Longitudinal Microbiome Changes in Supragingival Biofilm Transcriptomes Induced by Orthodontics.

Area of Science:

• Oral microbiome research
• Microbial transcriptomics
• Longitudinal cohort studies

Background:

• Oral diseases are linked to dysbiosis in the supragingival microbiome.
• Most current associations are from cross-sectional studies, limiting understanding of temporal changes.
• Orthodontic treatment offers a unique prospective model to study these changes.

Purpose of the Study:

• To prospectively examine longitudinal changes in the supragingival microbiome's composition and function during orthodontic treatment.
• To correlate microbial shifts with clinical measures of oral health.
• To identify specific microbial taxa associated with treatment-induced oral health changes.

Main Methods:

• Longitudinal cohort study of 24 adolescent orthodontic patients.
• Saliva and plaque samples collected pre-bonding and at 1, 6, and 12 weeks post-bonding.
• RNA sequencing of plaque and saliva for microbiome analysis; clinical indices (BOP, GI, PD, PI) recorded.

Main Results:

• Clinical oral health measures (GI, PI, PD) significantly worsened post-bonding.
• Health-associated species (e.g., Streptococcus sanguinis) decreased in relative abundance.
• Disease-associated taxa (e.g., Selenomonas sputigena, Leptotrichia wadei) increased; specific salivary taxa predicted future bleeding on probing.

Conclusions:

• Fixed orthodontic treatment induces significant longitudinal shifts in the supragingival microbiome.
• These shifts are characterized by an increase in pathogenic bacteria and a decrease in beneficial species.
• Findings provide insights into microbial dysbiosis during treatment and identify potential targets for future interventions.