生物支架已被廣泛應用於作為暫時性的細胞外基質，在組織工程及器官重建中扮演著舉足輕重的角色。本研究將以創新方法結合射出成形及傳統粒子析出法製作隆鼻美容上常用的L型鼻支架。
本研究首先以數值計算軟體研究射出成形的流道設計及產品翹曲變形的最佳化。爾後將生醫高分子材料 Poly(lactic-co-glycolic acid) (PLGA) 及致孔劑Sodium Chloride (NaCl) 依比例混練製成生胚，碎料後經由射出成形，將成品浸入去離子水中去除NaCl完成生物多孔性鼻支架。最後進行鼻支架之機械特性、物理特性及降解性質之探討比較。
細胞培養測試部份選擇類骨母細胞 (MG-63 osteoblastlike cells) 培養於L型生物鼻支架上，於4小時、1、4、7天取樣做 3-[4,5-dimethylthiahiazo-2-y1]-2,4-diphenytetrazolium bromide (MTT) 測試，並利用電子顯微鏡 Scanning Electron Microscope (SEM) 觀察其細胞於支架生長情形。結果顯示，使用射出成形/粒子析出法相較於傳統溶劑澆注/粒子析出法在細胞附著及增生上皆較為良好。
綜合結果顯示，本研究方法所製作出來的生物多孔鼻支架具有良好的生物相容性及生物降解性，目標未來植入人體一段時間後生醫材料完全降解無殘留，同時軟骨組織可生長完成，並且取代傳統人工矽橡膠填充物，大幅降低成本。

Three-dimensional porous scaffolds fabricated from biodegradable polymers have been widely used as temporary Extra-Cellular Matrices (ECM) and play a vital role in tissue engineering and in situ tissue reconstruction. This study presents a novel fabrication technique involving injection molding and conventional particulate leaching (IM/PL) to obtain the L-shaped nasal scaffold for rhinoplasty.
The optimal runner design and warpage for injection molding is discussed first in this study. Numerical simulations are performed for the optimal design. Sodium Chloride (NaCl) is mixed with the Poly(lactic-co-glycolic acid) (PLGA) granules using a screwed extruder and used as materials of the scaffold. Subsequently, the L-shaped nasal scaffold is fabricated by injection molding. The product is then immersed in D.I. water to remove NaCl. Mechanical, physical, and degradation properties for the L-shaped nasal scaffold are measured after it is dried.
MG-63 osteoblastlike cells are chosen to conduct cell culture and the 3-[4,5-dimethylthiahiazo-2-y1]-2,4-diphenytetrazolium bromide (MTT) test in the scaffold. Moreover, a Scanning Electron Microscope (SEM) is employed to observe the viability of the cells after 4 hours, 1, 4, and 7 days. Results of the MTT test indicate that cell proliferation is significantly enhanced in scaffold by the IM/PL technique when compared with scaffold manufactured by the solvent casting/particulate leaching technique.
This study can be concluded that the porous nasal scaffold made by the IM/PL method shows the acceptable biocompatibility and degradation. The nasal scaffold may degrade well after surgery and the cartilage tissue may grow well in it. This IM/PL technique may replace the traditional artificial silicone filler and reduce the surgery cost.

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