Department of Medical Biophysics, Faculty of Medicine in Hradec Králové, Charles University, Hradec Králové, Czech Republic.
Acta Medica (Hradec Kralove). 2022;65(2):59-65. doi: 10.14712/18059694.2022.19.
Due to a broad spectrum of endodontic rotary instruments on the market and no standardised protocol for comparing their mechanical properties, it can be challenging for clinician to choose proper instruments. In vitro studies using resin blocks with artificial canals can offer many valuable information because of their uniformity compared to studies performed on extracted teeth. To improve precision and reproducibility of artificial canals, 3D printing was used in this study to manufacture endodontic test block samples. 20 commercially available endodontic blocks Endo-Training-Bloc-J by Dentsply Sirona were tested. The mean values of the measured parameters were used for a 3D CAD model of their replicas. 20 copies of the endodontic training blocks were printed from acrylic resin (VeroClear-RGD810, Stratasys, Eden Prairie, USA) using the 3D printer Objet30 Pro (Stratasys, Eden Prairie, USA). The key dimensions of the commercial blocks and the 3D printed blocks were measured under and compared using t - test and Levene's test for equality of variances. The profiles of the 3D printed artificial canals showed significantly lower dimensional variability when compared with the commercial blocks. 3D polyjet printing proved to be a precise and reproducible method for production of blocks for testing endodontic rotary instruments.
由于市场上有广泛的根管旋转器械，并且没有用于比较其机械性能的标准化方案，因此临床医生选择合适的器械可能具有挑战性。使用具有人工根管的树脂块进行的体外研究由于与在提取的牙齿上进行的研究相比具有均匀性，因此可以提供许多有价值的信息。为了提高人工根管的精度和可重复性，本研究使用 3D 打印来制造根管测试块样本。测试了 20 个市售的根管训练块 Endo-Training-Bloc-J（登士柏西诺德）。测量参数的平均值用于其复制品的 3D CAD 模型。使用 3D 打印机 Objet30 Pro（Stratasys，Eden Prairie，USA），从丙烯酸树脂（VeroClear-RGD810，Stratasys，Eden Prairie，USA）打印了 20 个根管训练块的副本。使用 t 检验和方差相等的莱文检验测量商用块和 3D 打印块的关键尺寸，并进行比较。与商用块相比，3D 打印人工根管的轮廓显示出明显更低的尺寸可变性。3D 喷射打印被证明是一种用于测试根管旋转器械的块的精确且可重复的生产方法。
