A study published today in Clinical Oral Investigations found that a cannabidiol-based mouthwash may help control dental biofilm without damaging enamel, suggesting CBD could serve as a potential alternative to chlorhexidine in certain oral care products.

The study was conducted by researchers from the University of São Paulo and the Federal University of Uberlândia.

Researchers evaluated experimental mouthwashes containing CBD at concentrations of 0.01%, 0.05% and 0.1%, comparing them with a placebo and a 0.12% chlorhexidine mouthwash. Chlorhexidine is widely considered a gold standard in dentistry for controlling oral bacteria, but long-term use has been linked to side effects such as staining, taste changes, dry mouth and oral irritation.

For the study, bovine enamel fragments were mounted in intraoral appliances worn by 14 participants in a double-blind crossover design. Each treatment phase lasted seven days, with washout periods between phases. One side of the appliance was exposed to a 20% sucrose solution to create a cariogenic challenge before treatment.

Researchers measured surface roughness, microhardness, color change, biofilm formation and yeast counts. They also analyzed enamel surfaces using scanning electron microscopy.

According to the study, CBD at 0.05% showed the strongest overall potential, demonstrating biofilm control similar to chlorhexidine without negatively affecting enamel properties. CBD at 0.05% and 0.1% performed similarly to chlorhexidine in reducing biofilm accumulation and maintaining enamel microhardness.

However, the researchers noted that CBD 0.1% showed higher surface roughness than chlorhexidine under sucrose exposure, while chlorhexidine remained more effective than some CBD formulations in reducing yeast counts.

The study also found that chlorhexidine produced the highest enamel color changes, consistent with its known association with dental staining. CBD-based mouthwashes, particularly at lower concentrations, maintained color values closer to acceptable thresholds.

“CBD 0.05% demonstrated potential for biofilm control without adversely affecting enamel properties,” the researchers concluded.

The authors said the findings support further investigation into natural compound-based mouthwashes, while noting that future studies should include larger sample sizes and additional analysis of biofilm structure and composition.