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Some negative features of MTA, such as the high incidence of dental structures staining justify the development of new materials. GMTA, WMTA, and EB with and without radiopacifying agent displayed color alteration (ΔE) after 360 days; however, the luminosity change (ΔL) was lower in EB in comparison with GMTA and WMTA.

Objectives To assess the discoloration of teeth treated with the different phases of calcium aluminate cement (CAC), in comparison with the conventional CAC and mineral trioxide aggregate (MTA). Materials and methods Fifty bovine incisors were prepared and filled. Two millimeters of the filling was removed to fabricate a cervical plug with the following cements (n=10): CA(CaO.Al2O3); CA2(CaO.2Al2O3); C12A7(12CaO.7Al2O3); CAC and MTA. The initial color measurement was performed and after 7, 15, 30, 45, 90, 180, and 365 days new color measurements were performed to determine the color (ΔE00), lightness (ΔL'), chroma (ΔC'), hue differences (ΔH'), and the whiteness index (WID). Results ΔE00 was significant for groups (p = 0.036) and periods (p < 0.05). The greater ΔE00 was observed after 365 days for CAC (12.8). C12A7 (7.2) had the smallest ΔE00. ΔL' and ΔC' were significant for groups and periods (p < 0.05). ΔH' was significant for periods (p < 0.05). After 365 days, significant reduction in lightness was observed for all groups. For CA, CA2, CAC, and MTA groups, the WID values decreased over time (p < 0.05). Conclusions The tested cements changed the color behavior of the samples, resulting in greater teeth darkening over time. Clinical significance There is no long‐term study assessing the discoloration induced by the different phases of CAC.

This study assessed the fracture resistance of simulated immature teeth reinforced with calcium aluminate cement (CAC) or mineral trioxide aggregate (MTA) containing calcium carbonate nanoparticles (nano-CaCO3). The microstructural arrangement of the cements and their chemical constitution were also evaluated. Forty-eight canines simulating immature teeth were distributed into 6 groups (n=8): Negative control - no apical plug or root canal filling; CAC - apical plug with CAC; CAC/nano-CaCO3 - apical plug with CAC+5% nano-CaCO3; MTA - apical plug with MTA; MTA/nano-CaCO3 - apical plug with MTA+5% nano-CaCO3; and Positive control - root canal filling with MTA. The fracture resistance was evaluated in a universal testing machine. Samples of the cements were analyzed under Scanning Electron Microscope (SEM) to determine their microstructural arrangement. Chemical analysis of the cements was performed by Energy Dispersive X-ray Spectroscopy (EDS). The fracture resistance of CAC/nano-CaCO3 was significantly higher than the negative control (p<0.05). There was no significant difference among the other groups (p>0.05). Both cements had a more regular microstructure with the addition of nano-CaCO3. MTA samples had more calcium available in soluble forms than CAC. The addition of nano-CaCO3 to CAC increased the fracture resistance of teeth in comparison with the non-reinforced teeth. The microstructure of both cements containing nano-CaCO3 was similar, with a more homogeneous distribution of lamellar- and prismatic-shaped crystals. MTA had more calcium available in soluble forms than CAC.