The Discoloration effect of White Mineral Trioxide Aggregate (WMTA), Calcium Enriched Mixture (CEM), and Portland Cement (PC) on Human Teeth

Background The aim of this study was to evaluate the discoloration induced by CEM cement, Portland cement (PC) and MTA mixed with propylene glycol (MTA-PG) in comparison to White MTA. Material and Methods Ninety extracted premolar and canine teeth were resected 2 mm below the CEJ. The coronal part of crown was prepared with peeso reamer and Gates-Glidden drills, and the specimens were randomly divided into 4 experimental (n=20) and one control (n=10) groups. The tooth crowns in experimental groups 1 to 4 were filled with White MTA, PC, CEM cement and MTA-PG, respectively; and in group 5, the teeth were kept empty. After incubation, digital photographs of teeth were acquired at 4 time points (before, immediately after placing the materials, 3 and 6 months afterwards). Images were transferred to Adobe Photoshop CS4 and CIE L*a*b color space was used for tooth shade assessment. One-Way ANOVA and One-Sample t-test were used to compare discoloration of teeth between groups. Results Significant statistical discoloration was only observed in the cervical one third of all groups at each time points (except between 3 and 6 months). Tooth discoloration was greatest in PC and lower in MTA and MTA-PG at the end of 6 months. The tooth discoloration between immediately and 3 months after placing the materials had significant difference only between MTA and PC; and also the tooth discoloration between immediately and 6 months after placing the materials was observed only between PC and MTA, and PC and MTA-PG. Conclusions All of the experimental biomaterials caused tooth discoloration after 6 months, of those, PC had the most and MTA and MTA-PG had the least discoloration effect. Key words:Mineral trioxide aggregate (MTA). Calcium enriched mixture (CEM). Propylene glycol. Portland cement.