Asian Journal of Dental Sciences

Aim: This study aimed to assess the antimicrobial potential of Azadirachta indica (neem) plant extracts on Streptococcus mutans, a key bacterium associated with dental caries.

Methods: Neem plant parts (leaves, twigs, and stem bark) were collected from Ibadan, Oyo State, Nigeria, and identified at the Herbarium unit, University of Ibadan. Ethanol and aqueous extracts were prepared using standard procedures. Media including Brain-heart infusion broth, Nutrient agar, Blood agar, Mac Conkey agar, and GSTB medium were used for bacterial culture. Antibiotic susceptibility testing was conducted using Bacitracin and Sodium telluride. The study focused on the isolation and identification of Streptococcus mutans from oral specimens, bacterial counts, and the antimicrobial sensitivity profile of neem extracts using the agar well diffusion method.

Results: The study revealed the absence of Streptococcus mutans in some specimens. Staphylococcus sp. and total bacterial counts varied among the samples. The frequency of occurrence of Streptococcus mutans, Staphylococcus aureus, and Staphylococcus epidermidis was documented. The antimicrobial sensitivity profile demonstrated varied zones of inhibition in response to neem extracts against Streptococcus mutans strains.

Conclusion: Neem extracts exhibited antimicrobial activity against Streptococcus mutans, suggesting their potential role in combating dental caries. The study contributes valuable insights into the therapeutic properties of neem in oral health, paving the way for further research and potential applications in dentistry.