[ Abstract] Objective To study the fitness of color dimension between Vitapan 3D-Master shade guides and nature teeth. Methods 2 159 nature teeth from Nanjing population and Vitapan 3D -Master shade guides were analyzed by dental chromameter ShadeEye NCC on CIE L*a*b* color system. Results 1）The color dimension of natural teeth displayed a broader range than those from Vitapan 3D-Master shade guides. Comparing with incisor group, canine -premolar group had better fitness with Vitapan 3D-Master shade guides. 2）In color space, incisor values a* shifted toward green（-a*）, while the shade guide values a* located toward red（+a*）. The shade guide lacked tabs of values L* 71—78 and a* -1.5—-0.2 for natural incisor. 3）According to the perceptibility threshold △E*ab
