OBJECTIVE To evaluate and compare the viscoelastic properties of dentine and resin-based dental materials by bulk compressive test and the Burgers model. MATERIALS AND METHODS Sound dentine, three resin composites as well as a resin-based cement were prepared into cylindrical specimens (n = 8). A bulk compressive creep test was applied with a constant load of 300 N (23.9 MPa) for 2 h, followed by another 2 h recovery. The maximum strain, creep stain, percentage of recovery and permanent set was measured using a linear variable displacement transducer. The viscoelastic properties were characterized via the Burgers model, and the instantaneous elastic, viscous as well as elastic delayed deformation were separated from the total strain. Data were analysed via ANOVA (or Welch's Test) and Tukey (or Games-Howell Test) with a significance level of 0.05. RESULTS Sound dentine presented the lowest maximum strain, creep strain, permanent set and the highest percentage of recovery, followed by 3 resin composites with comparable parameters, while the cement showed a significantly higher maximum strain, permanent set and lower percentage of recovery (p < 0.001). The Burgers model presented acceptable fits for characterization viscoelastic processes of both dentine and resin-based dental materials. Viscous and elastic delayed strain of dentine was significantly lower than those for tested materials (p < 0.001) with the highest instantaneous elastic strain percentage. Similar viscous and delayed strain was found among the 4 resin-based materials (p > 0.05). SIGNIFICANCE Sound dentine exhibited superior creep stability compared to resin-based dental materials. The viscous deformation in sound dentine could be ignored when loading parallel to dentine tubules.

中文翻译：

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人类牙本质和树脂基牙科材料的整体压缩蠕变和恢复行为。

目的通过整体压缩试验和Burgers模型评估和比较牙本质和树脂基牙科材料的粘弹性。材料与方法将健全的牙本质，三种树脂复合材料以及一种树脂基水泥制成圆柱形样品（n = 8）。在300 N（23.9 MPa）的恒定载荷下进行整体压缩蠕变试验2小时，然后再恢复2小时。使用线性可变位移传感器测量最大应变，蠕变斑，恢复百分比和永久变形。通过Burgers模型表征粘弹性，并从总应变中分离出瞬时弹性，粘性以及弹性延迟变形。数据通过ANOVA（或Welch's检验）和Tukey（或Games-Howell检验）进行分析，显着性水平为0。05.结果健全的牙本质呈现出最低的最大应变，蠕变应变，永久变形和最高的回复率，其次是3种具有可比较参数的树脂复合材料，而水泥显示出明显更高的最大应变，永久变形和更低的回复率（ p <0.001）。Burgers模型为表征牙本质和树脂基牙科材料的粘弹性过程提供了可接受的拟合。牙本质的粘性和弹性延迟应变显着低于瞬时弹性应变百分比最高的被测材料（p <0.001）。在四种基于树脂的材料中发现相似的粘性和延迟应变（p> 0.05）。重要性与基于树脂的牙科材料相比，健全的牙本质具有优异的蠕变稳定性。