Research Director, Research and Development Department, Eco&Rich dental technology Corp, Seoul, Republic of Korea.
Medical Device Reviewer, National Institute of Food and Drug Safety Evaluation, Osong, Republic of Korea.
J Prosthet Dent. 2024 Mar;131(3):487-493. doi: 10.1016/j.prosdent.2022.01.031. Epub 2022 Mar 16.
Digital light processing (DLP) and milling (MIL) are computer-aided design and computer-aided manufacturing (CAD-CAM) systems that have become popular for fabricating definitive complete dentures. However, few studies have compared the accuracy of the ridge laps of diagnostic tooth arrangements fabricated with these systems and their adaptation with the denture base sockets.
The purpose of this in vitro study was to comparatively analyze the accuracy of the ridge laps of the diagnostic tooth arrangements fabricated by using MIL and different layer thicknesses in DLP.
A virtual definitive complete denture was designed with a CAD software program on a scanned virtual digital cast, divided into diagnostic tooth arrangement and a denture base that accommodated the arrangement, and saved as a standard tessellation language (STL) file. From this file, 27 diagnostic tooth arrangements were fabricated by DLP (50 μm and 100 μm) and MIL. The ridge laps were scanned and overlapped on the file (reference data) to analyze the accuracy (trueness and precision). The ridge laps of all groups were overlapped on the reference denture base data to analyze their adaptation with the sockets. The measurements of the trueness, precision, and adaptation were analyzed statistically by using the nonparametric Kruskal-Wallis test and post hoc Mann-Whitney U test with Bonferroni correction.
The diagnostic tooth arrangements showed significant differences among the groups (P<.001). The values were the lowest in the MIL group and highest in the DLP group for the following parameters: trueness root-mean-square (RMS) value, 173 ±7 μm versus 286 ±15 μm; precision RMS value, 22 ±3 μm versus 57 ±20 μm; and adaptation RMS value, 41 ±5 μm versus 112 ±13 μm.
Of the 2 diagnostic tooth arrangements fabricated with the CAD-CAM systems, the one fabricated with MIL was clinically more appropriate.
数字光处理（DLP）和铣削（MIL）是计算机辅助设计和计算机辅助制造（CAD-CAM）系统，已广泛用于制作最终的全口义齿。然而，很少有研究比较过使用这些系统制作的诊断牙列的牙槽嵴搭接的准确性及其与义齿基托窝的适应性。
本体外研究的目的是比较分析使用 MIL 和 DLP 不同层厚制作的诊断牙列的牙槽嵴搭接的准确性。
使用 CAD 软件程序在扫描的虚拟数字模型上设计虚拟全口义齿，分为诊断牙列和容纳该牙列的义齿基托，并保存为标准三角形语言（STL）文件。从该文件中，通过 DLP（50 μm 和 100 μm）和 MIL 制作了 27 个诊断牙列。扫描牙槽嵴并在文件（参考数据）上重叠以分析准确性（准确性和精密度）。将所有组的牙槽嵴重叠到参考义齿基托数据上，以分析其与窝的适应性。使用非参数 Kruskal-Wallis 检验和事后曼-惠特尼 U 检验（Bonferroni 校正）对准确性、精密度和适应性的测量值进行统计学分析。
各组诊断牙列之间存在显著差异（P<.001）。在 MIL 组中，准确性 RMS 值为 173 ±7 μm，精度 RMS 值为 22 ±3 μm，适应性 RMS 值为 41 ±5 μm，值最低；在 DLP 组中，准确性 RMS 值为 286 ±15 μm，精度 RMS 值为 57 ±20 μm，适应性 RMS 值为 112 ±13 μm，值最高。
在这两种使用 CAD-CAM 系统制作的诊断牙列中，使用 MIL 制作的牙列在临床上更合适。
