Ethnomedical aspects of the commonly used toothbrush sticks in Ethiopia.

Objective: To determine the botanical identity, cytotoxicity, and antibacterial property of the commonly used toothbrush sticks in Ethiopia.
Setting: Research laboratories of the departments of Biology and Chemistry, Addis Ababa University between December 1993 and May 1995.
Methods: The study was performed by purchasing the commonly used toothbrush sticks from street markets in various towns of Ethiopia. Voucher specimens were collected and their botanical identity was determined following floral keys. The toothbrush sticks were ground in a mill and soaked in absolute methanol for 24 hours and filtered. The filtrates were dried in a rotary evaporator and the crude extracts were stored at 4 degrees C. The crude methanol extracts were used to test their antibacterial activity by impregnating into filter paper discs and placing on test plates of Staphylococcus aureus and Bacillus cerues. Their lethality to brine shrimp (Artemia salina) was performed following standard procedures.
Results: Twenty different species of plant used as toothbrush were collected and their botanical identity determined. Crude methanol extracts of only Agave sisalana, Birbira and Hypericum revolutum test concentrations up to 500 micrograms/ml showed weak toxicity to brine shrimp. All the extracts showed antibacterial activity against Staphylococcus aureus and Bacillus cereus by agar diffusion method.
Conclusion: Toothbrush sticks can be used by the vast majority of people who cannot afford buying the commercial toothbrush and toothpaste. The toothbrush sticks may be important for the oral and dental hygiene of the users and hence may be useful in decreasing dental caries. Further studies should focus on the effect of the toothbrush sticks against other common bacteria that are associated with dental diseases.