Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative Dentistry and Periodontology, Research Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054 Erlangen, Germany; National and Kapodistrian University of Athens, School of Dentistry, Department of Biomaterials, 2 Thivon Str, 11527, Goudi, Athens, Greece.
Friedrich-Alexander University Erlangen-Nürnberg, Dental Clinic 1 - Operative Dentistry and Periodontology, Research Laboratory for Dental Biomaterials, Glueckstrasse 11, 91054 Erlangen, Germany.
Dent Mater. 2021 Mar;37(3):413-422. doi: 10.1016/j.dental.2020.11.024. Epub 2021 Jan 19.
To investigate the influence of pre-heating different classes of dental resin composites on viscosity and stickiness at five different temperatures.
Six flowable, five conventional packable, and one thermo-viscous bulk-fill resin composites were heated up to 54°C in a plate-plate rheometer to determine their complex viscosity. Normal force measurements were carried out for the six packable materials to determine the unplugging force and unplugging work (stickiness) over the same temperature range. Data were analyzed using Kolmogorov-Smirnoff test, one-way ANOVA and Tukey Post Hoc test with α=0.05 as level of significance.
At 23°C packable composites showed viscosity between 6.75 and 19.14kPas, while flowable composites presented significantly lower viscosities between 1.31 and 2.20kPas. Pre-heating led to a drop of 30-82% in the viscosity of packable materials. The thermo-viscous material dropped to the level of flowables at 45 and 54°C thus behaving as a packable composite at room temperature with flowable-like viscosity at higher temperatures. No statistically significant differences for viscosity were observed among flowable composites at any temperature. The unplugging force decreased for packable composites, while their unplugging work generally increased at elevated temperature. At 23°C unplugging force was measured between 7.50 and 19.18N, while pre-heating up to 54°C led to values between 2.9 and 6.2N. Regarding unplugging work at 23°C the calculated values were between 3.0 and 8.9×10J and at 54°C between 8.8 and 13.0×10J.
Pre-heating significantly reduced viscosity of highly viscous resin composites, while no influence was shown for flowable composites. In general stickiness, measured as unplugging work, increased at elevated temperatures. The thermo-viscous material showed low viscosity comparable to flowable composites at 45 and 54°C, yet its stickiness did not increase significantly compared to the values at 23°C.
研究在五种不同温度下预热不同种类的牙科树脂复合材料对其粘度和粘性的影响。
将六款流动性树脂复合材料、五款常规可压实树脂复合材料和一款热塑粘性块状填充树脂复合材料加热至 54°C，使用平板-平板流变仪测定其复合粘度。对六款可压实材料进行正向力测量，以确定在相同温度范围内的拔出力和拔出功（粘性）。使用 Kolmogorov-Smirnoff 检验、单因素方差分析和 Tukey 事后检验，以 α=0.05 为显著性水平对数据进行分析。
在 23°C 时，可压实复合材料的粘度在 6.75 到 19.14kPas 之间，而流动性复合材料的粘度显著较低，在 1.31 到 2.20kPas 之间。预热使可压实材料的粘度降低了 30-82%。热塑粘性材料在 45°C 和 54°C 下降至流动性材料的水平，因此在室温下表现为可压实复合材料，而在较高温度下表现为类似流动性的粘度。在任何温度下，流动性复合材料的粘度均无统计学差异。可压实复合材料的拔出力降低，而其拔出功在高温下普遍增加。在 23°C 时，拔出力在 7.50 到 19.18N 之间，而预热至 54°C 时，拔出力在 2.9 到 6.2N 之间。关于 23°C 时的拔出功，计算值在 3.0 到 8.9×10J 之间，而在 54°C 时在 8.8 到 13.0×10J 之间。
预热显著降低了高粘度树脂复合材料的粘度，而对流动性复合材料没有影响。一般来说，粘性（以拔出功衡量）在高温下增加。热塑粘性材料在 45°C 和 54°C 时表现出与流动性复合材料相当的低粘度，但与 23°C 时的数值相比，其粘性并没有显著增加。
