Evaluating the antibacterial and antibiofilm activity of Zataria multiflora in comparison with chlorhexidine, using a tooth model: A preliminary study.

Abstract

Background: The formation of biofilm on the tooth surface can lead to the dissolution of the enamel minerals and the onset of tooth decay. Natural compounds may prove to be effective in the prevention of biofilm formation.

Objectives: The present study aimed to evaluate the antibacterial and antibiofilm activity of the Zataria multiflora ethanolic extract in comparison with chlorhexidine, using a novel tooth model.

Material and methods: The study used teeth extracted due to orthodontic treatment or impacted wisdom tooth surgery. Saliva was collected from a volunteer 12 h after tooth brushing, before the test, and it was used freshly. The teeth were placed in 5 test tubes containing a broth medium and serial dilutions of the Z. multiflora extract (50, 25, 12.5, 6.25, and 3.125 mg/mL). A total of 1 mL of the collected saliva was added to each test tube. The growth of microorganisms in the medium was examined visually and the antibiofilm activity of the plant extract was assessed after 72 h, using a spatula. The results were compared with those of positive and negative controls.

Results: Considerable turbidity was observed in the positive control tube containing a tooth, the culture medium and saliva, indicating that the conditions were favorable for the growth of oral flora. No bacterial growth or biofilm formation were observed in the test tubes containing ≥25 mg/mL of the plant extract.

Conclusions: The study results indicated that the Z. multiflora extract had an excellent inhibitory effect against microorganisms and plaque formation in the tooth model, suggesting a suitable substitute for chlorhexidine. However, further studies in this area are recommended.