Objective
The objective of this study was to evaluate the effect of finishing protocol and exposure to staining solutions on color stability of dental resin composites.
Materials and Methods
A nanofill and microhybrid composite, three finishing protocols (mylar,
Soflex
disc, and white polishing stone) and four staining solutions (tea, red wine, khat extract—two concentrations, control—distilled water) were evaluated. A digital spectrophotometer was used for color change (Δ
E
) measurements employing the CIE‐Lab‐color system. Paired/independent‐sample
t
test and two‐way analysis of variance (ANOVA) followed by Tukey's honestly significant difference posthoc test were used for inferential statistics at
α
= .05.
Results
Soflex
finish was associated with least staining and comparable color stability for the two materials in tea and red wine. In Khat 2, microhybrid composite had statistically significant better color stability than nanofill for
Soflex
finish (14 days
t
= 3.270,
p
= .011). For microhybrid composite, mylar resulted in highest mean Δ
E
, whereas
Soflex
recorded the least in all staining solutions. For nanofill composite, white stone resulted in highest mean Δ
E
, whereas
Soflex
demonstrated the least mean Δ
E
in all staining solutions, except red wine where mylar demonstrated the least mean Δ
E
. For mylar finish, nanofill demonstrated statistically significant better color stability than microhybrid in both red wine (14 days
t
= 4.902,
p
= .001) and Khat 1 (14 days
t
= 3.252,
p
= .012). For stone finish, microhybrid demonstrated statistically significant better color stability than nanofill in all staining solutions (14 days
t
≥ 4.785,
p
≤ .001). Two‐way ANOVA showed a statistically significant difference in mean Δ
E
between and within specimens (
F
= 42.658,
p
< .001). All staining solutions caused clinically unacceptable discoloration for mylar and white stone finish. For
Soflex
finish, red wine produced clinically unacceptable color difference beyond 48 h.
Conclusion
There was a difference in color stability of resin composites depending on filler type, further influenced by finishing protocol.
Soflex
disc finish results in better color stability than mylar and white stone in both microhybrid and nanofill composites.
...