Cai Mingkai, Ratnayake Jithendra, Cathro Peter, Gould Maree, Ali Azam
Faculty of Dentistry, Sir John Walsh Research Institute, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
Nanomaterials (Basel). 2022 Nov 7;12(21):3925. doi: 10.3390/nano12213925.
This study aimed to develop injectable chitosan oligosaccharide (COS) and bovine hydroxyapatite (BHA) hybrid biocomposites, and characterise their physiochemical properties for use as a dental pulp-capping material. The COS powder was prepared from chitosan through hydrolytic reactions and then dissolved in 0.2% acetic acid to create a solution. BHA was obtained from waste bovine bone and milled to form a powder. The BHA powder was incorporated with the COS solution at different proportions to create the COS-BHA hybrid biocomposite. Zirconium oxide (ZrO) powder was included in the blend as a radiopacifier. The composite was characterised to evaluate its physiochemical properties, radiopacity, setting time, solubility, and pH. Fourier-transform infrared spectroscopic analysis of the COS-BHA biocomposite shows the characteristic peaks of COS and hydroxyapatite. Compositional analysis via ICP-MS and SEM-EDX shows the predominant elements present to be the constituents of COS, BHA, and ZrO. The hybrid biocomposite demonstrated an average setting time of 1 h and 10 min and a pH value of 10. The biocomposite demonstrated solubility when placed in a physiological solution. Radiographically, the set hybrid biocomposite appears to be more radiopaque than the commercial mineral trioxide aggregate (MTA). The developed COS-BHA hybrid biocomposite demonstrated good potential as a pulp-capping agent exhibiting high pH, with a greater radiopacity and reduced setting time compared to MTA. Solubility of the biocomposite may be addressed in future studies with the incorporation of a cross-linking agent. However, further in vitro and in vivo studies are necessary to evaluate its clinical feasibility.
本研究旨在开发可注射的壳寡糖（COS）与牛羟基磷灰石（BHA）复合生物复合材料，并表征其物理化学性质，以用作牙髓盖髓材料。COS粉末通过壳聚糖水解反应制备，然后溶解于0.2%的乙酸中制成溶液。BHA取自废弃牛骨并研磨成粉末。将BHA粉末与COS溶液按不同比例混合，制成COS-BHA复合生物复合材料。在混合物中加入氧化锆（ZrO）粉末作为射线阻射剂。对该复合材料进行表征，以评估其物理化学性质、射线阻射性、凝固时间、溶解性和pH值。对COS-BHA生物复合材料进行傅里叶变换红外光谱分析，显示出COS和羟基磷灰石的特征峰。通过电感耦合等离子体质谱（ICP-MS）和扫描电子显微镜-能谱分析（SEM-EDX）进行成分分析，结果表明主要元素为COS、BHA和ZrO的成分。该复合生物复合材料的平均凝固时间为1小时10分钟，pH值为10。将该生物复合材料置于生理溶液中时表现出溶解性。在放射影像学上，凝固后的复合生物复合材料似乎比市售的矿物三氧化物聚合物（MTA）具有更高的射线阻射性。所开发的COS-BHA复合生物复合材料作为一种盖髓剂具有良好的潜力，表现出高pH值，与MTA相比具有更高的射线阻射性和更短的凝固时间。生物复合材料的溶解性问题可在未来研究中通过加入交联剂来解决。然而，还需要进一步的体外和体内研究来评估其临床可行性。
