The effect of crude extracts of nine African chewing sticks on oral anaerobes.

Chewing sticks are widely used in Nigeria for dental and oral hygiene. In-vitro susceptibility tests were done with crude extracts from nine popular sticks on four species of Bacteroides. Serindeia warneckei chewing stick had the greatest and most consistent inhibitory effect on the four species; extracts from bark and pulp were bactericidal at concentrations of less than or equal to 1%. Extracts of other sticks, when inhibitory, were only so at higher concentrations--in the range 2-30%. All the black-pigmented oral anaerobes were very susceptible to eight of the nine chewing-stick extracts but non-pigmented anaerobes showed variable susceptibilities.