Alammar Amirah, Att Wael, Beuer Florian
Department of Prosthodontics, University Hospital Berlin Charité, Berlin, Germany.
Founder and Director, The Face Dental Group, Boston, Massachusetts, USA.
J Esthet Restor Dent. 2025 Apr;37(4):1047-1061. doi: 10.1111/jerd.13365. Epub 2024 Dec 8.
The aim of this in vitro study was to evaluate the accuracy of resin-based fixed dental restorations, namely veneers, single crowns, and four-unit fixed partial dental prosthesis (FPDs), using two different 3D printing technologies and polymer-based materials.
A standard maxillary polyurethane jaw model containing prepared teeth was scanned using an intraoral scanner. The generated STL data were used to design the restorations virtually using CAD software. Two 3D printers were utilized for the provisional digital light processing and stereolithography for the castable resin patterns. Each printer produced 10 specimens of each type of restoration, for a total of 80 restorations. The 3D-printed restorations were then 3D scanned using the same intraoral scanner and evaluated for external and internal dimensional accuracy in terms of trueness and precision. A one-way ANOVA and two-sample T-test were implemented to compute the precision (variability between groups) and trueness (with the designed CAD model). A level of statistical significance of p-value < 0.05 was set.
Statistical differences in the external dimensional analysis of the incisors, molars, and four-unit FPD with p-values < 0.001, 0.002, and 0.004, respectively. For the internal dimensional analysis, the overall mean values of trueness ranged between 17 and 52 μm, and the variability was significant.
The external and internal dimensional accuracy values of the 3D-printed fixed dental restorations in this in vitro study in terms of trueness can be clinically accepted after chairside modifications. However, significant variability between the 3D-printed restorations was observed. Further investigations are needed to improve the accuracy of the 3D-printed fixed dental restorations.
In terms of clinical applications, 3D-printed fixed dental restorations produced by both 3D-printing technologies and polymer-based materials achieved acceptable levels of trueness, although some variability was observed. Significant deviations from the CAD model may require further chairside adjustments. Future integration of AI with 3D-printing may further improve the accuracy and efficiency of fixed dental restoration production.
本体外研究旨在评估使用两种不同的3D打印技术和基于聚合物的材料制作的树脂基固定义齿修复体，即贴面、单冠和四单位固定局部义齿（FPD）的准确性。
使用口内扫描仪对含有预备牙的标准上颌聚氨酯颌骨模型进行扫描。生成的STL数据用于使用CAD软件虚拟设计修复体。两台3D打印机分别用于临时数字光处理和立体光刻以制作可铸造树脂模型。每台打印机每种修复体制作10个样本，共80个修复体。然后使用同一台口内扫描仪对3D打印的修复体进行3D扫描，并从准确性和精确性方面评估其外部和内部尺寸精度。采用单因素方差分析和双样本T检验来计算精确性（组间变异性）和准确性（与设计的CAD模型相比）。设定p值<0.05为统计学显著性水平。
切牙、磨牙和四单位FPD的外部尺寸分析存在统计学差异，p值分别<0.001、0.002和0.004。对于内部尺寸分析，准确性的总体平均值在17至52μm之间，且变异性显著。
在本体外研究中，3D打印的固定义齿修复体在准确性方面的外部和内部尺寸精度值在椅旁修改后临床上可以接受。然而，观察到3D打印修复体之间存在显著变异性。需要进一步研究以提高3D打印固定义齿修复体的精度。
在临床应用方面，两种3D打印技术和基于聚合物的材料制作的3D打印固定义齿修复体均达到了可接受的准确性水平，尽管观察到一些变异性。与CAD模型的显著偏差可能需要进一步的椅旁调整。未来人工智能与3D打印的整合可能会进一步提高固定义齿修复体制作的准确性和效率。
