Management of dental plaque/biofilms is critical to maintain oral health. The objective of this study is to investigate the treatment effects of non-thermal atmospheric gas plasmas on oral biofilm formation and recovery under in vitro and in vivo conditions. Streptococcus mutans biofilms, a significant contributor to tooth decay, were cultured and treated by plasma. It was found that plasma treatment not only significantly reduced the in vitro biofilms, but also increased the metabolic activity of the bacteria in the biofilms. As compared with untreated control group, the cell metabolic activity, as measured by MTT assay, increased by 273%, and the aconitase activity increased by 446% for the plasma-treated group. The increased metabolic activity of the plasma-treated biofilm bacteria enhanced their susceptibility to antibiotic and host defense. An in vivo animal model using a total of 60 female rats (19 days old) were used to evaluate the anti-caries effects on the molars by 2 min of plasma treatment. It was found that, 6 months after the plasma treatment, the decayed surfaces were reduced by 62.5% on the upper molars and by 31.6% on the lower molars as compared with the untreated upper and lower molars, respectively. These in vitro and in vivo data demonstrate that the physiological state change of the biofilm due to plasma treatment provided benefit to caries control and prevention.

牙菌斑/生物膜的管理对于维持口腔健康至关重要。本研究的目的是研究在体外和体内条件下非热大气气体等离子体对口腔生物膜形成和恢复的治疗效果。变形链球菌生物膜是蛀牙的重要原因，通过血浆培养和处理。结果发现，等离子体处理不仅显着降低了体外生物膜，还增加了生物膜中细菌的代谢活性。与未处理的对照组相比，经MTT测定的细胞代谢活性增加了273%，血浆处理组的乌头酸酶活性增加了446%。等离子体处理的生物膜细菌代谢活性的增加增强了它们对抗生素和宿主防御的敏感性。的体内共使用60只雌性大鼠（19天龄）的动物模型中使用通过等离子体处理2分钟，以评估在臼齿的防龋齿效果。结果发现，等离子体处理后6个月，与未处理的上、下臼齿相比，上臼齿和下臼齿的腐烂表面分别减少了62.5%和31.6%。这些体外和体内数据表明，生物膜的由于等离子处理的生理状态变化提供益处龋齿控制和预防。