Yazici A Rüya, Müftü Ali, Kugel Gerard
Department of Conservative Dentistry, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
J Contemp Dent Pract. 2007 Nov 1;8(7):21-8.
This study investigated the temperature rise caused by different light curing units and the temperature increase in dentin of different thicknesses.
Dentin discs of 1.0 and 2.0 mm thicknesses were prepared from extracted human mandibular molars. Temperatures were recorded directly at the surface of the light guide tip, under dentin discs with different thicknesses, and through a sandwich composed of 2 mm thick cured composite and dentin using a K-type thermocouple. The curing units used were two quartz-tungsten-halogen lights (Spectrum and Elipar Trilight-ET) and a light-emitting diode (LED).
The highest temperature rise was observed under a Mylar strip using ET standard mode. Under 1 and 2 mm thick dentin barriers, the lowest temperature rise was measured for the LED curing light. Significant differences in temperature rise existed among all curing units except between the Spectrum and ET exponential modes under a 1 mm thick dentin barrier with cured composite. Temperature rises were insignificant between the Spectrum and ET exponential modes and between two modes of Trilight when the same experimental setup was used under a 2 mm thick dentin barrier.
For all curing units, temperature elevation through 2 mm of dentin was less than for 1 mm of dentin thickness. The ET standard mode produced the highest and the LED produced the lowest temperature rise for all tested conditions. The thickness of dentin and light-curing unit might affect temperature transmission.
本研究调查了不同光固化机引起的温度升高以及不同厚度牙本质中的温度上升情况。
从拔除的人类下颌磨牙制备出厚度为1.0毫米和2.0毫米的牙本质圆盘。使用K型热电偶直接在光导尖端表面、不同厚度牙本质圆盘下方以及通过由2毫米厚的固化复合树脂和牙本质组成的三明治结构记录温度。所使用的固化机为两台石英钨卤素灯（Spectrum和Elipar Trilight - ET）和一台发光二极管（LED）灯。
在使用ET标准模式的聚酯薄膜条下观察到最高温度上升。在1毫米和2毫米厚的牙本质屏障下，LED固化灯的温度上升最低。除了在带有固化复合树脂的1毫米厚牙本质屏障下Spectrum和ET指数模式之间外，所有固化机之间的温度上升存在显著差异。当在2毫米厚牙本质屏障下使用相同实验设置时，Spectrum和ET指数模式之间以及Trilight的两种模式之间的温度上升不显著。
对于所有固化机，通过2毫米牙本质的温度升高低于1毫米牙本质厚度时的温度升高。在所有测试条件下，ET标准模式产生的温度上升最高，LED产生的温度上升最低。牙本质厚度和光固化机可能会影响温度传递。
