RELIABILITY OF TWO STAIN REMOVAL REGIMES ON COLOR CHANGE OF CONTEMPORARY RESIN-BASED RESTORATIVE MATERIALS IN VITRO STUDY

Authors

1 Demonstrator of Conservative Dentistry Department, Faculty of Dentistry, Tanta University

2 Professor of Conservative Dentistry Department, Faculty of Dentistry, Tanta University

Abstract

Objective: To evaluate the reliability of two methods of stain removal on the color change of a nanohybrid composite resin (N-Fill) and a resin-modified glass ionomer (Ionolux) after being subjected to a combined effect of staining by commonly consumed beverages.
Materials and methods: Twenty disk-shaped specimens were prepared from each of the two tested materials (N-Fill) and (Ionolux) representing groups (I) and (II) respectively. All specimens were stained individually in tea and cola solutions for 30 days. The stained specimens were divided randomly according to the method used for stain removal into equal groups of ten specimens each (IA), (IIA), (IB) and (IIB). Specimens in group (IA) and (IIA) were polished with Sof-Lex system, while those in group (IB) and (IIB) were bleached with Opalescence Boost 40% HP. VITA Easy-shade spectrophotometer was used to measure the color of the specimens utilizing Commission international de l’éclairage L*a*b* color system. Measurements were performed four times: at baseline (original color), after staining, after polishing in group (IA) and (IIA) and after bleaching in group (IB) and (IIB). The color difference values (ΔE*) were calculated and statistically analyzed using One-way ANOVA and student t-tests at level of significance (P ≤ 0.05).
Results: Staining resulted in a perceptible ΔE* values (>3.3) in both materials. The recorded value (7.59) for Ionolux was beyond the clinically acceptable range (2.72-6.8) and was statistically significant different from that recorded for N-Fill (4.37). Polishing significantly affected color of N-Fill (ΔE*=19.05) compared to Ionolux (ΔE*=10.07). While ΔE* values recorded after bleaching (19.64 and 15.7) were not statistically significant from each other.
Conclusions: The tested polishing and bleaching procedures utilized to remove stain from both tested materials resulted in a significant color change that was beyond the clinically accepted range.

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