WEN-WEI CHANG2026-10-162026-10-162024-12-01Pure ID: 15050196Pure UUID: 9ef09a46-ca9f-4bc0-8e95-26f408efea7f10.1186/s12903-024-04251-4https://www.scopus.com/pages/publications/85190808904https://scholars.csmu.edu.tw/handle/123456789/30364Background: This study examines the oral health benefits of heat-killed Lacticaseibacillus paracasei GMNL-143, particularly its potential in oral microbiota alterations and gingivitis improvement. Methods: We assessed GMNL-143’s in vitro interactions with oral pathogens and its ability to prevent pathogen adherence to gingival cells. A randomized, double-blind, crossover clinical trial was performed on gingivitis patients using GMNL-143 toothpaste or placebo for four weeks, followed by a crossover after a washout. Results: GMNL-143 showed coaggregation with oral pathogens in vitro, linked to its surface layer protein. In patients, GMNL-143 toothpaste lowered the gingival index and reduced Streptococcus mutans in crevicular fluid. A positive relationship was found between Aggregatibacter actinomycetemcomitans and gingival index changes, and a negative one between Campylobacter and gingival index changes in plaque. Conclusion: GMNL-143 toothpaste may shift oral bacterial composition towards a healthier state, suggesting its potential in managing mild to moderate gingivitis. Trial registration: ID NCT04190485 (https://clinicaltrials.gov/); 09/12/2019, retrospective registration.enjournal article