Statement of problem

Three-dimensional (3D) printing technologies commonly used for trial complete dentures use photopolymerizing resins. Although effective, some clinical, process-related, and practical issues associated with them are still unclear. The option of using alternative printing technologies may help in overcoming limitations.

Purpose

The purpose of this in vitro study was to evaluate the trueness of trial dentures fabricated by using 3D-printing fused deposition modeling (FDM).

Material and methods

Ten maxillary and 10 mandibular digital complete trial dentures designed from intraoral scans were fabricated from polylactic acid by using a FDM 3D-printer. Each denture was scanned, and the scans were compared with the digital file of the designed denture by means of a surface-matching software program. The mean distance (both signed and absolute) was measured and recorded for the intaglio surface, as well as for the entire denture surface. Statistical analysis was performed to investigate the significance of the extent of measured distances, as well as differences between intaglio and global deviations; subgroup analysis for arch type was also performed (α=.05).

Results

Mean values of the intaglio distance were not significantly different from zero (P=.223). The manufacturing accuracy of the intaglio surface was higher than that measured for the entire denture (P<.001), confirmed both by the averaged signed (0 mm and -0.028 mm, respectively) and the absolute mean deviations (0.06 mm and 0.08 mm, respectively). No significant differences were found between maxillary and mandibular trial dentures.

Conclusions

3D-printing may constitute a valid and practical option for accurate and affordable digital trial dentures.

中文翻译：

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使用熔融沉积建模 3 维打印制造的试验全口义齿的准确性：一项体外研究

问题陈述

通常用于试用全口义齿的三维 (3D) 打印技术使用光聚合树脂。尽管有效，但与它们相关的一些临床、过程相关和实际问题仍不清楚。使用替代印刷技术的选择可能有助于克服限制。

目的

这项体外研究的目的是评估使用 3D 打印熔融沉积建模 (FDM) 制造的试验义齿的真实性。

材料与方法

10 个上颌和 10 个下颌数字化完整试验义齿通过使用 FDM 3D 打印机由聚乳酸制成，通过口内扫描设计。每个义齿都经过扫描，并通过表面匹配软件程序将扫描结果与设计义齿的数字文件进行比较。测量并记录凹版表面以及整个义齿表面的平均距离（带符号的和绝对的）。进行统计分析以研究测量距离范围的重要性，以及凹版和全局偏差之间的差异；还对足弓类型进行了亚组分析 (α=.05)。

结果

凹版距离的平均值与零没有显着差异 ( P =.223)。凹版表面的制造精度高于整个义齿的制造精度 ( P <.001)，由平均符号（分别为 0 毫米和 -0.028 毫米）和绝对平均偏差（分别为 0.06 毫米和 0.08 毫米）证实， 分别）。上颌和下颌试验义齿之间未发现显着差异。

结论

3D 打印可能构成准确且负担得起的数字试验义齿的有效且实用的选择。