2014 Volume 57 Issue 2 Pages 162-169
Purpose: Recently, bulk-fill resin composites, which enable increments up to 4 mm thick to be cured in one step, have been developed. This study was conducted to evaluate the mechanical properties of bulk-fill resin composites.
Methods: Five resin composites were used in this study (Bulk-fill: Tetric N-Ceram Bulk Fill (Ivoclar Vivadent) and SDR (Dentsply DeTrey); Universal: Tetric N-Ceram (Ivoclar Vivadent) and Esthet・X HD (Dentsply DeTrey); Flowable: Tetric N-Flow (Ivoclar Vivadent) ). Depth of cure, inorganic filler content, flexural properties and polymerization shrinkage were measured. SEM observation of the cured resin composites was also conducted.
Results: The depth of cure of the bulk-fill resin composites ranged from 3.42 to 4.27 mm, which is significantly greater than that of conventional resin composites. The inorganic filler contents of the employed resin composites ranged from 60.3 to 77.5 wt% and those of the universal resin composites were significantly higher than those of the flowable resin composites. The flexural strength and elastic modulus of bulk-fill resin composites ranged from 123.3 to 127.5 MPa and from 7.0 to 8.0 GPa, respectively. The polymerization shrinkage of bulk-fill resin composites after 180 sec of irradiation ranged from 2.12 to 2.23 vol%; these values are the same or lower than those of conventional resin composites.
Conclusions: Based on the results of this study, the depth of cure of bulk-fill resin composites was higher than that of conventional resin composites. In addition, the mechanical properties of bulk-fill resin composites were similar to or better than those of conventional resin composites. Therefore, bulk-fill resin composites have good potential for the development of resin composites.
