Protective effects of resin sealant and flowable composite coatings against erosive and abrasive wear of dental hard tissues

ObjectivesTo test the effectiveness of sealant and flowable composite coating on eroded enamel, dentin and cementum under erosive/abrasive challenges in vitro.MethodsA total of 108 tissue sections (36 each for enamel, dentin and cementum) from third molars were assigned to three groups: Seal & Protect sealant (S&P), Tetric EvoFlow composite (TEF) and control. Erosive/abrasive lesions were created on each specimen by citric acid and brushing with toothpaste. S&P and TEF were applied to the lesions and subjected to erosive/abrasive cycling included 24 cycles of immersion in citric acid (pH 3.6) for 60 min, followed by remineralization for 120 min and brushing with toothpastes for 600 strokes at 150 g. Erosive wear of materials or dental tissues were measured with 3D scanning microscopy and data were analyzed using ANOVA.ResultsTreatments with S&P and TEF created a protective material coating of 42.7 ± 17.8 μm and 150.8 ± 9.9 μm in thickness, respectively. After 24 cycles of erosive/abrasive challenges, tissue losses were −346.9 ± 37.3 μm for enamel, −166.5 ± 26.3 μm for dentin and −164.7 ± 18.2 μm for cementum in untreated controls, as compared to material losses of −24.4 ± 3.3 μm for S&P, and −10.8 ± 4.4 μm for TEF, respectively. Both S&P and TEF were effective in protecting enamel, dentin and cementum against erosive tooth wear (p < 0.01). S&P exhibited faster wear than TEF (p < 0.01) and showed spotted peeling in a third of the specimens. TEF remained intact on all three types of dental tissues at the end of the 24 cycles of erosive/abrasive challenges.ConclusionsA thin coating of flowable composite resin 150 μm in thickness may provide long-term protection against erosive/abrasive tooth wear. Resin sealant may provide adequate protection for dental hard tissues in short-term and may require repeated applications if long-term protection is desired.