Double-layer scaffold for cartilage tissue regeneration

[[abstract]]膝關節損傷中，可分為軟骨與硬骨損傷，其中，軟骨受損非常常見，由於軟骨無末梢神經，導致軟骨損傷後不易發現，且軟骨受 損後導致硬骨以及周圍組織產生病變，出現發炎、疼痛、關節腫脹 僵硬等情形，間接影響硬骨受損。硬骨組織缺損源自外傷、感染、腫瘤切除或先天性骨骼疾病，如果骨組織再生後發生骨折癒合不全 或是大規模骨缺損的情況，則必須進行植骨手術，骨移植分為三類: 自體骨、異體骨、人工骨，現今以人工骨為最，優點是成分與人體骨相似，且製成多孔性以模擬天然骨特性，能提供骨傳導功能，作為骨細胞生長時貼附支架。本研究主要目的為開發新型態的複合式雙層支架，同時具備軟 骨以及硬骨修復之功能，並且以手術植入的方式供組織再生。複合 式支架總共分為上、下兩層，上層為氧化透明質酸，經交聯後注射 於磷酸鈣支架上，下層為冷凍乾燥後原位成型透明質酸(Hyaluronic Acid)並且混合鈣磷酸鹽(TCP, Tricalcium phosphate)作為硬骨組織的 填補物。鈣磷酸鹽支架經由冷凍乾燥後，會產生孔洞，此孔洞相似 於硬骨組織的骨小梁結構，有助於骨母細胞生長，且鈣磷酸鹽支架 由於混合透明質酸所以具有親水性特質，經冷凍乾燥後放入人體可 迅速將骨缺損部位迅速填滿，且貼合缺損部位。[[abstract]]In knee joint injury, it can be divided into cartilage and bone damage.Cartilage damage is very common clinically. Because cartilage has no peripheral nerves, it is difficult to be noticed by patient after cartilage damage. After cartilage damage, the physiological balance of surrounding bone and soft tissues will be changed because of inflammation, which indirectly affect the environment of bones below the cartilage. This often resulting in pain, joint swelling, and stiffness felling, etc., bone defect originate from trauma, infection, tumor resection or congenital bone disease. If the defect site is too large or bone tissue healing incompletely after facture, bone grafting surgery must be performed. Bone grafting is divided into three categories: autologous bone, allogeneic bone and artificial bone. Among them, artificial bone is the most popular used bone graft nowadays. The advantage of artificial bone including similar composition and structure with human bone, porous characteristics for bone conduction, cell attachment, and cells proliferation.The main purpose of this research is to develop a new type of composite double-layer scaffold, which can repair cartilage and hard bone at the same time and implant it into the human body. The composite scaffold is divided into upper and lower layers. The upper layer is oxidized hyaluronic acid, which is cross-linked and injected on the calcium phosphate scaffold. The lower layer is freeze-dried in-situ formed hyaluronic acid and mixed with calcium phosphate (TCP, Tricalcium phosphate) as a filler for bony tissue. After the calcium phosphate scaffold is freeze-dried, it will produce holes, which are like the bone trabecular structure of hard bone tissue, which is conducive to the growth of osteoblasts, and the calcium phosphate scaffold has hydrophilic characteristics due to the mixed hyaluronic acid. After freeze-drying, it can quickly fill up the bone defect and fit the defect when it is put into the human body