Comparative Spectrophotometric Evaluation of Coronal Discoloration by Calcium Hydroxide and Propolis

Abstract Background Tooth discoloration affects esthetics; intracanal medicaments like calcium hydroxide and propolis may cause color changes, requiring evaluation of their discoloration potential using spectrophotometry. Aims and Objectives The aim of the present study was to evaluate the discoloration potential of different intracanal medicaments. The objectives were to assess discoloration caused by calcium hydroxide [Ca (OH)₂] and propolis at 1 week and 21 days using a spectrophotometer, and to comparatively evaluate their discoloration potential. Materials and Methods A total of 46 extracted human permanent mandibular premolars were prepared up to size #40 using the step-back technique. Samples were randomly divided into two groups (n = 23): Ca (OH)₂ and 30% propolis. Intracanal medicaments were placed up to working length and sealed with IRM to the CEJ. Samples were incubated at 37°C with 100% humidity for 3 weeks. Color was assessed at baseline, 1 week, and 21 days (T0, T1, T2) using a spectrophotometer based on the CIE Lab* system. ΔE values were calculated and analyzed using ANOVA, Tukey's/Dunn's post hoc tests, and paired t-tests (p < 0.05). Results At 1 week, no statistically significant differences were observed between the calcium hydroxide and propolis groups for L*, a*, b*, or ΔE values (p > 0.05), indicating comparable color stability. However, at 21 days, while L* and a* values remained statisti -cally similar (p > 0.05), the calcium hydroxide group demonstrated significantly higher b* values (p = 0.0065) and ΔE values (p = 0.0032) compared to the propolis group, indicating greater yellow discoloration and overall color change. Conclusion Both medicaments caused time-dependent discoloration; however, propolis showed better color stability than calcium hydroxide, making it more suitable for esthetic cases.