparable. Smoking status was balanced between groups and was not significantly associated with treatment allocation or the main clinical outcomes. Conclusions: No significant differences were observed between ABX and CHX for the main clinical and molecular outcomes, supporting its potential use as an adjunct in gingivitis management.