Statement of problem

Facial scanning systems have been developed as auxiliary tools for diagnosis and planning in dentistry. However, little is known about the trueness of these free software programs and apps for facial scanning.

Purpose

The purpose of this in vitro study was to evaluate the trueness of 3D facial scanning by using Bellus3D and +ID ReCap Photo.

Material and methods

A mannequin head was used as the master model. The control group was created by scanning the mannequin head with a noncontact structured blue light 3D scanner (ATOS Core). Two facial scanning methods were used for the experimental groups: a facial scanning app (FaceApp) and the Plus identity photogrammetry methodology (ReCap Photo). In both methods, image capturing was performed under the same natural lighting conditions with a smartphone (iPhone X) calibrated with an app. Trueness was assessed from the 3D measurement error, which was calculated with a 3D mesh analysis software program (GOM Inspect). Two comparison groups were created: ATOS versus Bellus3D (B3D) and ATOS versus +ID with ReCap Photo (+IDRP). The results were statistically evaluated by using the Shapiro-Wilk and paired t tests (α=.05).

Results

B3D had a greater error than +IDRP in measuring the regions of the upper and lower lips, nose, and mentum (P<.01). This error was statistically higher for +IDRP (P<.01) in the right face area, but the left face area showed no statistically significant difference between the evaluated scanning methods (P=.93). The 3D global trueness of B3D was 0.34 ±0.14 mm, and that of +IDRP was 0.28 ±0.06 mm.

Conclusions

Both methods evaluated in this study provided a 3D model of the face with clinically acceptable trueness and should be reliable tools for planning esthetic restorations.

中文翻译：

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2 个面部扫描系统的 3D 误差评估：体外分析

问题陈述

面部扫描系统已被开发为牙科诊断和规划的辅助工具。然而，人们对这些用于面部扫描的免费软件程序和应用程序的真实性知之甚少。

目的

这项体外研究的目的是通过使用 Bellus3D 和 +ID ReCap Photo 评估 3D 面部扫描的真实性。

材料与方法

人体模型头被用作主模型。对照组是通过使用非接触式结构蓝光 3D 扫描仪 (ATOS Core) 扫描人体模型头部而创建的。实验组使用了两种面部扫描方法：面部扫描应用程序 (FaceApp) 和 Plus 身份摄影测量方法 (ReCap Photo)。在这两种方法中，图像捕获都是在相同的自然光照条件下使用经过应用程序校准的智能手机 (iPhone X) 进行的。真实度是根据 3D 测量误差评估的，该误差是使用 3D 网格分析软件程序 (GOM Inspect) 计算得出的。创建了两个比较组：ATOS 与 Bellus3D (B3D) 以及 ATOS 与 +ID with ReCap Photo (+IDRP)。使用 Shapiro-Wilk 和配对t检验 (α=.05) 对结果进行统计评估。

结果

B3D 在测量上下唇、鼻子和下巴区域时比 +IDRP 有更大的误差 ( P <.01)。对于右脸区域的 +IDRP ( P <.01)，该误差在统计学上更高，但左脸区域在评估的扫描方法之间没有统计学上的显着差异 ( P =.93)。B3D 的 3D 全局真实度为 0.34 ±0.14 mm，+IDRP 为 0.28 ±0.06 mm。

结论

本研究中评估的两种方法都提供了具有临床可接受真实性的面部 3D 模型，应该是规划美学修复的可靠工具。