Objectives

Understand how discontinuous short glass fibers and braided long fibers can be effectively used to reinforce a resin modified glass ionomer cement (RMGIC) for carious lesion restorations.

Methods

Two control groups (powder/liquid kit and capsule) were prepared from a light cured RMGIC. Either discontinuous short glass fibers or braided polyethylene fiber ribbons were used as a reinforcement both with and without pre-impregnation with resin. For the former case, the matrix was the powder/liquid kit RMGIC, and for the latter case the matrix was the capsule form. Flexural strength was evaluated by three-point beam bending and fracture toughness was evaluated by the single-edge V-notch beam method. Compressive strength tests were performed on cylindrical samples. Results were compared by analysis of variances and Tukey’s post-hoc test. Flexural strength data were analyzed using Weibull statistical analysis.

Results

The short fiber reinforced RMGIC both with and without pre-impregnation showed a significant increase of ∼50% in the mean flexural strength and 160–220% higher fracture toughness compared with the powder/liquid RMGIC control. Reinforcement with continuous braided fibers gave more than a 150% increase in flexural strength, and pre-impregnation of the braided fibers with resin resulted in a significant flexural strength increase of more than 300% relative to the capsule control. However, for the short fiber reinforced RMGIC there was no significant benefit of resin pre-impregnation of the fibers. The Weibull modulus for the flexural strength approximately doubled for the fiber reinforced groups compared to the control groups. Finally, compressive strength was similar for all the groups tested.

Significance

By using a RMGIC as a matrix, higher flexural strength was achieved compared to reported values for short fiber reinforced GICs. Additionally, the short fibers provided effective toughening of the RMGIC matrix by a fiber bridging mechanism. Finally, continuous braided polyethylene fibers gave much higher flexural strength than discontinuous glass fibers, and their effectiveness was enhanced by pre-impregnation of the fibers with resin.

中文翻译：

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树脂改性的玻璃离聚物水泥的纤维增强

目标

了解不连续的短玻璃纤维和编织的长纤维如何有效地用于增强树脂改性的玻璃离聚物胶粘剂（RMGIC），以修复龋齿。

方法

由光固化的RMGIC制备两个对照组（粉/液盒和胶囊）。不连续的短玻璃纤维或编织的聚乙烯纤维带都可以用作增强材料，既可以使用树脂也可以不使用树脂。对于前一种情况，基质是粉末/液体试剂盒RMGIC，对于后一种情况，基质是胶囊形式。通过三点梁弯曲评估抗弯强度，并通过单边V形缺口梁方法评估断裂韧性。对圆柱形样品进行抗压强度测试。通过方差分析和Tukey事后检验比较结果。使用威布尔统计分析法来分析抗弯强度数据。

结果

与粉末/液体RMGIC对照相比，预浸渍和不预浸渍的短纤维增强RMGIC的平均弯曲强度均显着提高约50％，断裂韧性提高160-220％。连续编织纤维增强的抗弯强度增加了150％以上，并且用树脂对编织纤维进行预浸渍后，相对于胶囊对照组，弯曲强度显着提高了300％以上。但是，对于短纤维增强的RMGIC，树脂对纤维的预浸渍没有明显的好处。与对照组相比，纤维增强组的抗弯强度的威布尔模量大约增加了一倍。最后，所有测试组的抗压强度均相似。

意义

通过使用RMGIC作为基质，与报道的短纤维增强GIC相比，其弯曲强度更高。另外，短纤维通过纤维桥接机制提供了RMGIC基体的有效增韧。最后，连续编织的聚乙烯纤维比不连续的玻璃纤维具有更高的弯曲强度，并且通过用树脂预浸渍纤维增强了其有效性。