Effect of 2 Bleaching Agents with a Content of High Concentrated Hydrogen Peroxide on Stained 2 CAD/CAM Blocks and a Nanohybrid Composite Resin: An AFM Evaluation

Abstract

The aim of this study was to evaluate color stability of 3 restorative materials, discoloration ability of different solutions, efficacy of 2 office bleaching agents, and surface roughness and topography. Sixty specimens for Clearfil Majesty Esthetic (CME), Lava Ultimate (LU), and Vita Enamic (VE) were prepared. They were immersed into 3 staining solutions for 2 weeks and then they were bleached. According to the measured L⁎, a⁎, and b⁎ parameters described by CIELAB system, color changes (ΔE00), translucency parameters (TP), whiteness index values (W⁎), and changes in closeness to pure white (ΔW⁎) were calculated. Then 3 specimens from each group were scanned with an atomic force microscope for surface analysis. After staining, CME groups and control groups of LU and VE showed clinically acceptable color changes (ΔE00 < 1,8). After bleaching, while a reverse effect on color was observed, VE showed the furthest color values to pure white. There was no statistically significant difference between whiteness index values of LU and CME. LU was the most translucent material during the study and TP values of materials showed minimal differences. Most of the VE groups and a control group of LU showed surface roughness (Ra) values higher than critical value for biofilm accumulation (0,2 μm).

Changes in Optical Characteristics and Surface Topography of CAD/CAM Materials after Bleaching Applications: An AFM Evaluation

“…Thus, the second null hypothesis was accepted. However, in a previous study 19 which evaluated the effect of the same in-office bleaching agents on the surface roughness and topography of LU and VE, it has been reported that in-office bleaching agents caused alterations on the surface of these materials. However, as discussed above, subjecting the specimens to staining solutions before bleaching may have contributed to the differences observed with this study.…”

“…Sixty rectangular‐shaped specimens with the dimensions of 6 ± 0.3 × 7 ± 0.3 × 1.3 mm were prepared with the use of a low‐speed diamond saw (Micracut 201, Metkon®, Bursa, Turkey) for each material. The number of specimens was determined according to a statistical power analysis conducted by a software program (G*Power 3.1) with a statistical power of 80% and significance level of 0.05 (α) based on a previous study . The LU and VE specimens were first polished with a polishing disc system (Sof‐Lex XT discs, 3M ESPE, St. Paul, MN) with coarse, medium, fine, and superfine grain size, respectively.…”

“…The number of specimens was determined according to a statistical power analysis conducted by a software program (G*Power 3.1) with a statistical power of 80% and significance level of 0.05 (α) based on a previous study. 19 The LU and VE specimens were first polished with a polishing disc system (Sof-Lex XT discs, 3M ESPE, St. Paul, MN) with coarse, medium, fine, and superfine grain size, respectively. Then, for the LU specimens, final polishing was performed with a polishing set (The Meisinger Luster for Lava Ultimate, Hager&Meisinger GmbH, Dusseldorf, Germany) including diamond-coated rubber-polishing wheels (coarse/medium), a soft bristle brush and finally a muslin rag wheel with fine soft extraoral polishing paste (VH Technologies Ltd, Lynnwood, WA) according to the instructions of the manufacturer.…”

Effect of Home Bleaching on the Color Matching of Composite Resin Restorations

“…To determine the subjective errors in this study, the color determination and evaluation was performed using the spectrophotometer apparatus, which is currently the most accurate tool for discoloration measurement [18]. It is a more objective method than the eye method (in 93.3% of cases), with an accuracy rate higher than current techniques (33% higher) [19].…”

Evaluation of the Color Matching of Composite Resin Restoration used for Repair with Initial Composite Resin Restoration

“…According to various studies, the internal and external factors associated with the patients' habits and medical history as well as the exposure time and concentration of the staining material may impact the color stability of the tooth and the restorative materials [22]. Color change in the composite resin restorations may be physiological, chemical, hydrophilic or hydrophobic reactions and may be caused by water absorption due to different reasons, such as composition (optical primer, actuator, resin matrix, and fillers).…”