Research on color differences between enamel and dentin of natural teeth / 第二军医大学学报

ABSTRACT

Objective To investigate the color differences of enamel and dentin of natural teeth, so as to lay a foundation for reducing the color differences of natural dentin and core of all ceramic restorations. Methods X-rite Color i7 Spectrophotometer was used to examine the chroma value and chromatic difference (δE) of enamel and dentin of natural teeth (thickness 0. 9 mm, 0. 6 mm and 0. 3 mm, n = 30). Results The L* values (lightness) of enamel and dentin increased with the decrease of slice thickness, and the a* values (red-green) and b* values (yellow-blue) decreased with the decrease of slice thickness (P<0. 05). The absolute L*, a* and b* values of the dentin were significantly greater than those of enamel of same thickness (P<0. 05). There were great color differences between enamel and dentin of different thicknesses, with the mean δE values within a range of 5. 303-13. 109. The color difference gradually increased with the thickness increase of enamel and dentin. The δE value of the enamel and dentin of the same thickness was 5. 115 (0. 9 mm), 5. 855 (0. 6 mm), and 6. 053 (0. 3 mm), respectively. Conclusion There is noticeable color difference between the enamel and dentin of natural teeth, and the difference increases with the increase of their thickness difference. The dentin has a more yellowish color and less lightness compared with the enamel. So each laminate of all ceramic restorations needs a shade selection for all ceramic restorations, and more attention should be paid on the color matching of natural dentin and core ceramic laminate.