Lu Wen-Ju, Chen Wei-Cheng, Srimaneepong Viritpon, Chen Chiang-Sang, Huang Chang-Hung, Lin Hui-Ching, Tung Oi-Hong, Huang Her-Hsiung
Department of Dentistry, National Yang Ming Chiao Tung University, Taipei 112, Taiwan.
Department of Medicine, MacKay Medical College, New Taipei City 252, Taiwan.
Polymers (Basel). 2023 Jun 17;15(12):2720. doi: 10.3390/polym15122720.
Polyetheretherketone (PEEK) is an emerging thermoplastic polymer with good mechanical properties and an elastic modulus similar to that of alveolar bone. PEEK dental prostheses for computer-aided design/computer-aided manufacturing (CAD/CAM) systems on the market often have additives of titanium dioxide (TiO) to strengthen their mechanical properties. However, the effects of combining aging, simulating a long-term intraoral environment, and TiO content on the fracture characteristics of PEEK dental prostheses have rarely been investigated. In this study, two types of commercially available PEEK blocks, containing 20% and 30% TiO, were used to fabricate dental crowns by CAD/CAM systems and were aged for 5 and 10 h based on the ISO 13356 specifications. The compressive fracture load values of PEEK dental crowns were measured using a universal test machine. The morphology and crystallinity of the fracture surface were analyzed by scanning electron microscopy and an X-ray diffractometer, respectively. Statistical analysis was performed using the paired -test (α = 0.05). Results showed no significant difference in the fracture load value of the test PEEK crowns with 20% and 30% TiO after 5 or 10 h of aging treatment; all test PEEK crowns have satisfactory fracture properties for clinical applications. Fracture surface analysis revealed that all test crowns fractured from the lingual side of the occlusal surface, with the fracture extending along the lingual sulcus to the lingual edge, showing a feather shape at the middle part of the fracture extension path and a coral shape at the end of the fracture. Crystalline analysis showed that PEEK crowns, regardless of aging time and TiO content, remained predominantly PEEK matrix and rutile phase TiO. We would conclude that adding 20% or 30% TiO to PEEK crowns may have been sufficient to improve the fracture properties of PEEK crowns after 5 or 10 h of aging. Aging times below 10 h may still be safe for reducing the fracture properties of TiO-containing PEEK crowns.
聚醚醚酮（PEEK）是一种新兴的热塑性聚合物，具有良好的机械性能，其弹性模量与牙槽骨相似。市场上用于计算机辅助设计/计算机辅助制造（CAD/CAM）系统的PEEK牙科修复体通常含有二氧化钛（TiO₂）添加剂以增强其机械性能。然而，模拟长期口腔内环境的老化与TiO₂含量相结合对PEEK牙科修复体断裂特性的影响鲜有研究。在本研究中，使用两种市售的分别含有20%和30% TiO₂的PEEK块体，通过CAD/CAM系统制作牙冠，并根据ISO 13356规范进行5小时和10小时的老化处理。使用万能试验机测量PEEK牙冠的压缩断裂载荷值。分别通过扫描电子显微镜和X射线衍射仪分析断裂表面的形态和结晶度。采用配对t检验（α = 0.05）进行统计分析。结果显示，经过5小时或10小时老化处理后，含20%和30% TiO₂的测试PEEK牙冠的断裂载荷值无显著差异；所有测试PEEK牙冠在临床应用中均具有令人满意的断裂性能。断裂表面分析表明，所有测试牙冠均从咬合面的舌侧断裂，断裂沿舌沟延伸至舌边缘，在断裂延伸路径的中部呈羽毛状，在断裂末端呈珊瑚状。结晶分析表明，无论老化时间和TiO₂含量如何，PEEK牙冠主要仍为PEEK基体和金红石相TiO₂。我们可以得出结论，在PEEK牙冠中添加20%或30%的TiO₂可能足以在老化5小时或10小时后改善PEEK牙冠的断裂性能。10小时以下的老化时间对于降低含TiO₂的PEEK牙冠的断裂性能可能仍然是安全的。
