Objective To evaluate the in vitro antibacterial activity of Arthodont against Porphytomonas gingivalis （P.gingivalis）, Haemophilus actinomycetemcomitans（H.actinomycetemcomitans） and Fusobacterium nucleatum（F.nucleatum）. Methods Broth dilution method was used to detect the minimum inhibitory concentration（MIC）and the minimum bactericidal concentration（MBC） of Arthrodont against P.gingivalis, H.actinomycetemcomitans and F.nucleatum. Results All pathogens were inhibited by Arthrodont. For H.actinomycetemcomitans, the antibacterial activity of toothpaste were strongest of the three, the MIC and MBC were both 0.8 g·L－1. The MIC and MBC of Arthrodont against P.gingivalis were 3.12 g·L－1 and 12.5 g·L－1, against F.nucleatum were 6.25 g·L－1 and 25 g·L－1. Conclusion Arthrodont has strong antibacterial activity against the periodontal suspected pathogens.
