Department of Conservative Dentistry, College of dentistry, Chosun University, Korea.
Copyright © 2003 Korean Academy of Conservative Dentistry
In all groups except A1 shade of group III, the ΔE* values presented below 2.0, and group III showed the highest ΔE* values followed by group II and group I in a decreasing order(p<0.05).
In all shades and groups, the more the exposure time of xenon lamp and the lighter the shade were, the higher the tendency for discoloration (p<0.05).
The composite resins which was exposed to xenon lamp in the distilled water was more discolored than those in the air (p<0.05).
The major changes of composite resins which were exposed to xenon lamp in the air were an increase in yellowness through a positive shift of the b* value, and those in the distilled water were an increase in darkness and yellowness through a negative shift of the L* value and a positive shift of the b* value.
Group classification.
Result of color changes of group I, II and III after exposure of xenon lamp for 1 day.
ΔL*,Δa*,Δb*: color difference, ΔE*: total color difference.
Standard deviations are in parentheses.
Result of color changes of group I, II and III after exposure of xenon lamp for 7 days.
ΔL*,Δa*,Δb*: color difference, ΔE*: total color difference.
Standard deviations are in parentheses.
Statistical analysis of ΔE* of groupI between each shades by Tukey's HSD test (exposure to xenon lamp for 1 day).
*: significant differences (p<0.05)
Statistical analysis of ΔE* of groupI between each shades by Turkey's HSD test (exposure to xenon lamp for 7 days).
*: significant differences (p<0.05)
ΔL*,Δa*,Δb*: color difference, ΔE*: total color difference.
Standard deviations are in parentheses.
ΔL*,Δa*,Δb*: color difference, ΔE*: total color difference.
Standard deviations are in parentheses.
*: significant differences (p<0.05)
*: significant differences (p<0.05)