Isolation, identification, and molecular characterization of Streptococcus mutans and Enterococcus faecalis from dental caries.

Dental caries is a major global health concern, particularly among children and adolescents, significantly impacting overall health and quality of life. This study isolated 83 bacterial strains from severe dental caries cases (Streptococcus mutans, n = 59; Enterococcus faecalis, n = 24). Antibiotic susceptibility testing revealed high resistance to gentamicin (100%) and erythromycin (65-70%), with consistent sensitivity to penicillin, tetracycline, vancomycin, and clindamycin. Postbiotic extracts derived from Limosilactobacillus plantarum GD29 demonstrated dose-dependent inhibition of S. mutans biofilm formation, achieving a maximum reduction of 78% at 50% (v/v) concentration. These findings provide strong quantitative evidence supporting the potential of postbiotics as alternative therapeutic agents for managing cariogenic biofilms. The study underscores the urgent need for targeted antimicrobial strategies to combat antibiotic resistance. Importantly, this research aligns with the Good Health and Well-being by promoting innovative approaches to oral healthcare, through the development of sustainable, non-antibiotic therapeutic alternatives.