PURPOSE: This work aims to study the erosion on restorative materials and on surrounding dentin. Fifty root dentin samples were obtained from bovine incisors. METHODS: Twenty samples were not restored and thirty received cavity preparations. Samples were assigned to five groups: G1, G2: sound dentin (D); G3: composite resin (CR); G4: resin-modified glass-ionomer cement (RMGIC); G5: glass-ionomer cement (GIC). The samples of groups 2-5 were submitted to six cycles (demineralization-remineralization). Samples were analyzed by micro energy-dispersive X-ray fluorescence spectrometry (μ-EDXRF) and by scanning electron microscopy (SEM). RESULTS: Mineral loss was greater in G2 samples than in RMGI > CR > GIC > D (control). SEM images showed pronounced dentin demineralization in groups 2 and 4. The acid erosion has a significant effect on mineral loss (Ca and P) of root dentin without restoration. CONCLUSIONS: Composite resin had the best chemical resistance to erosion among all the materials. Fluoride contained in GIC seemed to cause some protection, however, with material degradation. Chemical interaction of tooth-colored dental materials with root dentin could be assessed by μ-EDXRF.
PURPOSE: This work aims to study the erosion on restorative materials and on surrounding dentin. Fifty root dentin samples were obtained from bovine incisors. METHODS: Twenty samples were not restored and thirty received cavity preparations. Samples were assigned to five groups: G1, G2: sound dentin (D); G3: composite resin (CR); G4: resin-modified glass-ionomer cement (RMGIC); G5: glass-ionomer cement (GIC). The samples of groups 2-5 were submitted to six cycles (demineralization-remineralization). Samples were analyzed by micro energy-dispersive X-ray fluorescence spectrometry (μ-EDXRF) and by scanning electron microscopy (SEM). RESULTS: Mineral loss was greater in G2 samples than in RMGI > CR > GIC > D (control). SEM images showed pronounced dentin demineralization in groups 2 and 4. The acid erosion has a significant effect on mineral loss (Ca and P) of root dentin without restoration. CONCLUSIONS: Composite resin had the best chemical resistance to erosion among all the materials. Fluoride contained in GIC seemed to cause some protection, however, with material degradation. Chemical interaction of tooth-colored dental materials with root dentin could be assessed by μ-EDXRF.