title: Coronal Discoloration Induced by Calcium-Enriched Mixture, Mineral Trioxide Aggregate and Calcium Hydroxide: A Spectrophotometric Analysis.
abstract: BACKGROUND
  The aim of this study was to compare the discoloration potential of calcium-enriched mixture (CEM) cement, white mineral trioxide aggregate (WMTA) and calcium hydroxide (CH), after placement in pulp chamber.
  
  
  METHODS
  Access cavities were prepared in 40 intact maxillary central incisors. Then, a 2×2 mm box was prepared on the middle third of the inner surface on the buccal wall of the access cavity. The specimens were randomly assigned into four groups; the boxes in the control group were left empty, in groups 1 to 3, the boxes were filled with CH, WMTA and CEM cement, respectively. The access cavities and the apical openings were sealed using resin modified glass ionomer (RMGI). The color measurement was performed with a spectrophotometer at the following intervals: before (T0), immediately after placement of the filling material (T1), one week (T2), 1 month (T3), 3 months (T4) and 5 months (T5) after filling of the box and finally immediately after removing the material from the boxes (T6). Color change (Δ E) values were calculated using the sample Kolmogorov-Smirnov test to determine the normal distribution of data, followed by ANOVA, repeated measured ANOVA and post-hoc Tukey's tests.
  
  
  RESULTS
  All materials led to clinically perceptible crown discoloration after 1 week. The highest ΔE value belonged to WMTA group. Discoloration induced by CEM cement was not significantly different from CH or the control group (P>0.05).
  
  
  CONCLUSIONS
  CEM cement may be the material of choice in the esthetic region, specifically pertaining to its lower color changing potential compared to WMTA.
authors: Dental Materials Research Center, Department of Operative Dentistry, Dental School, Babol University of Medical Sciences, Babol, Iran;
authors: Behnaz
authors: B
authors: Esmaeili
authors: Dental Materials Research Center, Department of Operative Dentistry, Dental School, Babol University of Medical Sciences, Babol, Iran;
authors: Homayoun
authors: H
authors: Alaghehmand
authors: Department of Operative dentistry, Dental School, Golestan University of Medical Sciences, Golestan, Iran;
authors: Tavoos
authors: T
authors: Kordafshari
authors: Dental Materials Research Center, Department of Operative Dentistry, Dental School, Babol University of Medical Sciences, Babol, Iran;
authors: Ghazaleh
authors: G
authors: Daryakenari
authors: Department of Endodontics, Dental School, Babol University of Medical Sciences, Babol, Iran;
authors: Maryam
authors: M
authors: Ehsani
authors: Health Research Center, Babol University of Medical Sciences, Babol, Iran.
authors: Ali
authors: A
authors: Bijani
keywords: Calcium-Enriched Mixture Cement; Mineral Trioxide Aggregate; Spectrophotometry; Tooth Discoloration