由於幾丁聚醣具有良好的生物適應性、抗菌性、和生物可分解性，此研究利用幾丁聚醣製備具有組織整合性和細胞阻擋性的引導組織再生支架，期望能夠應用於治療牙周病所導致的齒槽骨缺損問題。
研究中成功的使用兩階段相分離法製備出不對稱幾丁聚醣支架，由掃描式電子顯微鏡的觀察，可發現支架之不對稱性（上層結構的孔洞小於1μm，而下層結構的的孔洞約在80~120μm），此外，支架亦具有良好的連通性。由細胞穿透性的實驗可得知，上層結構的微小孔洞可以阻擋牙齦纖維母細胞(gingival fibroblast)的通過，然不致對組織液的質傳產生阻礙，而下層結構的大型孔洞，則可以提供足夠的空間供給齒槽骨細胞生長，其效果皆達四個月以上，符合臨床應用的要求。由細胞培養的結果得知，相較於商業化引導組織再生支架和具緻密皮層的幾丁聚醣支架，發現骨細胞在不對稱幾丁聚醣支架上表現較高的活性和骨表現型，即此幾丁聚醣支架之生物親和性較商業化之組織再生膜材較佳。從幾丁聚醣抗菌性和去乙醯度進行分析，在四個月的浸潤之後，幾丁聚醣的抗菌性仍維持優越的表現。综合以上結果，此非對稱幾丁聚醣支架具備有良好的抗菌性、生物相容性、細胞阻擋性和空間創造性，在齒槽骨再生的應用具有相當的潛力。

Chitosan was used in this study to fabricate asymmetric scaffolds for the guided tissue regeneration (GTR) in the treatment of periodontal diseases. With the two-step phase separation, the lacy structure was formed by liquid-liquid demixing on the top layer of scaffolds, where the pore size was about 1 um. On the other hand, the pores on the bottom layer were cellular and ranged from 80 to 120um, which were formed by the formation of ice crystals. From the culture of osteoblastic cells, the tissue integration, cell occlusivity and space-making effect of the novel chitosan scaffold were all excellent for four months; meanwhile, the transport of tissue fluid would not be hindered by the top layer with small pores. Compared with commercial PLLA GTR membranes and chitosan scaffolds with dense skin, the asymmetric chitosan scaffold developed in this research significantly expressed better biocompatibility and osteoconductivity. The anti-bacterial activity of the asymmetric chitosan scaffold would also last at least for four months. From above results, the asymmetric chitosan scaffold was proved to be a potential GTR membrane for the regeneration of alveolar bones.

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