Journal of Dental Science and Medicine
Open Access

Abstract

Background: In an attempt to fasten and simplify the restoration process, a new class of composite resins, called the bulk fill composite resins have been introduced, which has been claimed to achieve a depth of cure (DOC) of 4 mm without affecting the properties of the material. Purpose: The Purpose of this study was to investigate the effect of different shades, thicknesses and viscosities on the DOC of bulk-fill composites. Materials and method: Four bulk-fill composites [FiltekTM Bulkfill Flowable(FBF),FiltekTM Bulkfill posterior (FBP)،Tetric N-Flow bulkfill(TNF), Tetric N-Ceram bulkfill(TNC)] and a conventional composite, FiltekTM Z250XT Universal(FZ) were evaluated. samples (n=5) were made using two different shades( light and dark ) ,thicknesses (2 and 4 mm ) and viscosities( flowable and sculptable ). Microhardness was conducted on top and bottom surface using Vickers microhardness tester and DOC calculated as the bottom/top ratio. Statistical analysis was done using a mannwhitney test at p<0.05. Results: DOC ranged between 52-95%. FBF composite exhibited the lowest overall hardness numbers. At 2-mm thickness, all the samples achieved an appropriate DOC. However, at 4-mm thickness, only the light shades for FBF and TNF samples achieved a DOC very close to 0.8. At 4-mm thickness, the light shades for FBF, TNF and FZ samples exhibited significantly higher DOC compared to dark shades. For 4-mm-thick samples, DOC of FB )dark and light shades (and DOC of TN (light shade( were different in the flowable type from the sculptable type. Conclusion: Shade and viscosity influence DOC of bulk-fill composites at 4-mm depths. For bulk-fill composites, 20s light curing appears insufficient for 4mm bulk-fill placement

Biography

Maryam Novin Rooz is a dentists and Department of operative dentistry, School of dentistry, Zanjan University of medical sciences, Zanjan, Iran.