. 2012 Sep-Oct;20(5):576–580. doi: 10.1590/S1678-77572012000500014

Table 3.

Hardness ratios (standard deviations) of composite resin specimens light cured with light curing units covered with layers of an infection control barrier

LCU	Control	1 Layer	2 Layers	4 Layers	8 Layers
FL2	89.8 (2.0)^Aa	88.2 (5.1)^Aba	84.5 (6.0)^Aba	83.4 (5.3)^Ba	76.4 (5.7)^Ca
O360	80.0 (5.2)^Ab	76.1 (4.4)^Abb	72.0 (5.2)^BCb	66.9 (4.7)^Cb	65.6 (6.2)^Cb

Values having the same capital letters in the rows and the same small letters in the columns are not statistically significant (p>0.05). LCU= light curing unit; FL2= Elipar FreeLight 2; O360= Optilux 360