Purpose: This study aimed to assess the efficacy of three techniques for preventing dental erosion and thereby identify effective methods. The three techniques were: 1) adding calcium to fermented milk (2% Ca and 0.5% Ca); 2) topical application of fluoride to the teeth before exposure to fermented milk (acidulated phosphate fluoride [APF] gel and 0.05% NaF); and 3) a combination of the two techniques (APF gel + 0.5% Ca, 0.05% NaF + 0.5% Ca).
Materials and Methods: pH cycling was performed on bovine-tooth specimens alternately immersed in experimental solutions and artificial saliva. After treatment, the microhardness and roughness of the enamel surfaces were measured, and changes in the surface morphology were observed using atomic force microscope images.
Results: Microhardness did not differ statistically significantly between the 2% Ca and mineral water (negative control) groups (2% Ca: 295.34 ± 11.50; mineral water group: 294.76 ± 10.67; p > 0.05). Surface roughness did not differ statistically significantly between the 2% Ca, 0.05% NaF + 0.5% Ca, and mineral water groups (2% Ca: 16.81 ± 7.23; 0.05% NaF + 0.5% Ca: 15.77 ± 2.86; mineral water group: 13.35 ± 5.53; p > 0.05). The surface morphology did not change in the mineral water and 2% Ca groups.
Conclusion: Considering that 2% calcium is a high concentration, adding a low concentration of calcium to fermented milk and applying a low concentration of fluoride daily decreased the reduction of surface microhardness and reduced the increase in surface roughness without causing marked changes in surface morphology. This confirms that combining the two techniques is an effective strategy to prevent dental erosion in-vitro.