Supragingival dental biofilm profile and biofilm control during orthodontic treatment with fixed orthodontic appliance: A randomized controlled trial

Objective: The effectiveness of supragingival dental biofilm control during orthodontic treatment and changes in the bacterial profile were analyzed. Design: Sixty-four participants aged 12 - 22 years (57% female) were included in the study. Participants underwent orthodontic treatment with fixed appliances and were randomly assigned to one of the three groups, which during a period of one month: (I) used chlorhexidine digluconate (CHX), (II) used high concentration of fluoride (F) gel and (III) performed standard oral hygiene. The plaque and gingivitis index, pH of biofilm and white spot lesions (WSL) were assessed. Changes of the bacteria in the biofilm were analyzed by the quantitative polymerase chain reaction Results: Increase in the plaque index, pH of biofilm, and WSL was observed during orthodontic treatment with standard oral hygiene. Large interindividual variability was present, and the effects of one -month use of fluorides and CHX on clinical parameters were not significant. Despite standard hygiene the abundance of studied biofilm bacteria increased - the most Streptoccocus mutans (14.2x) and S. salivarius (3.3x), moderate Veillonella parvula (3x) and the least S. sobrinus (2.3x) and Agregatibacter actinomycetemcomitans (1.9x). The use of CHX reduced S. sobrinus (2.2x) and A. actinomycetemcomitans (1.9x). Fluoride use reduced A. actinomycetemcomitans (1.3x) and S. sobrinus (1.2x). Fluorides better controlled S. mutans than CHX. Conclusion: Bacterial biomass in supragingival biofilm increased during treatment with metal orthodontic appliances, with greater increase in cariogenic bacteria than periopathogens. Fluoride controlled S. mutans , while CHX S. sobrinus and A. actinomycetemcomitans .