@Article{, title={The Effect of Different Light Cure Systems on Microhardness of Bulk Fill Composite Materials}, author={Linz A. Shalan and Samer Awn Thiab}, journal={Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد}, volume={29}, number={2}, pages={13-20}, year={2017}, abstract={Background: The aim of this study was to evaluate the effect of three types of light curing devices QTH, LED andFlashmax on the surface microhardness of three types of bulkfill composite resins; Filtek Bulkfill posterior composite( 3M), Tetric Evo Ceram ( Ivoclar Vivadent) and Sonicfill composite ( Kerr)Materials and methods: Total number of 90 samples was prepared, 30 samples for each type of bulkfill composite,were divided into three main groups, group A: Filtek posterior bulkfil (3M), group B: Tetric Evo Ceram (IvoclarVivadent) and group C: contain Sonicfill composite (kerr). Which then divided into three subgroups (n= 10) (1)Samples cured by QTH system (2) Samples cured by LED system and (3) samples cured by Flashmax system then allsamples were subjected for microhardness test (by Vickers hardness tester). The data were recorded and statisticallyanalyzed, by the ANOVA and the Tukey test.Results: the data was subjected to statistical analysis using one way ANOVA and Tukey test, the result revealed thatthere was a high significant difference among the tested units with LED had high VHN values followed by QTH whileFlashmax had lowest VHN values, also there was high significant difference among the tested materials in whichSonicfill composite had higher VHN value followed by Tetric EvoCeram while Filtek bulkfill posterior composite hadthe lowest VHN.Conclusions: microhardness of the composite resin materials depend upon energy of the curing device, time ofexposure, composition of the composite material

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