But, there were no significant differences in color change among groups. The polymerization process www.selleckchem.com/products/Bosutinib.html in Indirect Inlay System (Tescera ATL, Bisco, USA) combines two curing mechanisms: light and heat under water. After complete development of the restoration, the final cure is accomplished in a heat cup with the restoration submerged in water.38,39 In the current study, CIE b* value (yellow-blue) decreased after polymerization. The composite resins that polymerized with inlay oven showed the highest ��*b values which means less yellow color in specimens. The CIE *b values of the polymerization inlay oven is significantly different from the other four groups. The highest ��C*ab values were observed in specimens polymerized in an inlay oven.
In this inlay system, the final cure is accomplished in a heat cup with the restoration submerged in water. Therefore, the highest ��*b and ��C*ab values may be observed in this polymerization system. Further in vitro study on this subject should be performed. Polymerized composite resins tend to have greater diffuse reflectance than unpolymerized composite resins. This alteration reflects the increase of refractive index of the resin phase associated with monomer conversion (into polymer) of monomer mixtures, while refractive index of the filler remains unchanged.3 Lee and Powers40 reported that lightness (CIE L*) increased or decreased depending on the material and shade after polymerization. In their study, Kim and Lee4 reported that CIE L* values decreased after polymerization except one composite resin.
A study by Marais et al41 has suggested that power density (irradiance) does not have an effect on conversion of composite resin at depths beyond 2 mm; because of this, in the current study, specimen thickness was 2 mm. The specimens were cured from both sides, effectively reducing thickness of resin being cured to 1 mm to get maximum conversion. Tak et al22 used 2mm-thick specimens. In the previous study, the specimen thickness was 1mm.4 The difference in thickness may influence the amount of Anacetrapib color change after polymerization. CONCLUSIONS Within the limitations of this in vitro study, the following conclusions were drawn: – The color changes of composite resin material in all groups were above the clinically acceptable value (��E*ab 3.3). There were no significant differences in total color change among the groups. – All specimens became darker during investigation (��L*< 0). – The composite resins that polymerized with inlay oven showed the highest ��*b values which means less yellow color in specimens.