Department of Orthodontics, School of Dentistry, Virginia Commonwealth University, Richmond, Va.
Department of General Practice, School of Dentistry, Virginia Commonwealth University, Richmond, Va.
Am J Orthod Dentofacial Orthop. 2022 Jan;161(1):133-139. doi: 10.1016/j.ajodo.2021.01.020.
The study aimed to (1) compare the accuracy and precision of 3-dimensional (3D) printed retainers at various angulations and (2) evaluate the effect of angulation on printing time and the amount of resin consumed.
Using a stereolithography 3D printer, 60 clear retainers were printed at 5 angulations (n = 12, each): 15°, 30°, 45°, 60°, and 90°. Samples for each group were randomly printed in a batch of 6 retainers at all print angulations as print 1 and print 2 cycles. Digital images of the original and printed samples were superimposed. Discrepancies on 8 landmarks were measured by 2 independent examiners, and 0.25 mm was set as the clinically acceptable threshold to determine the accuracy of the retainers.
Deviations ranged from 0.074 mm to 0.225 mm from the reference retainer at the cusp tips and incisal edges at all angulations, falling within the threshold of clinical acceptance. However, smooth surface measurements with deviations up to 0.480 mm were deemed clinically not acceptable. Three-dimensional printing at 15° was estimated to be the most time-efficient, whereas 3D printing at 45° was shown to be the most cost-effective setting.
Three-dimensional printed retainers, using a stereolithography printer, were found to be accurate within 0.25 mm at all print angulations at the cusp tips and incisal edges compared with the digital reference file. Smooth facial surfaces did not meet clinical acceptability. Print angulations were shown to affect the cost and amount of resin used.
本研究旨在：(1) 比较不同角度的 3 维（3D）打印保持器的准确性和精密度；(2) 评估角度对打印时间和树脂消耗的影响。
使用立体光刻 3D 打印机，以 5 种角度（n=12，每组各 12 个）打印 60 个透明保持器：15°、30°、45°、60°和 90°。每组的样本在 6 个保持器的批处理中随机打印，作为打印 1 和打印 2 循环。将原始和打印样本的数字图像进行叠加。由 2 位独立检查者测量 8 个标志点的差异，将 0.25mm 设定为临床可接受的阈值，以确定保持器的准确性。
在所有角度的牙尖和切缘，偏差从 0.074mm 到 0.225mm，均在临床可接受的阈值范围内。然而，表面光滑度测量的偏差高达 0.480mm，被认为在临床不可接受。15°的 3D 打印被估计是最节省时间的，而 45°的 3D 打印则是最具成本效益的设置。
使用立体光刻打印机打印的 3D 保持器，在牙尖和切缘与数字参考文件相比，在所有打印角度下的偏差都在 0.25mm 内，被认为是准确的。光滑的表面不符合临床可接受性。打印角度会影响成本和树脂的使用量。
