Department of Conservative and Preventive Dentistry, Center for Dental Medicine, University of Zurich, Plattenstrasse 11, 8032, Zurich, Switzerland.
Department of Endodontics and Restorative Dentistry, School of Dental Medicine, University of Zagreb, Gunduliceva 5, 10000, Zagreb, Croatia.
Clin Oral Investig. 2023 Jun;27(6):3169-3180. doi: 10.1007/s00784-023-04928-0. Epub 2023 Mar 4.
To assess the behavior of dual-cure and conventional bulk-fill composite materials on real-time linear shrinkage, shrinkage stress, and degree of conversion.
Two dual-cure bulk-fill materials (Cention, Ivoclar Vivadent (with ion-releasing properties) and Fill-Up!, Coltene) and two conventional bulk-fill composites (Tetric PowerFill, Ivoclar Vivadent; SDR flow + , Dentsply Sirona) were compared to conventional reference materials (Ceram.x Spectra ST (HV), Dentsply Sirona; X-flow; Dentsply Sirona). Light curing was performed for 20 s, or specimens were left to self-cure only. Linear shrinkage, shrinkage stress, and degree of conversion were measured in real time for 4 h (n = 8 per group), and kinetic parameters were determined for shrinkage stress and degree of conversion. Data were statistically analyzed by ANOVA followed by post hoc tests (α = 0.05). Pearson's analysis was used for correlating linear shrinkage and shrinkage force.
Significantly higher linear shrinkage and shrinkage stress were found for the low-viscosity materials compared to the high-viscosity materials. No significant difference in degree of conversion was revealed between the polymerization modes of the dual-cure bulk-fill composite Fill-Up!, but the time to achieve maximum polymerization rate was significantly longer for the self-cure mode. Significant differences in degree of conversion were however found between the polymerization modes of the ion-releasing bulk-fill material Cention, which also exhibited the significantly slowest polymerization rate of all materials when chemically cured.
While some of the parameters tested were found to be consistent across all materials studied, heterogeneity increased for others.
With the introduction of new classes of composite materials, predicting the effects of individual parameters on final clinically relevant properties becomes more difficult.
评估双固化和传统块状充填复合材料的实时线性收缩、收缩应力和转化率行为。
将两种双固化块状充填材料（Cention，Ivoclar Vivadent（具有离子释放性能）和 Fill-Up！，Coltene）和两种传统块状充填复合材料（Tetric PowerFill，Ivoclar Vivadent；SDR flow + ，Dentsply Sirona）与传统参考材料（Ceram.x Spectra ST（HV），Dentsply Sirona；X-flow；Dentsply Sirona）进行比较。用光固化 20s 或仅自固化。实时测量 4 小时内的线性收缩、收缩应力和转化率（每组 n=8），并确定收缩应力和转化率的动力学参数。采用方差分析（α=0.05）后进行事后检验对数据进行统计学分析。采用 Pearson 分析对线性收缩和收缩力进行相关分析。
与高粘度材料相比，低粘度材料的线性收缩和收缩应力明显更高。双固化块状充填复合材料 Fill-Up！的聚合模式之间的转化率无显著差异，但自固化模式达到最大聚合速率的时间明显延长。然而，具有离子释放性能的块状充填材料 Cention 的聚合模式之间的转化率存在显著差异，当化学固化时，该材料的聚合速率也是所有材料中最慢的。
虽然测试的一些参数在所有研究材料中表现一致，但其他参数的异质性增加。
随着新型复合材料的出现，预测个别参数对最终临床相关性能的影响变得更加困难。
