目的: 定量评价集成压缩气流系统扫描头辅助口内三维扫描仪(intraoral 3D scanners, IOS)获取的液体干扰表面数据精度，为集成压缩气流系统扫描头的临床应用提供精度数据。方法: 选择《YY/T 1818—2022牙科学口腔数字印模仪》中标准模型作为扫描对象，利用ATOS Q 12M得到三维扫描数据，作为扫描正确度评价的真值。基于现有扫描仪结构，研究设计了一种新型扫描方案，以解决液体导致IOS精度下降的问题。设计新型扫描头，并集成扫描系统与压缩气流系统，实现口内三维扫描仪在液体干扰表面的高精度数据采集。以常规标准扫描方式作为对照组，探究扫描镜头遮挡、气流、液体介质、新型扫描头对扫描过程及精度的影响，并设置4组实验，且每组扫描15次，以评价基于压缩气流系统扫描头辅助IOS获取液体干扰表面的精度数据。选用Elite和Primescan两款扫描仪作为精度数值的参考。结果: 在正确度和精密度两方面评价中，被液体干扰表面的扫描精度显著下降[正确度：18.5(6.5) vs. 38.0(6.7), P < 0.05;精密度：19.1(8.5) vs. 31.7(15.0), P < 0.05]；使用集成压缩气流系统的新型扫描头辅助口内三维扫描仪，扫描精度显著提升[正确度：22.3(7.6) vs. 38.0(6.7), P < 0.05;精密度：25.8(9.6) vs. 31.7(15.0), P < 0.05]。结论: 集成压缩气流系统的扫描头可以辅助提高IOS液体干扰表面数据的精度。

Objective: To quantitatively evaluate the accuracy of data obtained from liquid-interference surfaces using an intraoral 3D scanner (IOS) integrated with a compressed airflow system, so as to provide clinical proof of accuracy for the application of the compressed airflow system-based scanning head in improving data quality on liquid-interference surfaces. Methods: The study selected a standard model as the scanning object, adhering to the "YY/T 1818—2022 Dental Science Intraoral Digital Impression Scanner" guidelines, a standard that defined parameters for intraoral scanning. To establish a baseline for accuracy, the ATOS Q 12M scanner, known for its high precision, was used to generate true reference values. These true values served as the benchmark for evaluating the IOS performance. Building on the design of an existing scanner, a new scanning head was developed to integrate with a compressed airflow system. This new design aimed to help the IOS capture high-precision data on surfaces where liquid-interference, such as saliva, might otherwise degrade scanning accuracy. The traditional scanning method, without airflow assistance, was employed as a control group for comparison. The study included five groups in total, one control group and four experimental groups, to investigate the effects of scanning lens obstruction, airflow presence, liquid media, and the use of the new scanning head on scanning process and accuracy. Each group underwent 15 scans, generating ample data for a robust statistical comparison. By evaluating trueness and precision in each group, the study assessed the impact of the compressed airflow system on the accuracy of IOS data collected from liquid-interference surfaces. Additionally, we selected Elite and Primescan scanners as references for numerical accuracy values. Results: The scanning accuracy on liquid-interference surfaces was significantly reduced in terms of both trueness and precision [Trueness: 18.5 (6.5) vs. 38.0 (6.7), P < 0.05; Precision: 19.1 (8.5) vs. 31.7 (15.0), P < 0.05]. The use of the new scanning head assisted by the compressed airflow system significantly improved the scanning accuracy [Trueness: 22.3(7.6) vs. 38.0 (6.7), P < 0.05; Precision: 25.8 (9.6) vs. 31.7 (15.0), P < 0.05]. Conclusion: The scanning head based on the compressed airflow system can assist in improving the accuracy of data obtained from liquid-interference surfaces by the IOS.