1 Department of Biotechnology, Middle East Technical University, Ankara, Turkey.
2 Department of Engineering Sciences, Middle East Technical University, Ankara, Turkey.
J Biomater Appl. 2019 Jan;33(6):834-853. doi: 10.1177/0885328218812487. Epub 2018 Nov 20.
Every year, many dental restoration methods are carried out in the world and most of them do not succeed. High cost of these restorations and rejection possibility of the implants are main drawbacks. For this reason, a regenerative approach for repairing the damaged dentin-pulp complex or generating a new tissue is needed. In this study, the potential of three-dimensional cellulose acetate/oxidized pullulan/gelatin-based dentin-like constructs containing 10 or 20% bioactive glass nanoparticles was studied to explore their potential for dentin regeneration. Three-dimensional nano biocomposite structures were prepared by freeze-drying/metal mold pressing methods and characterized by in vitro degradation analysis, water absorption capacity and porosity measurements, scanning electron microscopy, in vitro biomineralization analysis. During one-month incubation in phosphate buffered saline solution at 37°C, scaffolds lost about 25-30% of their weight and water absorption capacity gradually decreased with time. Scanning electron microscopy examinations showed that mean diameter of the tubular structures was about 420 µm and the distance between walls of the tubules was around 560 µm. Calcium phosphate precipitates were formed on scaffolds surfaces treated with simulated body fluid, which was enhanced by boron-modified bioactive glass addition. For cell culture studies human dental pulp stem cells were isolated from patient teeth. An improvement in cellular viability was observed for different groups over the incubation period with the highest human dental pulp stem cells viability on B7-20 scaffolds. ICP-OES analysis revealed that concentration of boron ion released from the scaffolds was between 0.2 and 1.1 mM, which was below toxic levels. Alkaline phosphatase activity and intracellular calcium amounts significantly increased 14 days after incubation with highest values in B14-10 group. Von Kossa staining revealed higher levels of mineral deposition in these groups. In this work, results indicated that developed dentin-like constructs are promising for dentin regeneration owing to presence of boron-modified bioactive glass nanoparticles.
每年，全球都有许多牙科修复方法，但大多数都未能成功。这些修复方法成本高，而且种植体可能被排斥，这是主要的缺点。因此，需要一种修复受损牙本质牙髓复合体或产生新组织的再生方法。在这项研究中，研究了含有 10%或 20%生物活性玻璃纳米粒子的三维醋酸纤维素/氧化普鲁兰/明胶基牙本质样构建体的潜力，以探索其在牙本质再生方面的潜力。通过冷冻干燥/金属模具压制方法制备三维纳米生物复合材料结构，并通过体外降解分析、吸水率和孔隙率测量、扫描电子显微镜、体外生物矿化分析进行表征。在 37°C 的磷酸盐缓冲盐溶液中孵育一个月期间，支架损失了约 25-30%的重量，吸水率随时间逐渐降低。扫描电子显微镜检查表明，管状结构的平均直径约为 420 µm，管的壁之间的距离约为 560 µm。在模拟体液处理的支架表面上形成了磷酸钙沉淀物，硼改性生物活性玻璃的添加增强了这一点。对于细胞培养研究，从患者牙齿中分离出人牙髓干细胞。在孵育期间，不同组的细胞活力都有所提高，其中 B7-20 支架上的人牙髓干细胞活力最高。ICP-OES 分析显示，支架释放的硼离子浓度在 0.2 和 1.1 mM 之间，低于毒性水平。碱性磷酸酶活性和细胞内钙离子含量在孵育 14 天后显著增加，B14-10 组的含量最高。Von Kossa 染色显示这些组的矿物质沉积水平更高。在这项工作中，结果表明，由于存在硼改性生物活性玻璃纳米粒子，开发的牙本质样构建体有望用于牙本质再生。
