Streptococcus mutans is considered to be a major bacterium involved in dental caries, and the control of virulence mechanisms is fundamental to prevent disease. Probiotics present a promising preventive method; however, the use of probiotics requires its incorporation into delivery materials to facilitate oral colonization. Thus, we performed a comprehensive study examining preventive effects of Lactobacillus paracasei 28.4–enriched gellan hydrogel materials to inhibit S. mutans in planktonic and biofilm states, addressing its influence in the production of extracellular polysaccharides (EPS) and altered gene expression of several cariogenic virulence factors. L. paracasei 28.4, a strain isolated from the oral cavity of a caries-free individual, was incorporated in three gellan hydrogels (0.5%, 0.75%, and 1% w/v). The pretreatment with probiotic-gellan formulations provided a release of L. paracasei cells over 24 h that was sufficient to inhibit the planktonic growth of S. mutans, independent of the gellan concentrations and pH variations. This pretreatment also had inhibitory activity against S. mutans biofilms, exhibiting a reduction of 0.57 to 1.54 log₁₀ in CFU/mL (p < 0.0001) and a decrease of 68.8 to 71.3% in total biomass (p < 0.0001) compared with the control group. These inhibitory effects were associated with the decreased production of EPS by 80% (p < 0.0001) and the downregulation of luxS, brpA, gbpB, and gtfB genes. The gellan formulation containing L. paracasei 28.4 exhibited probiotic effects for preventing S. mutans growth, biofilm formation, and production of cariogenic factors to suggest possible use in tooth decay prevention.

变形链球菌被认为是涉及龋齿的主要细菌，控制毒力机制是预防疾病的基础。益生菌是一种很有前途的预防方法；然而，益生菌的使用需要将其掺入递送材料中以促进口腔定植。因此，我们进行了一项综合研究，检查富含副干酪乳杆菌28.4 的结冷胶水凝胶材料对抑制S 的预防作用。浮游和生物膜状态的变形菌，解决其对胞外多糖 (EPS) 产生的影响和几种致龋毒力因子基因表达的改变。升。副干酪28.4，一种从无龋个体口腔中分离出来的菌株，被掺入三种结冷胶水凝胶（0.5%、0.75% 和 1% w/v）中。益生菌-结冷胶制剂的预处理提供了L的释放。副干酪细胞超过 24 小时足以抑制S的浮游生长。mutans，与结冷胶浓度和 pH 值变化无关。这种预处理对S也具有抑制活性。mutans生物膜，CFU/mL ( p  < 0.0001)减少 0.57 至 1.54 log ₁₀，总生物量减少 68.8% 至 71.3% ( p < 0.0001) 与对照组相比。这些抑制作用与 EPS 产量减少 80% ( p  < 0.0001) 和luxS、brpA、gbpB和gtfB基因的下调有关。含有L的结冷胶配方。paracasei 28.4 表现出预防S 的益生菌作用。变形菌的生长、生物膜形成和致龋因子的产生表明可能用于预防蛀牙。