Adjunctive Xylitol Therapy Drives Targeted Oral Microbiome Modulation Without Disrupting Community Structure in Stunted Children: A 16S rRNA Sequencing Study

Background: Stunting is associated with impaired immune function and increased susceptibility to oral dysbiosis; however, microbiome-targeted interventions in this population remain underexplored. This study aimed to evaluate the effect of adjunctive xylitol therapy following scaling and root planing (SRP) on clinical parameters and salivary microbiota in children with stunted growth. Methods: Eighteen participants were allocated into two groups: SRP alone (n = 9) and SRP with xylitol gum (n = 9). Gingival Index (GI) and Oral Hygiene Index-Simplified (OHI-S) were assessed at baseline and 14 days post-intervention. The salivary microbiota was analyzed using 16S rRNA sequencing, encompassing taxonomic composition, alpha and beta diversity, and correlation network analysis. Results: Both groups showed significant reductions in GI, while OHI-S improved significantly only in the SRP + xylitol group. Microbiota analysis demonstrated an increase in Firmicutes and Proteobacteria and a decrease in Bacteroidota, particularly in the xylitol group. At the genus level, Lautropia increased, whereas periodontopathogenic species, including Prevotella intermedia, Tannerella forsythia, and Treponema denticola, decreased. Alpha diversity (Shannon and Simpson indices) and beta diversity (UniFrac and PCA) showed no significant changes, indicating preservation of overall microbial structure. Correlation analysis revealed synergistic interactions among commensal taxa and antagonistic relationships with pathogenic groups. Conclusions: Adjunctive xylitol therapy improves clinical outcomes and induces targeted microbiome modulation without disrupting overall diversity, supporting ecological rebalancing as a potential mechanism for microbiome-based interventions in stunted children.