Comparative Spectrophotometric Assessment of Crown Discoloration from Diverse Endodontic Sealers

BACKGROUND Crown discoloration is a significant aesthetic concern in endodontics, particularly following the use of obturation sealers. Using spectrophotometric analysis, this study evaluated the extent of discoloration caused by 4 types of sealers: mineral trioxide aggregate (MTA)-based, zinc oxide eugenol (ZnOE)-based, calcium hydroxide (Ca(OH)2)-based, and resin-based sealers. MATERIAL AND METHODS We randomly divided 75 extracted maxillary central incisors into 5 groups: 4 experimental groups and 1 control group. Standardized endodontic treatment was performed, with the respective sealers placed according to the manufacturer's instructions. Coronal discoloration was measured using a spectrophotometer at baseline, immediately after treatment, and at 1 and 6 months. Chromatic parameters (CIE L*, a*, b*) and total color difference (ΔE) were analyzed. Statistical analysis included repeated-measures ANOVA and post hoc tests. RESULTS All sealers caused significant crown discoloration over time. The MTA-based sealer exhibited the least discoloration, while ZnOE-based sealers had the highest ΔE values. Significant changes were noted in chromatic parameters across materials and time. ΔL (lightness change) ranged from 1.53±1.67 for MTA to 4.06±1.96 for Resin-based sealers at baseline to immediately after treatment. Resin-based sealers had the highest mean change (2.18±2.40) in Δb. For ΔE, significant differences were found between materials, with Ca(OH)₂ showing the highest mean change (5.04±2.59). CONCLUSIONS Endodontic sealers can induce varying degrees of crown discoloration, with ZnOE-based sealer causing the most significant changes. Clinicians should consider the aesthetic impact of sealer selection, particularly for anterior teeth.