Comparative Biofilm Profiling of Healthy and Cavitated Root Surfaces Across Age Groups Using 16S rRNA Sequencing

This preliminary clinical study investigated the microbial composition of dental biofilms on healthy root surfaces and cavitated root caries lesions in two age cohorts: adults under 65 years and those aged 65 and older. The goal was to assess how aging and caries status influence root surface biofilm diversity and structure. For that, forty adults (23 women, 17 men) were enrolled. Biofilm samples were collected directly from clinically healthy and cavitated root surfaces. Microbial profiling was performed using 16S rRNA gene sequencing to evaluate diversity metrics and community composition. The results show that cavitated root surfaces harbored significantly higher microbial diversity compared to healthy root surfaces, as indicated by the Shannon diversity index. In contrast, healthy surfaces exhibited lower diversity and greater species dominance, confirmed by Simpson’s index. Age-related differences in biofilm composition were also evident, with older adults showing distinct microbial communities compared to younger participants. In conclusion, both age and cavitation presence significantly influence biofilm composition on root surfaces. These differences in microbial diversity and dominance may inform future clinical strategies for managing root caries, particularly in older adults. Further research is needed to assess the implications of these microbial patterns on treatment outcomes.