Assessing Differences between the Dentin Color and the Tooth Color

Method:  Sound natural extracted maxillary anterior teeth were used in the study. Horizontal and vertical grooves were cut into enamel to be used as a reference for the measurement locations. Teeth were mounted on a dentoform with a bite registration material (Regisil, DENTSPLY). An image of the tooth was captured with an image-based spectrophotometer (Spectroshade Micro, MHT Optic Research). The thickness of enamel for each tooth was determined with a radiograph. Enamel was grinded to expose the facial dentin with a diamond bur. Then an image of the facial dentin was captured. The color of the tooth and the dentin was compared based on the CIE LAB color space at nine locations in the incisal, middle and cervical thirds. Color difference between the whole tooth color measurement and the corresponding dentin color measurement was calculated for each tooth.

Result: 89 maxillary extracted anterior teeth were included in the study. Based on the paired-samples t-test, the data provided evidence that there was a significant difference between the color of dentin and the color of tooth (p<0.05 in each instance), except for the color parameter L measured at the incisal third (p=0.9251). For parameters L and b, the results indicated that the mean color of dentin was greater than the mean color of tooth, while it was lower for parameter a.

Conclusion: The results of this study suggest that the dentin is higher in value than the tooth. In addition, the dentin color was higher in b but lower in a than the tooth color. The difference between the color of the tooth and the dentin was the least in the cervical third.