Intraoral treatment of persimmon tannin, a polyphenol extracted from persimmon, significantly ameliorates gingivitis, plaque and halitosis via directly influence the periodontal bacteria Porphyromonas gulae

BACKGROUND: As periodontal disease (PD) is an irreversible disorder, preventive dentistry in human and veterinary medicine has become pertinent. This study focused on persimmon tannin (PT) and examined its bactericidal, anti-halitosis, and anti-inflammatory effects by focusing on Porphyromonas gulae (P. gulae). METHODS: The direct effects of PT on P. gulae were evaluated in vitro. Pro-inflammatory cytokines secretion induced by P. gulae in the macrophage cell lines were determined. A clinical study in dogs with P. gulae-associated PD was performed by one-month intraoral treatment with 0.1% PT-containing gel. RESULTS: PT exhibited a significant bactericidal effect to P. gulae. The biofilm formation and methyl mercaptan generated by P. gulae was significantly decreased by PT even after a short exposure period. P. gulae-induced proinflammatory cytokine production in macrophage cell lines was inhibited by PT treatment in a dose-dependent manner. In a clinical study of dogs, intraoral treatment with 0.1% PT did not significantly influence the gingivitis and plaque scores, however, the concentrations of hydrogen sulfide and methyl mercaptan were also significantly decreased by the PT treatment. Although there was no anti-bacterial in vitro, P. gulae activity and DNA detection decreased with PT treatment. CONCLUSIONS: These findings suggest that intraoral administration of PT can prevent PD.