[Analysis of infinity optical thickness between nine kinds of composite resins with the same color mark].
OBJECTIVE
This study compared the infinity optical thickness of composite resins with the same color marks.


METHODS
In this test nine composite resins (shade A2) were used. A plastic mold (10mm in diameter, 4mm in height) was used to prepare 27 disk specimens. Color was measured by CIE L*a*b* relative to CIE source against a white and a black background, using a colorimeter. Color difference (DeltaE*) was calculated as DeltaE=[(DeltaL*(2)+(Deltaa*)(2)+(Deltab*)(2)](1/2). The heights of composite resins were recorded as DeltaE is approximately 1.5. The infinity optical thickness of composite resins when DeltaE = 1.5 was calculated by regression formulation.


RESULTS
The results indicated that composite resins with hybrid filler and opaque pigments were superior infinity optical thickness. Composite resins contain micro-filler were inferior infinity optical thickness.


CONCLUSIONS
Although composite resins with the same color mark had the similar fillers, they had different color and infinity optical thickness.
Department of Prosthet, Stomatological Hospital, Fourth Military Medical University, Xi'an 710032, China. xia889325@163.net
Chun-ming
CM
Xia
Chang-xi
CX
Shi
Ji-hua
JH
Chen
Yun
Y
Lan
Jie
J
Yu
Xu
X
Han
Wei
W
Wang