Dai Kang, Wu Jiang, Zhao Zhen, Yu Hai, Zhao Zhe, Gao Bo
State Key Laboratory of Military Stomatology & National Clinical Research Centre for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
School of Material Science and Engineering, Shanghai Institute of Technology, Shanghai 201418, China.
Materials (Basel). 2023 Sep 5;16(18):6072. doi: 10.3390/ma16186072.
Veneered zirconia ceramics are widely used for dental restorations. However, the relatively poor bonding strength between the ceramic core and veneer porcelain remains a common problem in clinical applications. To address this issue, this study focused on enhancing the core-veneer bond strength of zirconia restorations through the implementation of surface textures using digital light processing (DLP) technology. The light intensity was precisely tuned to optimize mechanical strength and minimize light scattering. Subsequently, hexagonal or square grids were printed on the surface of the zirconia ceramic core. Following veneering procedures, the shear bond strength (SBS) test was conducted using a universal testing machine. Dates were compared using analysis of variance (ANOVA) and the least significant difference (LSD) test. Furthermore, optical microscopy and scanning electron microscopy (SEM) were used to examine the failure modes and observe the cross-sectional structures, respectively. The results indicated that the presence of a 0.09 mm high hexagon grid led to a significant 21% increase in the SBS value. However, grids with heights of 0.2 and 0.3 mm showed less improvement, owing to the formation of large defects at the interface during the fusion process. This study demonstrated the potential of DLP technology in preparing zirconia ceramics with complex structures and high mechanical strength, thereby offering promising solutions for overcoming challenges associated with dental applications.
烤瓷氧化锆陶瓷广泛应用于牙齿修复。然而，陶瓷内冠与饰面瓷之间相对较差的粘结强度仍是临床应用中的一个常见问题。为了解决这个问题，本研究聚焦于通过使用数字光处理（DLP）技术实现表面纹理来提高氧化锆修复体的内冠-饰面粘结强度。精确调整光强度以优化机械强度并最小化光散射。随后，在氧化锆陶瓷内冠表面打印六边形或正方形网格。在进行饰面程序后，使用万能试验机进行剪切粘结强度（SBS）测试。使用方差分析（ANOVA）和最小显著差异（LSD）测试对数据进行比较。此外，分别使用光学显微镜和扫描电子显微镜（SEM）检查失效模式并观察横截面结构。结果表明，高度为0.09 mm的六边形网格使SBS值显著提高了21%。然而，高度为0.2和0.3 mm的网格改善较少，这是由于在融合过程中界面处形成了大的缺陷。本研究证明了DLP技术在制备具有复杂结构和高机械强度的氧化锆陶瓷方面的潜力，从而为克服牙科应用相关挑战提供了有前景的解决方案。
