| 摘要: | β-三鈣磷酸鹽（β-TCP）是一種已被用於臨床多年的骨傳導性材料。過去有許多研究指出，二氧化矽在骨礦化中發揮了重要作用且可以提高植入物的生物相容性。在第一個研究中，分別在β-TCP中添加入不同濃度(0、10、20、和30％)的二氧化矽在1400°C下 。
β-tricalcium phosphate (β-TCP) is an osteoconductive material which has been used for clinical purposes for several years. Earlier reports revealed that silica played an important role in bone mineralization and its incorporation would enhance the biocompatibility of the implants. In this study, a series of silica doping ranging from 0, 10, 20, and 30 wt% was performed. Si-β-TCP was obtained upon calcining the as-prepared powders at 1400 °C. To check its effectiveness, the different Si-β-TCP samples were prepared to make new bioactive and biodegradable biocomposites for bone repair. Formation of bone-like apatite, the diametral tensile strength, ions released and weight loss of composites were considered before and after immersion in simulated body fluid (SBF). In addition, we also examined the behavior of human dental pulp cell (hDPCs) cultured on these materials. The results showed that the apatite deposition ability of the β-TCP was enhanced as the Si content was increased. For composites with more than 20% Si contents, the apatite layer covered the samples. At the end of the immersion point, weight losses of 52%, 45%, 33%, and 26% were observed for the β-TCP containing 0%, 10%, 20%, and 30% Si, respectively. In vitro cell experiments shows that the Si-rich cement promote human dental pulp cells (hDPCs) proliferation and differentiation. However, when the Si quantity in the cement is more than 20%, the amount of cells and osteogenesis protein of hDPCs were stimulated by Si released from Si-β-TCP. In addition, polycaprolactone (PCL) has already been approved for a number of medical and drug delivery devices. In this study we have incorporated various concentrations of β-TCP into PCL with the aim of developing an injectable, mechanically strong, and biodegradable material which can be used for medical purposes without organic solvents. This study assesses the physical and chemical properties of this material, evaluates the in vitro bioactivity of the PCL/β-TCP composites, and analyzes cell proliferation and osteogenic differentiation when using human bone marrow mesenchymal stem cells (hBMSCs). The results show that weight losses of approximately 5.3%, 12.1%, 18.6%, and 25.2%, were observed for the TCP0, TCP10, TCP30, and TCP50 composites after immersion in SBF for 12 weeks, respectively, indicating significant differences (p < 0.05). In addition, PCL/β-TCP composites tend to have lower contact angles (47° ± 1.5° and 58° ± 1.7° for TCP50 and TCP30, respectively) than pure PCL (85° ± 1.3°), which are generally more hydrophilic. After 7 days, a significant (22% and 34%) increase (p < 0.05) in the ALP level was measured for TCP30 and TCP50 in comparison with the pure PCL. The degradation of β-TCP and osteogenesis of Si gives strong reason to believe that these Si-based cements may prove to be promising bone repair materials. PCL/TCP is biocompatible with hBMSCs. It not only promotes hBMSCs proliferation but also helps to differentiate reparative hard tissue. We suggest 50 wt% PCL-containing β-TCP biocomposites as the best choice for hard tissue repair applications. |
