The effect of nHAP dentifrice on bacteria in the plaque biofilm model.

The purpose of the study is to evaluate the antimicrobial efficacy of toothpaste containing Nano-hydroxyapatite (nHAp) against oral bacteria within an in vitro plaque biofilm model. A plaque biofilm model was constructed by culturing a dual-species biofilm composed of Porphyromonas gingivalis and Streptococcus mutans on human enamel-dentin discs coated with saliva. The biofilm was exposed to toothpaste solution twice a day, and the culture medium was replaced. The pH of the culture medium was measured to evaluate the acidogenicity of the biofilm. After 96 hours, the biofilm was collected for bacterial counting, and the biofilm was evaluated by scanning electron microscopy and confocal laser scanning microscopy. nHAP toothpaste exhibited the smallest decrease in pH. Bacterial counting, scanning electron microscopy, and confocal laser scanning microscopy all showed that the nHAP group owned the best antibacterial effects. The toothpaste containing nHAP effectively inhibits bacterial growth within an in vitro dental plaque biofilm model, indicating its promising potential for preventing and managing periodontal disease.