Novel dipotassium oxalate-containing mouth rinses for the prevention of erosive tooth wear.

Objectives to formulate experimental solutions, simulating mouthrinses, containing 1.4% dipotassium oxalate (OXP) alone, with 225 ppm F⁻ (from NaF), or with 225 ppm F⁻ and 800 ppm Sn²⁺ (from SnCl₂), and to assess their anti-erosive effect on enamel and dentin.Methods bovine enamel and dentin specimens were randomly distributed into 6 groups (n=10/substrate): 1. Distilled water (DIW); 2. F; 3. F+Sn; 4. OXP; 5. OXP+F; 6. OXP+F+Sn. The specimens were submitted to a 5-day erosive-abrasive cycling with 1% citric acid (2 min, pH ∼ 2,4), followed by 60 minutes artificial saliva (4x/day), brushing with a standard fluoride toothpaste (2x/day) and 1 minute immersion in test solutions after each brushing episode. Surface loss (SL, in µm) was measured with an optical profilometer. Additional analyses included the determination of potentially available fluoride in the solutions and scanning electron microscopy of the specimen surfaces. Data were statistically analyzed (α=0.05).Results OXP+F+Sn showed the lowest SL in enamel and dentin (3.10 ± 1.12 and 3.27 ± 1.27, respectively), differing from F+Sn in dentin (6.24 ± 0.53; p<0.05). In enamel, F+Sn and OXP+F+Sn significantly reduced SL compared with DIW (10.31 ± 0.99; p<0.05). OXP only showed lower SL for dentin compared with DIW (3.71 ± 1.16; p<0.05). Fluoride availability matched the added concentration, with slight reduction in OXP groups. Calcium oxalate crystals were observed in OXP groups micrographs.Conclusion OXP reduced enamel and dentin surface loss, with a more pronounced effect in dentin, suggesting its potential as protective agent against erosive tooth wear.