EFFECTS OF SMOKELESS TOBACCO PRODUCTS ON STREPTOCOCCUS MUTANS: AN IN VITRO STUDY

Objective: Tobacco use in smokeless form is one of the most prevalent forms of substance abuse worldwide.In addition to its well-established association with carcinogenesis, smokeless tobacco has been reported to influence the composition of the oral microflora.Streptococcus mutans is a key cariogenic microorganism responsible for the initiation and progression of dental caries.Understanding the interaction between smokeless tobacco products and oral bacteria is essential for evaluating their impact on oral health.The present study aimed to assess the effects of different smokeless tobacco extracts on the growth of Streptococcus mutans under controlled laboratory conditions.A Methods: pure stock culture of S. mutans was inoculated into Mueller-Hinton broth supplemented with three different concentrations of smokeless tobacco extracts, namely khaini, unprocessed tobacco leaves, zarda, pan masala, and scented tobacco.Following incubation, bacterial growth was quantified by subculturing onto Mueller-Hinton agar plates and determining the colony-forming units (CFU).The antimicrobial activity of each extract was further evaluated using the agar diffusion method, and the zones of inhibition were measured to assess bacterial growth suppression.Results: The CFU counts revealed a concentration-dependent reduction in S. mutans growth across all smokeless tobacco extracts, with higher concentrations exhibiting greater inhibitory effects.The zone of inhibition was most pronounced with pan masala at 700 µg and unprocessed tobacco leaves at 1200 µg, compared to khaini (1800 µg), zarda (2100 µg), and scented tobacco (1250 µg).Smokeless tobacco extracts negatively influence the growth of Conclusion: Streptococcus mutans in a dose-dependent manner, indicating a potential antimicrobial effect on cariogenic bacteria.