The Effect of Shade and Curing Time on Depth of Cure (DOC) in Two Types of Composites, Polymerized with a Halogen Light Cure System
 
Sa di Shirshab Thiab, Qasim AbduI-Kareem Mohammad, Ahmed Ghanim Mahdi
Kufa med J  Vol 13 (1) 2010     165-184
The aim of study was to determine the depth of cure DOC of different shades in light-activated composite polymerized with a halogen light cure unit with different curing times. 90 samples were prepared that divided into 18 groups of 5 samples for each group using a tube-like stainless steel mold utilizing two composite materials (SwissTEC and Composan LCM), three shades (Al, A2 and A3) cured for 20, 40 and 60 seconds. The cured samples removed from the mold and uncured material scrapped manually and remaining length of each sample measured by micrometer. 3-way ANOVA (at p ? 0.05) followed by Duncan multiple range test showed that DOC of SwissTEC is significantly higher than Composan LCM, lighter shade Al give more DOC than others followed by A2 and A3 successively, and 60s curing time resulted in better DOC than 40s and the latter was better than 20s.The conclusions of this study are that all materials, shades and cuing times passed the ISO 2000/4049 requirements, Darker shades had less DOC than lighter shades, but increasing the curing time can improve DOC of darker shades. The method used in this study may be used as one of the simple methods for checking the efficiency of halogen LCUs in dental clinics.