Influence of different pulp capping materials to induce coronal tooth discoloration

Aim: This study aimed to evaluate the influence of white MTA, gray MTA, calcium hydroxide and calcium aluminate cement (CAC) in tooth color when used as pulp capping materials. Methodology: Extracted third molars were used (n = 50). According to the experimental groups, a 2 mm layer was placed in the pulp canal chamber: Group 1 — White MTA; Group 2 — Gray MTA; Group 3 — CAC; Group 4 — calcium hydroxide paste followed by calcium hydroxide cement. In the control group white gutta-percha was used. Vestibular, lingual, mesial and distal color readout was performed at baseline and after 30 days. Images were captured using a digital camera Nikon D80 and shade evaluation performed using Photoshop 7.0. The blue channel in red, green and blue color mode (RGB) was used to measure chromatic changes in a scale from 0 (darkest) to 255 (lightest). The data were evaluated by univariate analysis. Results: All teeth showed some discoloration after 30 days. The mean variation of pixel intensity for the blue channel was similar between groups. However, considering the mean pixel intensity for the blue channel after 30 days, teeth where CAC was used were significantly darker than those from the control group. Conclusions: This study demonstrated that all tested materials induced teeth shade changes after 30 days of simulated pulpotomy. The mean variation of color was similar between groups and CAC caused the higher color change.