Background Adjunctive antimicrobials may improve the outcome of subgingival instrumentation, but due to the lack of evidence no antimicrobial agent is recommended for subgingival re-instrumentation (SRI). The aim of this study was to clinically, immunologically and microbiologically evaluate the potential additional effects of amino-acid sodium hypochlorite (AA-NaOCl) and cross-linked hyaluronic acid (xHA) to SRI at 3 and 6 months.Methods At the time point of reevaluation during systematic periodontal therapy, eligible patients were allocated to either control group receiving SRI of residual pockets, or test group with the adjunctive AA-NaOCl and xHA. Per patient 2 study sites were selected and clinical periodontal parameters (PD, CAL, BOP, and pocket closure), immunological biomarkers and 8 major periopathobionts were analyzed at baseline, after 3 and 6 months. Detection of IL-1β and MMP-8 was carried out using ELISA, the abundance of the periopathobionts by qPCR.Results Improvements in the clinical parameters were demonstrated in all 42 included patients. In the test group an additional PD reduction by 0.50 mm (1.38, 95% CI range: 1.11-1.65 vs. 0.88, 95% CI range: 0.62-1.14; p = 0.008) and CAL gain by 0.57 mm (1.07, 95% CI range: 0.70-1.44 vs. 0.50, 95% CI range: 0.24-0.76; p = 0.017) was found compared to the control group. The percentage of residual pockets decreased by 88.1% (n = 37) in the test, and 38.1% (n = 16) in the control group. There was no significant change in the immunological parameters. The abundance of 5 periopathobionts significantly decreased in the test group.Conclusions The adjunctive application of AA-NaOCl and xHA significantly improved the clinical and microbiological outcome 3 and 6 months after SRI.Trial Registration This trial was registered in the German Clinical Trials Register (ID: DRKS00017415 at 03/06/2019).
Jungbauer et al. (Sat,) studied this question.