Abstract
AIM: The objective of this systematic review and meta-analysis was to evaluate the influence of non-surgical periodontal therapy (NSPT) on subgingival microbiota in systemically healthy patients with periodontitis. METHODS: A systematic literature search was conducted in Medline, Embase, LILACS, and the Cochrane Library, supplemented by a manual search for studies investigating the effect of NSPT on subgingival microbiota in systemically healthy patients. RESULTS: In this review, 115 studies were included, of which 41 used checkerboard DNA-DNA hybridisation technology, 30 real-time quantitative PCR, 36 bacterial culture, and 8 16S ribosomal ribonucleic acid (rRNA) gene sequencing technology. Meta-analyses showed a significant decrease in mean counts of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Treponema denticola (T. denticola), Porphyromonas gingivalis (P. gingivalis), Tannerella forsythia (T. forsythia), Eubacterium nodatum (E. nodatum), Prevotella intermedia (P. intermedia), and Campylobacter rectus (C. rectus) after NSPT. Supportive periodontal care provided a further decrease in mean counts of P. gingivalis and T. denticola at 6 months after NSPT. Qualitative analysis of 16S rRNA gene sequencing studies indicated significant effects of NSPT on the relative abundance of selected disease-and health-associated species and genera, whereas findings on changes in alpha and beta diversity in the subgingival microbiome were heterogeneous. CONCLUSION: This systematic review showed that NSPT leads to significant reduction of mean abundance of disease-associated microbial species. However, 16S rRNA gene sequencing studies reported heterogeneous findings, which may be associated with methodological aspects. To deepen the understanding of the effect of NSPT on subgingival microbiota, further studies, powered for microbiome changes and with clustered analysis of site-specific samples, are needed.