Supragingival Microbiota Alterations in Individuals With Sleep Bruxism: A Pilot Study.

BACKGROUND

Sleep bruxism (SB) is an oral behaviour associated to jaw clenching or grinding of the teeth. Its aetiology is most likely multifactorial; however, recent studies suggested that SB is associated with activation of the sympathetic nervous system. Dysbiosis of the oral microbiota is linked to oral and systemic diseases. The relationship between supragingival microbiota and SB remains unexplored.

OBJECTIVE

This study aimed to investigate the association between SB and the composition of the supragingival microbiota.

METHODS

Nineteen metabolically and orally healthy subjects were recruited. After SB diagnosis, supragingival microbiota samples were collected. Microbial DNA was extracted and subjected to 16S rRNA gene sequencing. Amplicon sequence variant (ASV) analysis method was used to correlate the composition of supragingival microbiota with SB.

RESULTS

Bacterial diversity decreased in the SB group. ASV_200 (Actinomyces) and ASV_94 (Morococcus) were enriched in the SB individuals, whereas ASV_405 (Morococcus) was enriched in the controls. The role of the decreased bacterial diversity as well as the enrichment of specific ASV in the mechanism explaining the genesis of SB remain to be determined.

CONCLUSION

The differences in the composition of the supragingival microbiota may lead to the assessment of important questions in the fields of oral microbiota composition and sleep medicine.