Salivary microbiome responses to chlorhexidine and Coriandrum sativum essential oil mouthwashes in patients with periodontitis in a randomized 2-week clinical trial

To compare the short-term salivary microbiome effects of a Coriandrum sativum essential oil (CSEO) mouthwash, chlorhexidine (CHX) as a benchmark comparator, and water in patients with periodontitis.

In this randomized three-arm trial, participants with periodontitis rinsed twice daily for 14 days with water, CSEO, or 0.12% CHX. Preclinical anti-Porphyromonas gingivalis and fibroblast cytotoxicity assays informed CSEO concentration selection. Shotgun metagenomic sequencing was performed on 54 saliva libraries, two per participant, from 27 participants sampled at baseline and week 2 (H2O n = 9, CSEO n = 8, CHX n = 10). Alpha diversity, within-subject Bray-Curtis change, and differential abundance were analysed longitudinally.