Monte Alto Raphael Vieira, Guimarães José Guilherme Antunes, Poskus Laiza Tatiana, da Silva Eduardo Moreira
Department of Restorative Dentistry, School Of Dentistry, Federal Fluminense University, Ingá, Niterói, RJ.
J Appl Oral Sci. 2006 Apr;14(2):71-6. doi: 10.1590/s1678-77572006000200002.
This study evaluated the depth of cure of five dental composites submitted to different light-curing modes.
Canal-shaped cavities with 5mm of length were prepared on the buccal surfaces of extracted third molars, and restored using P-60, A-110, Admira, Z-250 and Supreme resin composites. Materials were light-cured from the top, according to three modes (Group 1- Conventional (C): 500 mW/cm(2) / 40 s; Group 2 - Soft-Start (SS): 250 mW/cm(2)/ 20 s + 500 mW/cm(2)/ 20 s + 500 mW/cm(2)/ 10 s and Group 3 - LED: 250 mW/cm(2)/ 40 s). After that, cavity longitudinal surfaces were polished and marked with a millimeter scale of 4mm of length. Depth of cure was evaluated by means of Knoop hardness number (KHN), so that five indentations were performed at each millimeter. Original data were submitted to three-way ANOVA and Fisher's LSD test (alpha = 0.01).
All materials presented a significant reduction on KHN from first to third millimeter. Regarding depth of cure, the results obtained for Conventional and Soft-Start modes were similar, but statistically superiors to those found for group 3 (LED).
This performance may be related to the differences among energy densities obtained with different light-curing modes.
本研究评估了五种牙科复合材料在不同光固化模式下的固化深度。
在拔除的第三磨牙颊面制备长度为5mm的根管状窝洞，并用P-60、A-110、Admira、Z-250和Supreme树脂复合材料进行修复。材料从顶部进行光固化，分为三种模式（第1组-传统模式（C）：500 mW/cm² / 40秒；第2组-软启动模式（SS）：250 mW/cm² / 20秒 + 500 mW/cm² / 20秒 + 500 mW/cm² / 10秒；第3组-LED模式：250 mW/cm² / 40秒）。之后，窝洞纵向表面进行抛光，并用4mm长的毫米刻度标记。通过努氏硬度值（KHN）评估固化深度，在每毫米处进行五次压痕。原始数据进行三因素方差分析和Fisher最小显著差异检验（α = 0.01）。
所有材料从第一毫米到第三毫米的KHN均显著降低。关于固化深度，传统模式和软启动模式获得的结果相似，但在统计学上优于第3组（LED模式）。
这种性能可能与不同光固化模式获得的能量密度差异有关。
