Objective

This study investigated viscosity and thermal kinetics of 10 selected preheated restorative resin composites and the effect of ultrasound energy on film thickness.

Methods

A range of different resin composites was tested: Charisma Diamond, IPS Empress Direct, Enamel Plus HRi, Essentia, Estelite Omega, Filtek Z100, Filtek Z350 XT, Gradia, TPH Spectrum and VisCalor. A flowable resin composite (Opallis Flow) and two resin cements (RelyX Veneer, Variolink Esthetic LC) also were tested. Viscosity (Pa s) was measured at 37 °C and 69 °C (preheating temperature) using a rheometer. Film thickness (μm) was measured before and after application of ultrasound energy. Temperature loss within resin composite following preheating (°C/s) was monitored. Data were statistically analyzed (α = 0.05).

Results

Viscosity at 69 °C was lower than at 37 °C for all materials except the flowable resin composite. Preheating reduced viscosity between 47% and 92% for the restorative resin composites, which were generally more viscous than the flowable materials. Film thickness varied largely among materials. All preheated resin composites had films thicker than 50 μm without ultrasound energy. Application of ultrasound reduced film thickness between 21% and 49%. Linear and nonlinear regressions did not identify any relationship between filler loading, viscosity, and/or film thickness. All materials showed quick temperature reduction following preheating, showing maximum temperature loss rates after approximately 10 s.

Significance

Distinct restorative resin composites react differently to preheating, affecting viscosity and film thickness. The overall performance of the preheating technique depends on proper material selection and use of ultrasound energy for reducing film thickness.

中文翻译：

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10种预热的恢复性树脂复合材料的粘度和热动力学以及超声能量对薄膜厚度的影响。

目的

这项研究调查了10种选定的预热修复树脂复合材料的粘度和热动力学，以及超声能量对薄膜厚度的影响。

方法

测试了一系列不同的树脂复合材料：魅力钻石，IPS Empress Direct，Enamel Plus HRi，Essentia，Estelite Omega，Filtek Z100，Filtek Z350 XT，Gradia，TPH Spectrum和VisCalor。还测试了可流动的树脂复合材料（Opallis Flow）和两种树脂水泥（RelyX Veneer，Variolink Esthetic LC）。使用流变仪在37℃和69℃（预热温度）下测量粘度（Pa s）。在施加超声能量之前和之后测量膜厚度（μm）。监测预热后树脂复合材料内部的温度损失（°C / s）。对数据进行统计分析（α = 0.05）。

结果

除了可流动的树脂复合材料外，所有材料的粘度在69°C时均低于37°C。预热将恢复性树脂复合材料的粘度降低到47％至92％之间，通常比可流动的材料更粘。薄膜厚度在不同材料之间差异很大。所有预热的树脂复合材料均具有超过50μm的膜且没有超声能。超声的应用将膜厚度降低了21％至49％。线性和非线性回归没有确定填料含量，粘度和/或膜厚度之间的任何关系。所有材料在预热后均显示出快速的温度降低，在约10 s后显示出最大的温度损失率。

意义

不同的恢复性树脂复合材料对预热的反应不同，从而影响粘度和膜厚度。预热技术的整体性能取决于正确的材料选择和使用超声能量来减小膜厚。