Tooth Shade Matching; Visual vs. Digital Camera Method

Objectives: To compare the tooth shade matching ability of dental professionals using simple visual method versus digital camera assisted method
Methods: Sixteen tooth shade tabs from Vita Classic shade guide were taken. An Ultra compact digital camera was used to acquire the images at uniform settings. Three images of each tab were taken at a pre-set object-camera distance. This step generated 144 reference images. For establishing test tabs, we used six masked tabs (assessor blinded) and used the above mentioned procedure to acquire a set of 18 test images.
The two set of images (reference & test) were imported in the Photoshop software. An area of body of each tab image was selected, averaged and color parameters (hue, chroma & value) were determined. Using CIE L c*h* formula, the color difference of each test tab with each reference image at given distance were determined. Participants were asked to match the tooth shade. The outcome was correct match versus incorrect match using the two methods. SPSS 19.0 was used for the data analysis
Results: Digital method yielded overall correct colour match in 66% samples compared to visual method that yielded 40% correct match. Dentists identified correct colour in 22% of samples while assistants correctly identified 60% samples
Conclusions: Digital colour matching was found to be superior to the visual method. Dental assistants exhibited better colour matching skills than the dentists.