Maxillary extracted premolars (n = 144) were sectioned and the crowns were separated from the roots. Pulp chambers were prepared to a standard size and then the tested materials (GMTA Angelus, ProRoot WMTA, Biodentine, TheraCal, and TotalFill) were placed with saline or with blood. Color change was assessed by spectrophotometry; prior to and after material placement at different time intervals of 24 h, 1 week, 1 month, 3 months, and 6 months. Color change (ΔE) values were calculated and statistically analyzed.
In the saline groups, Biodentine caused the least color change, while GMTA and WMTA caused the highest color change which were significantly different from the others (p < 0.001), TotalFill and TheraCal caused moderate changes. Adding blood increased the ΔE overall the tested materials to various degrees. Biodentine was the most affected by the blood, while MTA groups were the least affected, followed by TotalFill and then TheraCal. The increase in ΔE was significant over time up to 3 months, after which the increase was not significant.
Overall, WMTA and GMTA caused the most severe discoloration. In saline, Biodentine caused the least discoloration, but it was the most affected by the presence of blood, although it still caused the least discoloration similar to that observed with TotatFill. TheraCal caused moderate discoloration but more than that caused by Biodentine and TotalFill.