目的:这项研究调查了三种光固化单元(LCU)的不同发射模式方案的影响:(i)激光(Monet);(ii)四波(PinkWave);(iii)常规LED(EliparS10)在光固化快速或常规填充树脂基复合材料(RBC)时对温度升高(ΔT)和转换度(DC)的影响。目的是将ΔT和DC相关联,和辐射暴露给红细胞标本。
方法:用两种批量填充RBC填充4mm深度的3D打印树脂模具:TetricPowerFill®(快速光聚合复合材料)(TPF)或TetricEvoCeram®批量填充(EVO)。使用了三个LCU:(i)Monet激光1s和3s(MONET-1s,MONET-3s);(ii)PinkWave四波在升压模式(PW-3s)中用于3s,在标准模式(PW-20s)中用于20s;(iii)EliparS10用于5s(S10-5s),在标准模式(S10-20s)中用于20s。之前获得了二维温度图,在使用热成像摄像机关闭LCU期间和之后的60s内。在五个深度分析热变化:(距RBC顶面0、1、2、3和4mm)。测定最大温升(Tmax)和平均温升(ΔT)。使用不锈钢分体式模具(4X4mm)从每种材料制备圆柱形样品,并用相同的方案进行光固化。使用傅里叶变换红外光谱(FTIR)在LCU关闭后1小时和120秒内测量DC。数据采用三因素方差分析,单向方差分析,独立t检验,和Tukey事后检验(p<0.05)。
结果:通过各种辐照方案提供的辐射暴露在4.5-30.3J/cm2之间。MONET-1s和PW-3s的短曝光时间可提供最低的辐射曝光量(分别为4.5和5.2J/cm2),并产生最低的ΔT和DC。PW-20s标准模式下的曝光时间越长,S10-20s,MONET-3产生了最高的Tmax,ΔT,和DC两种复合材料。不同深度的复合材料之间的ΔT范围显着变化(31.7-49.9°C)。TPF的DC介于30-65%之间,EVO介于15.3-56%之间。TPF有更高的Tmax,与EVO相比,所有深度和DC的ΔT,在LCU协议中(p<0.05),除PW-20s和MONET-3s外。修复体的冠状部分(1-2mm)具有最高的ΔT。在120s后,4毫米深度的ΔT和DC之间存在正相关。意义:更长,或标准,与较短或高辐照度方案相比,LCU的暴露时间提供了更大的辐射暴露,并且具有更高的DC和ΔT。当快速光聚合的RBC在短时间(1-5s)内接受高辐照度时,与传统的填充RBC相比,其具有相对优异的热和转化结果。
OBJECTIVE: This study investigated effects of the different emittance-mode protocols from three light curing units (LCUs): (i) a Laser (Monet); (ii) a quad-wave (PinkWave); (iii) a conventional LED (Elipar S10) on the temperature rise (ΔT) and degree of conversion (DC) when photo-curing fast or conventional bulk-fill resin-based composites (RBC). The aim was to correlate ΔT and DC, and the radiant exposure delivered to RBC specimens.
METHODS: A 3D-printed resin mold of 4 mm depth was filled with two bulk-fill RBCs: Tetric PowerFill® (fast photo-polymerised composite) (TPF) or Tetric EvoCeram® Bulk-Fill (EVO). Three LCUs were used: (i) Monet laser for 1 s and 3 s (MONET-1 s, MONET-3 s); (ii) PinkWave quad-wave used for 3 s in Boost mode (PW-3 s) and for 20 s in standard mode (PW-20 s); (iii) Elipar S10 for 5 s (S10-5 s) and for 20 s in standard mode (S10-20 s). 2-dimensional temperature maps were obtained before, during and for 60 s after the LCU had turned off using a thermal imaging camera. Thermal changes were analysed at five depths: (0, 1, 2, 3, and 4 mm from the top surface of the RBC). The maximum temperature rise (Tmax) and the mean temperature rise (ΔT) were determined. Cylindrical-shaped specimens were prepared from each material using a stainless-steel split mold (4 × 4 mm) and light-cured with the same protocols. The DC was measured for 120 s and at 1 h after LCU had turned off using Fourier Transform Infrared Spectroscopy (FTIR). Data were analysed using Three-way ANOVA, One-way ANOVA, independent t-tests, and Tukey post-hoc tests (p < 0.05).
RESULTS: Radiant exposures delivered by the various irradiation protocols were between 4.5-30.3 J/cm2. Short exposure times from MONET-1 s and PW-3 s delivered the lowest radiant exposures (4.5 and 5.2 J/cm2, respectively) and produced the lowest ΔT and DC. The longer exposure times in the standard modes of PW-20 s, S10-20 s, and MONET-3 s produced the highest Tmax, ΔT, and DC for both composites. The ΔT range among composites at different depths varied significantly (31.7-49.9 °C). DC of TPF ranged between 30-65% and in EVO between 15.3-56%. TPF had higher Tmax, ΔT for all depths and DC compared to EVO, across the LCU protocols (p < 0.05), except for PW-20 s and MONET-3 s. The coronal part of the restorations (1-2 mm) had the highest ΔT. There was a positive correlation between ΔT and DC at 4-mm depth after 120 s SIGNIFICANCE: Longer, or standard, exposure times of the LCUs delivered greater radiant exposures and had higher DC and ΔT compared to shorter or high-irradiance protocols. The fast photo-polymerised RBC had comparatively superior thermal and conversion outcomes when it received a high irradiance for a short time (1-5 s) compared to the conventional Bulk-Fill RBC.