Abstract
<title>Abstract</title> <p>Background To assess the feasibility of comparing clinical outcomes, treatment efficiency, and subgingival bacterial community changes associated with subgingival air polishing using erythritol powder versus scaling and root planing (SRP) in supportive periodontal therapy. Methods In this pilot randomized clinical trial, 20 patients diagnosed with periodontitis (Stage II–III, Grade B–C) in supportive periodontal therapy were allocated (1:1) to subgingival air polishing with erythritol powder or SRP. Probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were assessed at baseline and 6 months. Subgingival plaque samples were analyzed using 16S rRNA gene sequencing at the bacterial family level to describe changes in relative abundance of selected taxa. Patient-reported discomfort (VAS) and treatment duration were recorded at baseline. Given the pilot nature of this study and the small sample size, all microbiological findings should be considered exploratory and hypothesis-generating only. Results Both interventions produced significant improvements in clinical parameters over 6 months, with no statistically significant differences between groups. Subgingival air polishing with erythritol was associated with significantly shorter treatment time and a non-significant trend toward lower patient-reported discomfort. Exploratory family-level 16S rRNA analysis revealed descriptive differences in the relative abundance of bacterial families between groups following treatment; however, these findings should be interpreted with caution given the small sample size, the compositional nature of the data, and the limited taxonomic resolution of family-level analysis. Conclusions In this pilot trial, subgingival air polishing with erythritol powder demonstrated clinical outcomes comparable to SRP while offering potential advantages in treatment efficiency. Exploratory microbiological data suggest descriptive differences in bacterial family-level abundance patterns between groups, warranting confirmation in larger, adequately powered studies with higher taxonomic resolution. Trial registration: ClinicalTrials.gov, NCT07344805, registered on November 19, 2025. Retrospectively registered.</p>