Composites polymerized with halogen unit showed lower staining than all LED modes. Conclusion: This study suggest that light-curing mode influences the staining susceptibility of the tested composite. However specimens in GI revealed the least staining after 56-days of coffee immersion, and this result was statistically different from LED groups. Regarding 56- days of evaluation, specimens of GIV showed statistically significant colour change in red wine compared to other groups. Results: Regarding 7-day evaluation, colour change values of specimens immersed in coffee revealed no remarkable difference among curing modes (p>0.05) whereas specimens in GIV were significantly less stained compared to specimens in GII and GIII when immersed in red wine. Colour differences (∆E) between groups were submitted to statistical analysis.
Measurements were performed using spectrophotometer according to CIEL*a*b system at baseline and on 7, 28 and 56 days. Half of the specimens of each group (n=7) were stored in one of the staining media (red wine or coffee) for 10 min/day during experimental period. Methods: Disc-shaped specimens were prepared from nano-hybrid resin composite (Filtek Z550) and light- cured according to following modes: Halojen (GI), LED standard (GII), LED pulse (GIII) or LED ramp (GIV). This in vitro study investigated staining susceptibility of a nano-hybrid resin composite light-cured in different modes and immersed in different staining media. Both LEDs and halogen units are used for polymerization and different curing modes are improved to overcome inadequate polymerization. Aim: Sufficient polymerization remains as crucial for composites to prevent discoloration.
0 kommentar(er)
