Algamaiah Hamad, Yang Jiawei, Alayed Abdulaziz, Alshabib Abdulrahman, Alshehri Abdullah, Watts David C
Department of Restorative Dental Science, College of Dentistry, King Saud University, P.O. Box 60169, Riyadh 11545, Saudi Arabia.
Department of prosthodontics, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China; National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Dent Mater. 2024 Mar;40(3):458-465. doi: 10.1016/j.dental.2023.12.006. Epub 2023 Dec 21.
To assess visually and quantitatively the contributions of the adhesive layer photopolymerization and the subsequent resin composite increment to spatio-temporal maps of temperature at five different cavity locations, subjected to two irradiance curing protocols: standard and ultra-high.
Caries-free molars were used to obtain 40, 2 mm thick dentin slices, randomly assigned to groups (n = 5). These slices were incorporated within 3D-printed model cavites, 4 mm deep, restored with Adhese® Universal bonding agent and 2 mm thick Tetric® Powerfill resin composite, and photocured sequentially, as follows: G1: control-empty cavity; G2: adhesive layer; G3 composite layer with no adhesive; and G4 composite layer with adhesive. The main four groups were subdivided based on two curing protocols, exposed either to standard 10 s (1.2 W/cm) or Ultra high 3 s (3 W/cm) irradiance modes using a Bluephase PowerCure LCU. Temperature maps were obtained, via a thermal imaging camera, and numerically analyzed at 5 locations. The data were analyzed using two-way ANOVA followed by multiple one-way ANOVA, independent t-tests and Tukey post-hoc tests (α = 0.05). T, ΔT, T (integrated area under the curve) and time-to-reach-maximum-temperature were evaluated.
Two-way ANOVA showed that there was no significant interaction between light-curing time and location on the measured parameters (p > 0.05), except for the time-to-reach-maximum-temperature (p < 0.05). Curing the adhesive layer alone with the 10 s protocol resulted in a significantly increased pulpal roof temperature compared to 3 s cure (p < 0.05). Independent T-tests between G3 and G4, between 3 s and 10 s, confirmed that the adhesive agent caused no significant increases (p > 0.05) on the measured parameters. The ultra-high light-curing protocol significantly increased ΔT in composite compared to 10 s curing (p < 0.05).
When the adhesive layer was photocured alone in a cavity, with a 2 mm thick dentin floor, the exothermal release of energy resulted in higher temperatures with a 10 s curing protocol, compared to a 3 s high irradiance. But when subsequently photocuring a 2 mm layer of composite, the resultant temperatures generated at pulpal roof location from the two curing protocols were similar and therefore there was no increased hazard to the dental pulp from the immediately prior adhesive photopolymerization, cured via the ultra-high irradiation protocol.
通过视觉和定量分析，评估在两种辐照固化方案（标准方案和超高方案）下，粘结层光聚合以及随后的树脂复合材料增量对五个不同窝洞位置的时空温度图的影响。
使用无龋磨牙获取40片2毫米厚的牙本质切片，随机分为几组（每组n = 5）。将这些切片嵌入3D打印的4毫米深的模型窝洞中，用Adhese®通用粘结剂和2毫米厚的Tetric® Powerfill树脂复合材料进行修复，并按以下顺序进行光固化：G1：对照组 - 空窝洞；G2：粘结层；G3：无粘结剂的复合层；G4：有粘结剂的复合层。主要的四组再根据两种固化方案进一步细分，使用Bluephase PowerCure LCU分别接受标准的10秒（1.2 W/cm）或超高的3秒（3 W/cm）辐照模式。通过热成像相机获取温度图，并在5个位置进行数值分析。数据采用双向方差分析，随后进行多个单向方差分析、独立t检验和Tukey事后检验（α = 0.05）。评估了温度（T）、温度变化量（ΔT）、曲线下积分面积（T）以及达到最高温度的时间。
双向方差分析表明，除了达到最高温度的时间（p < 0.05）外，光固化时间和位置对测量参数没有显著交互作用（p > 0.05）。与3秒固化相比，采用10秒方案单独固化粘结层会导致髓顶温度显著升高（p < 0.05）。G3和G4之间、3秒和10秒之间的独立t检验证实，粘结剂对测量参数没有显著增加（p > 0.05）。与10秒固化相比，超高光固化方案显著增加了复合材料中的温度变化量（p < 0.05）。
当在有2毫米厚牙本质底层的窝洞中单独光固化粘结层时，与3秒高辐照相比，10秒固化方案下能量的放热释放导致温度更高。但是，当随后光固化2毫米厚的复合层时，两种固化方案在髓顶位置产生的最终温度相似，因此，通过超高辐照方案固化的先前粘结剂光聚合不会对牙髓造成更大危害。
