Cannabis beverages pose surprising risks to tooth enamel

To evaluate the erosive potential of commercially available cannabis beverages by assessing fluoride content and pH, as well as changes in microhardness and surface roughness. Sixteen cannabis-infused beverages were analyzed, with distilled water used as the control. Fluoride concentration and pH were measured using a fluoride ion-selective electrode and a calibrated pH meter. Eighty-five synthetic enamel-like hydroxyapatite blocks (5 mm diameter × 5 mm thickness) were prepared and allocated into 16 experimental groups and 1 control group (n = 5/group). Specimens were immersed in 5 mL of each beverage for 30 min at 37°C. Knoop microhardness (KHN) and surface roughness (Ra) were measured before and after immersion. The percentage of surface hardness loss (%SHL) and percentage change in surface roughness (%Raalt) were calculated. Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test (p < 0.05). Most beverages exhibited acidic pH values, with 12 samples showing pH < 4. Fluoride concentrations ranged from 0.0268 to 1.8233 mg/L, with most samples containing levels insufficient to counteract erosive effects, although one beverage exceeded recommended fluoride limits. Beverages with lower pH were associated with significant reductions in microhardness and increases in surface roughness (p < 0.05). The percentage of surface hardness loss (%SHL) ranged from approximately 27% to 74% among acidic beverages, with the highest values observed in the most acidic formulations. In contrast, beverages with near-neutral pH showed minimal changes, with %SHL below 10%. Similarly, %Raalt ranged from less than 10% in low-erosive groups to over 900% in highly acidic beverages. Cannabis beverages with low pH exhibited significant erosive potential, as evidenced by decreased microhardness and increased surface roughness on synthetic enamel-like hydroxyapatite substrates. Beverage acidity and formulation were key determinants of these effects.