Effects of tooth bleaching protocols assisted by Er,Cr:YSGG and diode (980 nm) lasers on color change of resin‐based restoratives

Objective To evaluate color change of three resin‐based restorative materials after two laser‐assisted in‐office tooth bleaching protocols using Er,Cr:YSGG and diode (980 nm) lasers. Materials and Methods A nanohybrid composite resin (EP), a Bis‐GMA free composite resin (EPBio) and a resin‐matrix CAD‐CAM ceramic (HC) were tested. Ninety specimens were prepared and stored in artificial saliva. Group 1 received an in‐office bleaching treatment using 40% H2O2. The same bleaching procedure was assisted by Er,Cr:YSGG laser in Group 2 and by a diode laser (980 nm) in Group 3. Color measurements were performed using a double‐beam UV–Vis spectrophotometer at four time intervals (before, 24 h, 15 and 30 days), converted to L*, a*, and b* units of the CIELAB color space and assessed on the basis of 50:50% acceptability (ΔΕab* = 2.7 and ΔΕ00 = 1.77) and 50:50% perceptibility (ΔΕab* = 1.2 and ΔΕ00 = 0.81) thresholds. Three‐way ANOVA with repeated measurements was used for statistical analysis of the data. Results Color and whiteness changes did not exceed the established 50:50% acceptability thresholds. EP presented the highest color change after the bleaching followed by EPBio and HC (p ≤ 0.05). Three‐way ANOVA revealed that type of material and time interval significantly affected color change (p ≤ 0.001). Conclusions The tested bleaching treatments assisted by Er,Cr:YSGG and diode (980 nm) lasers did not induce unacceptable color and whiteness changes in the resin‐based restorative materials. Clinical Significance The tested Er,Cr:YSGG and diode (980 nm) laser‐assisted tooth bleaching protocols which may be recommended to accelerate the clinical procedures cannot affect the color of the existing resin‐based restorations in case they are accidentally exposed on the bleaching gel and laser irradiation.