Shely Asaf, Lugassy Diva, Anufriev Maxim, Nissan Joseph, Rauchwerger Olisya, Ben-Izhack Gil
Department of Oral Rehabilitation, The Maurice and Gabriela Goldschleger School of Dental Medicine, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.
Department of Orthodontics, The Maurice and Gabriela Goldschleger School of Dental Medicine, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel.
Dent J (Basel). 2024 Mar 4;12(3):61. doi: 10.3390/dj12030061.
This study compared the influence of crystallization on marginal gap adaptation by using computer-aided design and manufacturing (CAD-CAM) for producing monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns.
A total of 25 plastic teeth were scanned using a Primescan intra-oral scanner (IOS), and ZLS crowns were ground. For each unit (abutment and crown), the marginal gap was evaluated pre crystallization and post crystallization at four regions of interest through the use of a scanning electron microscope (SEM). To compare the marginal gap between the two groups, a Kolmogorov-Smirnov test performed on the study variables indicated a normal distribution ( > 0.05) followed by paired samples T-tests (α = 0.0005).
After crystallization, there were significantly higher circumferential marginal gaps (CMGs) for all four surfaces (distal ( = 0.0005), mesial ( = 0.0005), palatal ( = 0.0005), and buccal ( = 0.0005)). The total mean marginal gap (MMG) revealed a significantly higher result for the post-crystallization group (79.82 ± 7.86 μm) compared to the pre-crystallization group (24.25 ± 5.49 μm).
The post-crystallization group showed a significantly higher marginal gap compared to the pre-crystallization group in all parameters, but both groups were in the clinically accepted threshold (<120 microns). In terms of the marginal gap, it is arguable whether to carry out post-crystallization for CELTRA DUO crowns and achieve better mechanical properties but significantly increase the marginal gap.
本研究通过计算机辅助设计与制造（CAD-CAM）制作整体式氧化锆增强硅酸锂（ZLS）陶瓷冠，比较了结晶对边缘间隙适应性的影响。
使用Primescan口腔内扫描仪（IOS）对25颗塑料牙进行扫描，并制作ZLS冠。对于每个单元（基牙和牙冠），通过扫描电子显微镜（SEM）在四个感兴趣区域评估结晶前和结晶后的边缘间隙。为比较两组之间的边缘间隙，对研究变量进行的柯尔莫哥洛夫-斯米尔诺夫检验表明数据呈正态分布（>0.05），随后进行配对样本T检验（α = 0.0005）。
结晶后，所有四个表面（远中面（= 0.0005）、近中面（= 0.0005）、腭面（= 0.0005）和颊面（= 0.0005））的周向边缘间隙（CMG）均显著增大。总平均边缘间隙（MMG）显示，结晶后组（79.82 ± 7.86μm）明显高于结晶前组（24.25 ± 5.49μm）。
结晶后组在所有参数上的边缘间隙均显著高于结晶前组，但两组均处于临床可接受阈值（<120微米）内。就边缘间隙而言，对于CELTRA DUO冠是否进行结晶处理以获得更好的机械性能但显著增加边缘间隙，存在争议。
