목적: Synechia formation and ostial stenosis are the most common complications after endoscopic sinus surgery (ESS). However, synechia formation process has not been fully understood and there is no synechia animal model of nasal mucosa. The present study aimed to establish a synechia model of nasal mucosa and evaluate the effect of dexamethasone on the synechia of nasal mucosa in a mouse. 방법:Unilateral wound in the nasal cavity was induced using interdental brush in 6-week-old C57BL/6 mice. Dexamethasone was administered intranasally and intraperitoneally to experimental groups, respectively. Mice were sacrificed 2, 14 and 28 days after injury. Histopathologic changes were evaluated using hematoxylin and eosin for wound or synechia formation and immunohistochemistry was used for matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 and Transforming growth factor (TGF)-ß1. 결과:The synechia were observed in all mice of control group. However, the number of synechia was reduced by systemic dexamethasone. At early stage, the exudates tend to be reduced in experimental groups. Bone remodeling process was observed in histopathologic examination and bone thickness was reduced by systemic dexamethasone at late stage. Except for TGF-ß1, TIMP-1 and MMP-9 were increased in experimental groups 결론:A synechia model of nasal mucosa was established in a mouse using mechanical injury. Systemic dexamethasones decrease the synechia formation of nasal mucosa in a mouse.