Effects of Non-Surgical Periodontal Therapy on Dental Plaque Microbiome.
Level 4 - case-series / case-control
Prospective single-arm before-and-after study without a separate control group
PubMed 42589241 · doi:10.3390/ijms27156584
What was done
Whole-metagenome shotgun sequencing was performed on dental plaque samples collected from 39 patients with Stage II or III generalized periodontitis before and 3 to 4 months after scaling and root planing (SRP; 78 total samples). The authors evaluated clinical periodontal indices (probing depth, clinical attachment level, bleeding on probing, and plaque index) alongside microbial taxonomic composition and predicted functional potential using the Carbohydrate-Active Enzymes (CAZy) database.
What was found
Periodontal therapy led to significant reductions in probing depth, clinical attachment level, bleeding on probing, and plaque index (exact numerical values not reported in the abstract). Sequencing identified 3.18 million non-redundant genes and 12,353 microbial species, showing increased gene and species richness and overall community restructuring post-treatment. Established and candidate pathogens, including Porphyromonas gingivalis, Escherichia coli, and Burkholderia multivorans, decreased significantly. Tannerella forsythia showed a marked reduction that did not remain statistically significant after false discovery rate correction. Health-associated early colonizers, including multiple Actinomyces species and Streptococcus cristatus, increased. CAZy annotation revealed significant post-treatment differences in carbohydrate-active enzymes, particularly glycosyltransferases.
Why it matters
This study provides whole-metagenome shotgun resolution showing that mechanical non-surgical periodontal therapy not only reduces classic periodontopathogens but also increases microbial richness and alters predicted carbohydrate-active enzymatic pathways.
Limits
The study was small (n = 39) and lacked a healthy or untreated control group, preventing comparison against natural temporal microbiome variation. Follow-up was limited to 3–4 months post-treatment. Functional capabilities were computationally predicted from metagenomic data rather than directly measured via metatranscriptomics or metabolomics, and specific quantitative values and effect sizes were omitted from the abstract.
Cited by
- contradicts Research shows that immediately following a deep dental cleaning, oral pathogen levels in the mouth increase.