Antimicrobial Effect of Non-Thermal Atmospheric Plasma on Streptococcus Mutans -The Key Cariogenic Microorganism in Plaque Biofilm
Background: To evaluate the antimicrobial effect of non-thermal atmospheric plasma on mutans biofilms.
Materials: A 100 µl culture of Streptococcus mutans poured into two 120 well flat base microtiter plates, allowed to adhere and incubated overnight using brain heart infusion (BHI). These 120 wells were grouped into four groups, group A-helium treated, group B-plasma treated, group C- chlorohexidine treated and group D-control group (untreated group) with a group size of 30 wells per group. Triphenyl tetrazolium chloride (TTC) essay & Colony Forming Units (CFU) counting was done to check the viability & survival of streptococcus mutans biofilms.
Results: The results showed that there was a significant difference in the mean optical density (OD) among the four groups (p<0.001). Post-hoc analysis revealed that untreated samples and Helium had significantly higher mean OD than plasma and chlorhexidine groups. A similar result was also seen using the survival essay by CFU counting. Conclusion: Plasma utilizes the air from the atmosphere, thus rendering plasma a better reach in the oral cavity. This property of plasma can be efficiently used to neutralize Streptococcus mutans biofilms in the oral cavity.
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