Incorporating copper into fluoride-containing bioglasses enhances the inhibition of Streptococcus mutans activity and biofilm formation

AbstractLow fluoride-containing bioglasses (LFBGs) with the ability to controllably degrade and form acid-resistant fluorapatite are attractive for caries prevention. However, their antibacterial effect is not satisfactory. To address this problem, we first time incorporated copper (0-5 mol%) into LFBG (1 mol% CaF2) by a melt-quench method. Then, we investigated the effects of copper addition on the glass structure, bioactivity, cytocompatibility, inhibitory performance againstStreptococcus mutansand the potential antibacterial mechanism of glasses. The results revealed that copper was not bound directly to fluoride or orthophosphate and might be present as Si-O-Cu2+. Glasses with the proper copper content (≤ 2 mol%) were cytocompatible. All of the Cu-doped LFBGs (FCuBGs) exhibited high bioactivity and excellent antibacterial properties with increasing copper content. Moreover, we present the first detailed analysis of the potential antibacterial mechanism of FCuBGs, which are attractive for dental applications, including use as fissure sealers, varnishes, and additives for caries prevention.