Repeatability of color measurement of 3D shade guide with spectrophotometer

Objective To examine the repeatability of color measurement of Vita 3D-Master shade guide with MINOLTA CM-700d/600d portable spectrophotometer.Methods The chromatic values of incisal site and cervical site of every piece of the shade guide were measured for three times,the first time it was measured in one day,and the second and third time was respectively measured in the next day. Each measurement of the third time was taken just after the second time before the instrument was moved. All the data were calculated and analysized.Results Compared with each other separately in the three groups,the mean ΔE was smaller than 1.5NBS.Conclusion The repeatability of MINOLTA CM-700d/600d spectrophotometer is very good. And it could satisfy the demands of repeated color measurement.