Jiankang He1, Yijun Bao1, Jie Li1, Zhongjun Qiu2, Ying Liu3, Xu Zhang4. 1. School of Stomatology, Hospital of Stomatology, Tianjin Medical University, 12 Observatory Road, Tianjin, 300070, China. 2. State Key Laboratory of Precision Measuring Technology & Instruments, Tianjin University, Tianjin, 300072, China. 3. School of Stomatology, Hospital of Stomatology, Tianjin Medical University, 12 Observatory Road, Tianjin, 300070, China. Electronic address: yingliu04@tmu.edu.cn. 4. School of Stomatology, Hospital of Stomatology, Tianjin Medical University, 12 Observatory Road, Tianjin, 300070, China. Electronic address: zhangxu@tmu.edu.cn.
Abstract
OBJECTIVES: This study investigated the effect of CMC/ACP on oral bacteria adherence and biofilm formation on the enamel surface as well as the underlying mechanism to determine the anti-cariogenic potential of CMC/ACP. METHODS: A mineral solution of CMC/ACP was characterised by transmission electron microscope. The bactericidal activity of CMC/ACP was evaluated with the plate count method. An in vitro biofilm model was established on saliva-coated enamel blocks; the effect of CMC/ACP on the adherence of Streptococcus mutans and Streptococcus gordonii to and biofilm formation on these blocks, as well as co-aggregation of Fusobacterium nucleatum was assessed by scanning electron microscopy, crystal violet staining, and confocal microscopy. Bacterial surface charge was estimated with the cytochrome c binding assay and by zeta potential measurement. RESULTS: CMC/ACP nanocomplexes inhibited S. mutans and S. gordonii adherence to enamel blocks by 90% and 86% (P < 0.01), respectively, and biofilm formation by 45% and 44% (P < 0.01), respectively, after 24 h without bactericidal activity. CMC/ACP reduced F. nucleatum attachment to streptococcal biofilm by 75% (P < 0.01) while also altering cytochrome c binding to bacteria and reducing the zeta potential of the bacterial suspension. CONCLUSIONS: CMC/ACP nanocomplexes inhibit cariogenic bacterial adherence, co-adhesion, and biofilm formation on the enamel surface, possibly by altering bacterial surface charge and enhancing the flocculation effect. As an agent that promotes remineralisation and has anti-cariogenic effects, CMC/ACP can be used to prevent and treat early caries and white spot lesions.
OBJECTIVES: This study investigated the effect of CMC/ACP on oral bacteria adherence and biofilm formation on the enamel surface as well as the underlying mechanism to determine the anti-cariogenic potential of CMC/ACP. METHODS: A mineral solution of CMC/ACP was characterised by transmission electron microscope. The bactericidal activity of CMC/ACP was evaluated with the plate count method. An in vitro biofilm model was established on saliva-coated enamel blocks; the effect of CMC/ACP on the adherence of Streptococcus mutans and Streptococcus gordonii to and biofilm formation on these blocks, as well as co-aggregation of Fusobacterium nucleatum was assessed by scanning electron microscopy, crystal violet staining, and confocal microscopy. Bacterial surface charge was estimated with the cytochrome c binding assay and by zeta potential measurement. RESULTS: CMC/ACP nanocomplexes inhibited S. mutans and S. gordonii adherence to enamel blocks by 90% and 86% (P < 0.01), respectively, and biofilm formation by 45% and 44% (P < 0.01), respectively, after 24 h without bactericidal activity. CMC/ACP reduced F. nucleatum attachment to streptococcal biofilm by 75% (P < 0.01) while also altering cytochrome c binding to bacteria and reducing the zeta potential of the bacterial suspension. CONCLUSIONS: CMC/ACP nanocomplexes inhibit cariogenic bacterial adherence, co-adhesion, and biofilm formation on the enamel surface, possibly by altering bacterial surface charge and enhancing the flocculation effect. As an agent that promotes remineralisation and has anti-cariogenic effects, CMC/ACP can be used to prevent and treat early caries and white spot lesions.