Department of Prosthodontics, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, China (mainland).
Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, National Clinical Research Center of Stomatology, Shanghai, China (mainland).
Med Sci Monit. 2018 May 10;24:3068-3076. doi: 10.12659/MSM.907097.
BACKGROUND Polymer-infiltrated ceramic-network (PICN) dental material is a new and practical development in orthodontics. Sintering is the process of forming a stable solid mass from a powder by heating without melting. The aim of this study was to evaluate the effects of sintering temperature on the mechanical properties of a PICN zirconia dental material. MATERIAL AND METHODS A dense zirconia ceramic and four PICN zirconia dental materials, with varying porosities, were sintered at three different temperatures; 12 PICN zirconia dental materials based on these porous ceramics were prepared, as well as a pure polymer. After the specimen preparation, flexural strength and elastic modulus values were measured using the three-point bending test, and fracture toughness were determined by the single-edge notched beam (SENB) method. The Vickers hardness test method was used with an indentation strength (IS) test. Scanning electron microscopy (SEM) was used to examine the microstructure of the ceramic surface and the fracture surface. RESULTS Mechanical properties of the PICN dental materials, including flexural strength, elastic modulus, fracture toughness, and hardness, were more similar to the properties of natural teeth when compared with traditional dental ceramic materials, and were affected by the density and sintering temperature. SEM showed that the porous ceramic network became cohesive and that the length of cracks in the PICN dental material was reduced. CONCLUSIONS PICN zirconia dental materials were characterized by similar mechanical properties to natural dental tissues, but further studies are required continue to improve the similarities with natural human enamel and dentin.
聚合物渗透陶瓷网络（PICN）牙科材料是正畸学中的一项新的实用发展。烧结是通过加热使粉末形成稳定的固体块而不熔化的过程。本研究旨在评估烧结温度对 PICN 氧化锆牙科材料力学性能的影响。
致密氧化锆陶瓷和四种不同孔隙率的 PICN 氧化锆牙科材料在三种不同温度下烧结；基于这些多孔陶瓷制备了 12 种 PICN 氧化锆牙科材料和一种纯聚合物。在制备完样品后，使用三点弯曲试验测量抗弯强度和弹性模量值，使用单边缺口梁（SENB）法测定断裂韧性。采用压痕强度（IS）试验的维氏硬度试验方法。扫描电子显微镜（SEM）用于检查陶瓷表面和断裂表面的微观结构。
PICN 牙科材料的力学性能，包括抗弯强度、弹性模量、断裂韧性和硬度，与传统牙科陶瓷材料相比更接近天然牙齿的性能，并且受到密度和烧结温度的影响。SEM 显示多孔陶瓷网络变得具有内聚性，并且 PICN 牙科材料中的裂纹长度减少。
PICN 氧化锆牙科材料的力学性能与天然牙组织相似，但需要进一步研究以提高与天然人牙釉质和牙本质的相似性。
