Department of Biotechnology, Middle East Technical University, Ankara 06800, Turkey.
Department of Engineering Sciences, Middle East Technical University, Ankara 06800, Turkey; BIOMATEN, CoE in Biomaterials and Tissue Engineering, METU, Ankara 06800, Turkey.
Mater Sci Eng C Mater Biol Appl. 2019 Jul;100:928-948. doi: 10.1016/j.msec.2019.03.022. Epub 2019 Mar 8.
Dental caries is a dental disease affecting public health, which results in many socio-economic consequences. This disease causes loss of tooth hard tissue and subsequent inflammation and loss of the dental pulp. In this study, it was aimed to develop and characterize boron (B) modified bioactive glass nanoparticles (BG-NPs) containing cellulose acetate/oxidized pullulan/gelatin (CA/ox-PULL/GEL) three dimensional scaffolds with tubular morphology for dentin regeneration. 3D nanobiocomposite structures were prepared by thermally induced phase separation and porogen leaching methods and characterized by in vitro degradation analysis, water absorption (WA) capacity measurement, SEM, in vitro biomineralization analysis, porosity measurement and mechanical tests. Scaffolds lost about (30-40)% of their weight during one month and WA capacity decreased with increase in immersion time in phosphate buffer solution (PBS) during one month. According to SEM, aligned and tubular structures were formed with mean diameter of about 11 μm, and BG-NPS were distributed evenly in all parts of the scaffolds. Scaffolds (without BG-NPs) possessed the highest porosity percentage. Addition of 10% BG-NPs improved the mechanical properties of scaffolds. Scaffolds surfaces were fully covered by calcium phosphate (Ca-P) deposits after conditioning in simulated body fluid for 14 days with higher quantity of deposition in groups with inclusion of B-BG-NPs. Human dental pulp stem cells (hDPSCs) were isolated from third molar teeth and used in cell culture studies. In all groups, cells adhered well 1 day after culture. Group B14-10 showed a slight increase of proliferation than group (without BG-NPs) after 7 days of incubation. Alkaline phosphatase activity (ALP) and intracellular calcium amounts increased significantly 14 days after incubation with highest values in B14-10 and B14-20 groups. Confocal laser scanning microscopy (CSLM) analysis, showed that cells on B14-10 and B21-10 scaffold groups, spread more 14 days after culture, and they also possessed extended processes specific to odontoblasts. Alizarin Red quantification showed that the highest calcium deposition was observed on B14-10 scaffolds. Immunohistochemical and Von Kossa stainings showed that scaffolds positively affected the odontoblastic differentiation of the hDPSCs. In this work, results showed that boron modified BG-NPs (B-BG-NPs) incorporated dentin-like constructs bring a new approach for dental tissue engineering applications.
龋齿是一种影响公众健康的牙科疾病，会导致许多社会经济后果。这种疾病会导致牙体硬组织丧失，随后引发炎症和牙髓丧失。本研究旨在开发和表征硼（B）改性生物活性玻璃纳米颗粒（BG-NPs）载体制备具有管状形态的纤维素醋酸酯/氧化普鲁兰/明胶（CA/ox-PULL/GEL）三维支架用于牙本质再生。通过热致相分离和致孔剂浸出法制备 3D 纳米生物复合材料结构，并通过体外降解分析、吸水率（WA）测量、SEM、体外生物矿化分析、孔隙率测量和力学测试进行表征。支架在一个月内损失了约（30-40）%的重量，WA 容量随着在磷酸盐缓冲溶液（PBS）中浸泡时间的增加而在一个月内逐渐降低。根据 SEM 结果，形成了具有约 11 µm 平均直径的排列和管状结构，并且 BG-NPS 均匀分布在支架的各个部分。没有添加 BG-NPs 的支架具有最高的孔隙率百分比。添加 10% BG-NPs 可提高支架的机械性能。支架表面在模拟体液中培养 14 天后完全被磷酸钙（Ca-P）沉积物覆盖，其中包含 B-BG-NPs 的组的沉积量更高。从第三磨牙中分离出人牙髓干细胞（hDPSCs）并用于细胞培养研究。在所有组中，培养 1 天后细胞均良好贴壁。与不含 BG-NPs 的组相比，B14-10 组在孵育 7 天后的增殖略有增加。孵育 14 天后，碱性磷酸酶活性（ALP）和细胞内钙含量显著增加，B14-10 和 B14-20 组的含量最高。共聚焦激光扫描显微镜（CSLM）分析显示，培养 14 天后，B14-10 和 B21-10 支架组的细胞扩散更多，并且它们还具有牙本质细胞特有的延伸过程。茜素红定量显示，B14-10 支架上观察到的钙沉积最高。免疫组织化学和Von Kossa 染色显示，支架对 hDPSCs 的牙本质分化有积极影响。在这项工作中，结果表明，硼改性 BG-NPs（B-BG-NPs）掺入牙本质样构建体为牙科组织工程应用带来了新的方法。
