Effects of herbal-based toothpastes on cell viability

Purpose: To evaluate the effects of herbal-based toothpastes with different contents on the viability of L929 cells. Methods: Herbal-based toothpastes {Aloe vera - propolis herbal toothpaste, Group 1; Parodontax, Group 2; Toothpaste with miswak, propolis and tea tree extract, Group 3, Dent natural protective toothpaste with clay, Group 4; Gano fresh, Group 5} were diluted (1:1, 1:2, 1:4, 1:8, 1:16, and 1:32) in Dulbecco's modified Eagle's medium. L929 fibroblast cells were treated with the medium containing the herbal toothpastes for 2 min. Cell viability was assessed using methyl tetrazolium test. The viability of the negative control group was set at 100 %, and the percentage viability of all groups was determined accordingly. Results: Cell viability was significantly reduced at all dilutions in Group 5 (p = 0.00). This trend was also observed in Group 4. All dilutions except 1:32 significantly affected cell viability (p = 0.00). In Group 2, only the 1:1 dilution showed a toxic effect (p = 0.00). The samples in Groups 1 and 3 did not show statistically significant cytotoxicity to L929 cells (p > 0.05). Conclusion: Herbal toothpastes containing substances such as sodium lauryl sulfate (Group 5) and sodium benzoate (Groups 2 and 4) are cytotoxic towards L929 cells. Groups 1 and 3 did not contain detergents but contain potassium sorbate as a preservative; hence, they are not toxic.