Effect of Two Bleaching Techniques on Teeth Discolored with Different Calcium Silicate-based Cements

Somayeh Hekmatfar, Vahid Samadi, Avissasadat Meraji, Karim Jafari — Mon, 11 May 2026 09:24:40 +0000

Objectives: The objective of this study was to investigate tooth discoloration caused by different calcium silicate-based cements (CSCs), and assess the efficacy of two bleaching techniques in restoring the original tooth color.

Materials and Methods: In this in vitro study, 54 sound teeth were divided into three groups (n=18) of Endocem, MTA Angelus, and calcium-enriched mixture (CEM) cement. Baseline color assessments were conducted using a spectrophotometer, with subsequent color evaluation after 3 months. Each group was divided into two subgroups of internal bleaching and internal/external bleaching. The bleaching procedure was performed over a 2-week period. Two-way ANOVA was applied to investigate the interaction effect of bleaching technique and time on color change (∆E). The Tukey’s test was used as post-hoc for pairwise comparisons. P≤0.05 was considered significant.

Results: The results indicated noticeable color change in all test groups, surpassing the perceptibility threshold (ΔE>3.3). Endocem exhibited the maximum discoloration, while CEM cement displayed the minimum. Significant differences were observed between Endocem and other groups (P<0.05). Regarding the L*, a*, and b* parameters, no significant differences were found between the two subgroups except in Endocem group, where internal/external bleaching caused a significantly greater increase in color parameters compared to internal bleaching (P=0.001).

Conclusion: Endocem induced more discoloration than MTA Angelus and CEM cement. However, there was no difference in efficacy between the internal and internal/external bleaching techniques (except in Endocem), both proving effective in restoring the original color of discolored teeth.

Frontiers in Dentistry

Effect of Two Bleaching Techniques on Teeth Discolored with Different Calcium Silicate-based Cements