Comparative Efficacy of Three Common Nigerian Chewing Sticks Against Oral Streptococcus mutans: An In Vitro Study

Dental caries driven by Streptococcus mutans remains a significant oral health problem across Nigerian communities, where chewing sticks from various plant sources have been used for centuries as natural oral hygiene tools. This study comparatively evaluates the in vitro antibacterial efficacy of aqueous and methanol extracts from the chewing stick species Azadirachta indica, Massularia acuminata, and Garcinia kola against clinical isolates of Streptococcus mutans. Plant materials were sourced from markets in Abeokuta, Ogun State, and extracted by cold maceration. S. mutans isolates were obtained from dental plaque samples of patients attending the dental clinic of Olabisi Onabanjo University Teaching Hospital. Antibacterial activity was evaluated by agar diffusion and minimum inhibitory concentration assays. Phytochemical screening of all three extracts detected tannins, flavonoids, alkaloids, and phenolic acids. Massularia acuminata methanol extract exhibited the highest activity against S. mutans with an MIC of 3.125 mg/mL, followed by Garcinia kola at 6.25 mg/mL and Azadirachta indica at 12.5 mg/mL. All three species demonstrated statistically superior inhibitory activity compared to a chlorhexidine-free negative control. These results provide comparative data for the scientific ranking of commonly used chewing sticks and support evidence-based promotion of Massularia acuminata and Garcinia kola for oral health applications. Keywords: chewing sticks, Streptococcus mutans, Massularia acuminata, antibacterial, oral health