IADR Abstract Archives
Additive Ions Influence Calcium Phosphate Crystallization in Enamel Remineralization.
Objectives: To explore the effect of the presence of additive F, Mg, and Zn ions on calcium phosphate crystal organization, and morphology in enamel remineralization
Methods: Human teeth were sliced in to 1.5 mm thickness and ultrasonically cleaned for 5 minutes. After demineralizing teeth slices with 5% HNO3 for 50 seconds, teeth slices were cleaned with distilled water and placed in 20 ml glass vial. Remineralization solution was prepared by mixing Tris, CaCl2, KH2PO4, NaCl, and water. The solution pH was adjust to 7.30 with HCl. After added 15 ml of remineralization solution in each vial, F, Mg, and Zn ion were added into each vial at designed different concentrations. The samples were stored at 37 C for 16 hours for remineralization. Crystal formed on enamel surface were analyzed with FE-SEM for morphology and organization. Crystal elemental composition and mineral phase were analyzed with EDS and XRD, respectively.
Results: In the presence of 52.6 mM (1 ppm) of F- in remineralization solution, the combination of plate- and needle-like structure crystals was found on enamel surface. Since the increase of F- affected size and shape of crystal, a higher concentration of F- induced smaller, rounder, and denser needle-like crystal formation. Although Mg2+ did not directly affect crystal morphology, the high concentration increased crystal density. In the presence of combined F- with Mg2+, small needle-like crystal with greater density formed. The presence of high Zn concentration inhibited the formation of crystal; crystal layers were homogenous after combined F- with low concentration of Zn2+. XRD analysis revealed that the octacalcium phosphate phase was dominated without F and Mg ions, while hydroxyapatite phase was dominated in the presence of F and Mg. The EDS elemental analysis results in Table 1 also indicated the Ca/P ratio without F and Mg ions was OCP phase, while in the presence of high concentration F and Mg it was close to HA.
Conclusions: There is a synergistic effect of F, Mg, Zn ions on HA crystallization in enamel remineralization. With a certain amount of these elements, a fine and dense needle-like crystal can formed on enamel within 16 hours.
Methods: Human teeth were sliced in to 1.5 mm thickness and ultrasonically cleaned for 5 minutes. After demineralizing teeth slices with 5% HNO3 for 50 seconds, teeth slices were cleaned with distilled water and placed in 20 ml glass vial. Remineralization solution was prepared by mixing Tris, CaCl2, KH2PO4, NaCl, and water. The solution pH was adjust to 7.30 with HCl. After added 15 ml of remineralization solution in each vial, F, Mg, and Zn ion were added into each vial at designed different concentrations. The samples were stored at 37 C for 16 hours for remineralization. Crystal formed on enamel surface were analyzed with FE-SEM for morphology and organization. Crystal elemental composition and mineral phase were analyzed with EDS and XRD, respectively.
Results: In the presence of 52.6 mM (1 ppm) of F- in remineralization solution, the combination of plate- and needle-like structure crystals was found on enamel surface. Since the increase of F- affected size and shape of crystal, a higher concentration of F- induced smaller, rounder, and denser needle-like crystal formation. Although Mg2+ did not directly affect crystal morphology, the high concentration increased crystal density. In the presence of combined F- with Mg2+, small needle-like crystal with greater density formed. The presence of high Zn concentration inhibited the formation of crystal; crystal layers were homogenous after combined F- with low concentration of Zn2+. XRD analysis revealed that the octacalcium phosphate phase was dominated without F and Mg ions, while hydroxyapatite phase was dominated in the presence of F and Mg. The EDS elemental analysis results in Table 1 also indicated the Ca/P ratio without F and Mg ions was OCP phase, while in the presence of high concentration F and Mg it was close to HA.
Conclusions: There is a synergistic effect of F, Mg, Zn ions on HA crystallization in enamel remineralization. With a certain amount of these elements, a fine and dense needle-like crystal can formed on enamel within 16 hours.
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