Murillo-Gómez Fabián, Murillo-Alvarado Federico, Vásquez-Sancho Fabián, Avendaño Esteban, Urcuyo Roberto
Restorative Dentistry Department, School of Dentistry, University of Costa Rica, San Jose, Costa Rica; Dental Materials Research Laboratory (LIMD), School of Dentistry, University of Costa Rica, San Jose, Costa Rica.
Restorative Dentistry Department, School of Dentistry, University of Costa Rica, San Jose, Costa Rica.
J Dent. 2024 Sep;148:105257. doi: 10.1016/j.jdent.2024.105257. Epub 2024 Jul 21.
Evaluate the impact of a "fast" crystallization and simultaneous-glazing on the physicochemical properties of lithium-disilicate CAD/CAM-ceramic.
Lithium-disilicate bars and crowns (IPS e.max CAD, Ivoclar-Vivadent) were divided into four groups (n = 30): WG/F (WG=with glaze/F=fast crystallization), NG/F (NG=no glaze), WG/C (C=conventional crystallization), and NG/C. A liquid/powder glaze system was used (IPS Ivocolor®, Ivoclar-Vivadent). Specimens were crystallized (Programat P310, Ivoclar-Vivadent) using the P161 program for C (approx. 20-25 min), and P165 for F (approx. 14-16 min). Bars (n = 30) underwent three-point bending tests (flexural strength-FS in MPa and modulus of elasticity-E in GPa) using a universal testing machine. Crowns were analyzed via scanning electron microscopy (SEM) after selective etching, and to Raman, FTIR-ATR, and X-ray diffraction (XRD) spectroscopies to assess chemical composition.
For FS, both factors/interaction were statistically significant. C (427.48±42.41 MPa) showed significantly higher values than F (409.82±38.82 MPa). WG (398.32±29.80 MPa) exhibited significantly lower FS than NG (438.21±41.77 MPa). For E data, both factors/interaction were significant. NG (90.28±14.71 GPa) displayed higher E than WG (83.07±5.69 GPa), while C (90.08±12.98 GPa) exhibited higher E than F (83.46±9.40 GPa). NG/C showed the best results for both variables. F groups showed (SEM) porous surfaces and crack-like marks on crystals. FTIR, Raman and XRD spectra confirmed the typical composition of a lithium-disilicate glass ceramic, and some attenuated signals and structural variations (XRD) in WG.
"Fast" crystallization and simultaneous-glazing produced weaker/less-rigid structures with irregular crystals and glassy phases. Simultaneous glazing may have hindered proper thermal distribution during crystallization.
"Fast" crystallization and simultaneous glazing with non-recommended systems, can adversely affect the final properties of lithium disilicate restorations.
评估“快速”结晶和同步上釉对二硅酸锂CAD/CAM陶瓷物理化学性能的影响。
将二硅酸锂棒材和全冠（IPS e.max CAD，义获嘉伟瓦登特公司）分为四组（n = 30）：WG/F（WG = 上釉/F = 快速结晶）、NG/F（NG = 不上釉）、WG/C（C = 传统结晶）和NG/C。使用液/粉釉系统（IPS Ivocolor®，义获嘉伟瓦登特公司）。使用Ivoclar-Vivadent公司的Programat P310型设备，采用P161程序对C组（约20 - 25分钟）和P165程序对F组（约14 - 16分钟）进行结晶处理。对棒材（n = 30）使用万能试验机进行三点弯曲试验（弯曲强度 - FS，单位为MPa；弹性模量 - E，单位为GPa）。对全冠进行选择性蚀刻后通过扫描电子显微镜（SEM）分析，并进行拉曼光谱、傅里叶变换红外光谱 - 衰减全反射（FTIR-ATR）和X射线衍射（XRD）光谱分析以评估化学成分。
对于FS，两个因素/交互作用均具有统计学意义。C组（427.48±42.41 MPa）的值显著高于F组（409.82±38.82 MPa）。WG组（398.32±29.80 MPa）的FS显著低于NG组（438.21±41.77 MPa）。对于E数据，两个因素/交互作用均显著。NG组（90.28±14.71 GPa）的E高于WG组（83.07±5.69 GPa），而C组（90.08±12.98 GPa）的E高于F组（83.46±9.40 GPa）。NG/C组在两个变量上均显示出最佳结果。F组在SEM下显示晶体表面多孔且有裂纹状痕迹。FTIR、拉曼和XRD光谱证实了二硅酸锂玻璃陶瓷的典型成分，并且WG组存在一些信号衰减和结构变化（XRD）。
“快速”结晶和同步上釉产生了结构较弱/刚性较小、晶体不规则且含有玻璃相的结构。同步上釉可能在结晶过程中阻碍了适当的热分布。
使用不推荐的系统进行“快速结晶”和同步上釉会对二硅酸锂修复体的最终性能产生不利影响。
