Comparative effects of fluoride-containing and remineralization-promoting agents on artificial gastric juice-induced bovine enamel erosion susceptibility: an in vitro study.

BACKGROUND: Gastroesophageal reflux disease (GERD) is a major risk factor for erosive tooth wear because repeated exposure of enamel to gastric acid promotes demineralization. This in vitro study evaluated the protective effects of fluoride-containing and remineralization-promoting agents on enamel erosion induced by simulated gastric acid challenge. METHODS: Eighty-four bovine enamel specimens were randomly assigned to seven groups (n = 12/group): a sound enamel control group, an erosion control group treated with distilled water, and five treatment groups receiving Natural-F gel (2.09% NaF, NF), Tooth Mousse (fluoride-free CPP-ACP, CA), MI Varnish (5% NaF, MV), V-Varnish (5% NaF, VV), or Fluor Protector (0.1% fluoride, FP). Of the 12 specimens in each group, 10 were used for quantitative analyses and 2 for scanning electron microscopy (SEM). All groups except the sound enamel control underwent 5 days of erosive cycling with hydrochloric acid (pH 2.3) and artificial saliva. Enamel surface changes were assessed by surface roughness, gloss, microhardness, quantitative light-induced fluorescence (QLF), and SEM. RESULTS: Significant intergroup differences were observed in surface roughness, gloss, and microhardness. FP showed lower roughness and higher gloss than the other treatment groups, whereas microhardness decreased significantly in all groups except FP compared with sound enamel (p 0.05). SEM revealed rough and porous surfaces in all groups except FP, which showed a relatively smooth morphology. CONCLUSIONS: Tested fluoride-containing and remineralization-promoting agents did not provide equivalent protection against artificial gastric juice-induced enamel erosion. Although FP showed favorable effects across several enamel surface parameters, this pattern was not consistently observed across all outcome measures, particularly QLF. These findings suggest that formulation-related properties may be relevant to the design of preventive strategies for GERD-associated dental erosion.