Department of Prosthodontics, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Department of Prosthodontics, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
Int Orthod. 2022 Jun;20(2):100641. doi: 10.1016/j.ortho.2022.100641. Epub 2022 May 24.
Different methods are available for making temporary restorations. The purpose of this study was to determine and compare the shear bond strength of orthodontic brackets on temporary crowns made by three different methods.
In this experimental study, disc form samples (N=54) were made in dimensions 8×1mm, according to the manufacturer's instructions. In this study, we had three groups (N=18) based on manufacturing methods (3D printing, conventional, and CAD/CAM). Following surface preparation of the samples, the brackets were bonded in the centre of the discs. Before the shear bond strength test, the samples were subjected to the thermocycling process. The shear bond strength of brackets was measured by Universal Testing Machine. Data were analysed by one-way ANOVA and LSD post hoc test.
The findings indicated that the mean shear bond strength of orthodontic stainless-steel brackets on temporary crowns varied between CAD/CAM and 3D printing methods (P<0.001) and also between CAD/CAM and conventional methods (P<0.001). The mean shear bond strength of orthodontic stainless steel brackets on temporary crowns was not different between 3D printing and conventional methods (P=0.7).
The shear bond strength of orthodontic stainless-steel brackets bonded to temporary crowns fabricated by conventional and 3D printing methods was similar, and the shear bond strength in the samples fabricated by CAD/CAM method was lower than other specimens.
有多种方法可用于制作临时修复体。本研究的目的是确定并比较三种不同方法制作的临时冠上正畸托槽的剪切粘结强度。
在这项实验研究中，根据制造商的说明，制作了尺寸为 8×1mm 的盘状样品（N=54）。在这项研究中，我们根据制造方法（3D 打印、常规和 CAD/CAM）将样本分为三组（N=18）。在对样本表面进行预处理后，将托槽粘在圆盘的中心。在进行剪切粘结强度测试之前，样本要经过热循环处理。使用万能试验机测量托槽的剪切粘结强度。使用单因素方差分析和 LSD 事后检验对数据进行分析。
研究结果表明，CAD/CAM 和 3D 打印方法之间（P<0.001）以及 CAD/CAM 和常规方法之间（P<0.001）正畸不锈钢托槽在临时冠上的平均剪切粘结强度存在差异。3D 打印和常规方法制作的临时冠上正畸不锈钢托槽的平均剪切粘结强度无差异（P=0.7）。
常规和 3D 打印方法制作的临时冠上正畸不锈钢托槽的剪切粘结强度相似，而 CAD/CAM 方法制作的样本的剪切粘结强度低于其他样本。
