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Updated: Mar 18, 2026

Evaluating the Effects of Different Polishing Methods on Color Stability of Dental Restorations in Pediatric Dentistry
Published on: June 6, 2025
Clinical Evaluation of Etched Enamel Discoloration following Immediate and Delayed Exposure to Colored Agents
Neda Eslami1, Mohammad Basafa2, Arezoo Jahanbin3
1Dental Research Center, Faculty of Dentistry, Mashhad University of Medical Sciences, Mashhad 9138813944, Iran.
Abstract:
Introduction. The aim was to evaluate etched enamel discoloration following immediate and delayed exposure to colored agents. Method & Material. 64 premolars were divided into four groups. Buccal surface of the teeth was divided into two halves and baseline color values were measured. One half was covered and the other half was etched and dried. In first and second groups, the patients did not eat any colored agents for the next 24 hours. Both halves were colorimetered after 48 hours and 1 month, respectively. In third and fourth groups, the process was similar, but the patients drank cola and avoid eating any other colored agents and the teeth were colorimetered after 48 hours and 1 month, respectively. Color change values (ΔE) of each half were calculated according to CIE lab system. Sign test was used to compare values of etched and unetched halves. P < 0.08 was set as significant. Results. A significant difference was observed in groups III and IV regarding comparison of ΔE of the etched and control enamel (P = 0.077). Conclusion. Exposure of etched enamel to colored agents in the first 24 hours after etching can affect its color which remains at least for one month.
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