Analysis of the color alteration and radiopacity promoted by bismuth oxide in calcium silicate cement

Author(s)

Marina Angelica Marciano ^[1] ; Carlos Estrela ^[2] ; Rafael Francisco Lia Mondelli ^[1] ; Ronald Ordinola-Zapata ^[1] ; Marco Antonio Hungaro Duarte ^[1]

Affiliation

^[1] Univ Sao Paulo, Bauru Sch Dent, Dept Operat Dent Endodont & Dent Mat, Bauru, SP - Brazil

^[2] Univ Goias UFG, Sch Dent, Dept Prevent & Oral Rehabil, Goiania, Go - Brazil

• Document type: Journal article
• Source: Brazilian Oral Research; v. 27, n. 4, p. 318-323, 2013-07-00.

Abstract

The aim of the study was to determine if the increase in radiopacity provided by bismuth oxide is related to the color alteration of calcium silicate-based cement. Calcium silicate cement (CSC) was mixed with 0%, 15%, 20%, 30% and 50% of bismuth oxide (BO), determined by weight. Mineral trioxide aggregate (MTA) was the control group. The radiopacity test was performed according to ISO 6876/2001. The color was evaluated using the CIE system. The assessments were performed after 24 hours, 7 and 30 days of setting time, using a spectrophotometer to obtain the ΔE, Δa, Δb and ΔL values. The statistical analyses were performed using the Kruskal-Wallis/Dunn and ANOVA/Tukey tests (p < 0.05). The cements in which bismuth oxide was added showed radiopacity corresponding to the ISO recommendations ( > 3 mm equivalent of Al). The MTA group was statistically similar to the CSC / 30% BO group (p > 0.05). In regard to color, the increase of bismuth oxide resulted in a decrease in the ΔE value of the calcium silicate cement. The CSC group presented statistically higher ΔE values than the CSC / 50% BO group (p < 0.05). The comparison between 24 hours and 7 days showed higher ΔE for the MTA group, with statistical differences for the CSC / 15% BO and CSC / 50% BO groups (p < 0.05). After 30 days, CSC showed statistically higher ΔE values than CSC / 30% BO and CSC / 50% BO (p < 0.05). In conclusion, the increase in radiopacity provided by bismuth oxide has no relation to the color alteration of calcium silicate-based cements. (AU)

• FAPESP's process: 11/13573-3 - Physicochemical and biological properties of experimental Portland-based sealer containing different radiopacifying agents
• Grantee: Marina Angélica Marciano da Silva
• Support Opportunities: Scholarships in Brazil - Doctorate