García-Gil Ignacio, Rodríguez Alonso Verónica, López Suárez Carlos, Mosaddad Seyed Ali, Peláez Jesús, Suárez María J
Department of Conservative Dentistry and Bucofacial Prosthesis, Faculty of Odontology, Complutense University of Madrid, Madrid, Spain.
Department of Research Analytics, Saveetha Institute of Medical and Technical Sciences, Saveetha Dental College and Hospitals, Saveetha University, Chennai, India.
BMC Oral Health. 2025 Apr 11;25(1):532. doi: 10.1186/s12903-025-05944-0.
This study aimed to evaluate the influence of different print orientations and external shell thickness on the accuracy of master casts printed with direct light processing (DLP) technology for fixed dental prostheses.
Seventy-two maxillary hollow master casts were printed with a DLP printer from a standard tessellation language (STL) reference file with dental preparations for a single crown and a 3-unit fixed partial denture. Study groups consisted of six groups (n = 12) according to the print orientation (0, 10, and 20 degrees) and the external shell thickness of the cast (2 mm and 4 mm). Each specimen was digitized with a laboratory scanner. Discrepancies between the reference STL and the experimental STL of the printed cast were measured by using the root mean square (RMS) error. Data were statistically analyzed using one-way ANOVA and Tukey's HDS test to evaluate the trueness, and precision was assessed using the Levene test (α = 0.05).
No significant differences were found in the overall trueness and precision between the groups analyzed for the print orientation and the shell thickness. The 2-mm external shell thickness demonstrated the best trueness on selected points.
The print orientation in the range of 0 to 20 degrees and the cast thickness did not influence the overall accuracy of DLP-printed master casts for fixed prostheses with clinically acceptable range values. Trueness was affected by the external shell thickness on selected points.
本研究旨在评估不同打印方向和外壳厚度对采用直接光处理（DLP）技术打印的固定义齿主模型精度的影响。
使用DLP打印机从具有单冠和3单位固定局部义齿牙体预备的标准镶嵌语言（STL）参考文件中打印72个上颌中空主模型。根据打印方向（0度、10度和20度）和模型的外壳厚度（2毫米和4毫米），研究组分为六组（n = 12）。每个标本用实验室扫描仪进行数字化处理。使用均方根（RMS）误差测量打印模型的参考STL与实验STL之间的差异。数据采用单因素方差分析和Tukey's HDS检验进行统计学分析以评估准确性，使用Levene检验评估精密度（α = 0.05）。
在分析的打印方向和外壳厚度组之间，总体准确性和精密度未发现显著差异。2毫米的外壳厚度在选定的点上显示出最佳的准确性。
0至20度范围内的打印方向和模型厚度不会影响DLP打印的固定修复体主模型在临床上可接受的范围内的总体精度。在选定的点上，准确性受外壳厚度的影响。
