Sezer Taygun, Albayrak Haydar, Ayata Mustafa, Yavuz Hasan İsmail, Yamanoğlu Rıdvan
Lecturer, Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
Associate Professor, Department of Prosthodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
J Prosthet Dent. 2025 Aug;134(2):469.e1-469.e8. doi: 10.1016/j.prosdent.2025.05.035. Epub 2025 Jun 23.
The hatch distance, which refers to the spacing between adjacent laser lines in the laser melting process, may influence the microstructure of the metal framework and, hence, the metal-ceramic bond strength. However, studies on the influence of hatch distance on metal-ceramic bond strength are lacking.
The purpose of this in vitro study was to investigate the porcelain bond strength of cobalt chromium frameworks fabricated using selective laser melting with hatch distances of 50 µm, 55 µm, and 60 µm.
Bar-shaped cobalt chromium frameworks were fabricated using selective laser melting with hatch distances of 50 µm (Group-50), 55 µm (Group-55), and 60 µm (Group-60). After porcelain application, the metal-ceramic bond strength was evaluated using a 3-point bend test according to the International Organization for Standardization (ISO) 9693-1 standard. After the 3-point bend test, elemental analysis was performed on both the metal and porcelain interfaces of 1 randomly selected specimen from each group, and the density of 1 metal framework from each group was determined using the Archimedes method. In addition, microstructural analysis was performed on 1 metal framework from each group using optical microscopy, while 1 porcelain-applied metal framework was analyzed using scanning electron microscopy. The metal-ceramic bond strength data were statistically analyzed using a 1-way analysis of variance (α=.05) RESULTS: Hatch distance significantly affected the metal-ceramic bond strength (P<.001). Group-50 exhibited the highest mean ±standard deviation metal-ceramic bond strength (32.99 ±3.17 MPa), which was significantly higher than Group-55 (29.98 ±2.41 MPa; P<.001) and Group-60 (29.33 ±1.83 MPa; P<.001). No significant difference was found between Group-55 and Group-60 (P=.83). The elemental analysis indicated the absence of metal alloy components Co, Cr, Mo, and W on the porcelain side of the fracture interface across all groups. The proportions of porcelain composition elements Si, Ce, Ti, Zr, K, Al, Na, and Ca detected on the metal side of the fracture interface were consistent among the groups. As the hatch distance increased, the density of the frameworks decreased while porosity within the frameworks increased. The densities of Group-50, Group-55, and Group-60 were calculated as 8.28 g/cm³, 8.14 g/cm³, and 8.06 g/cm³, respectively.
The results revealed that hatch distance may affect the metal-ceramic bond strength and microstructure of cobalt chromium frameworks.
孵化距离是指激光熔化过程中相邻激光线之间的间距，它可能会影响金属框架的微观结构，进而影响金属-陶瓷结合强度。然而，关于孵化距离对金属-陶瓷结合强度影响的研究尚缺。
本体外研究的目的是调查使用选择性激光熔化技术制造的钴铬框架在孵化距离为50 µm、55 µm和60 µm时的瓷结合强度。
使用选择性激光熔化技术制造条形钴铬框架，孵化距离分别为50 µm（50组）、55 µm（55组）和60 µm（60组）。涂瓷后，根据国际标准化组织（ISO）9693-1标准，采用三点弯曲试验评估金属-陶瓷结合强度。三点弯曲试验后，对每组随机选取的1个试样的金属和瓷界面进行元素分析，并使用阿基米德法测定每组1个金属框架的密度。此外，对每组1个金属框架进行光学显微镜微观结构分析，对1个涂瓷金属框架进行扫描电子显微镜分析。使用单向方差分析对金属-陶瓷结合强度数据进行统计分析（α = 0.05）。结果：孵化距离显著影响金属-陶瓷结合强度（P <.001）。50组的平均±标准差金属-陶瓷结合强度最高（32.99 ± 3.17 MPa），显著高于55组（29.98 ± 2.41 MPa；P <.001）和60组（29.33 ± 1.83 MPa；P <.001）。55组和60组之间未发现显著差异（P = 0.83）。元素分析表明，所有组的断裂界面瓷侧均未检测到金属合金成分Co、Cr、Mo和W。各组在断裂界面金属侧检测到的瓷组成元素Si、Ce、Ti、Zr、K、Al、Na和Ca的比例一致。随着孵化距离增加，框架密度降低，框架内孔隙率增加。50组、55组和60组的密度分别计算为8.28 g/cm³、8.14 g/cm³和8.06 g/cm³。
结果表明，孵化距离可能会影响钴铬框架的金属-陶瓷结合强度和微观结构。
