목적: Skin wounds may result from various factors such as physical, surgical, or thermal damage, while mouth ulcers, also known as aphthae, manifest on the mucous membrane of the oral cavity. Widely prevalent, mouth ulcers can be linked to numerous diseases and diverse mechanisms. Hydrogels endowed with antioxidant properties have proven to substantially elevate the standard of care by fostering efficient wound healing and tissue regeneration. N- acetylcysteine (NAC), an antioxidant amino acid derivative, emerges as a promising agent for promoting complete tissue restoration. However, its application necessitates further refinement for specific contexts. This study endeavors to scrutinize the impact of a thermosetting N- acetylcysteine hydrogel on both wound healing and oral ulcers. Recognizing the multifaceted nature of the healing process, we aim to compare the effects of this hydrogel in facilitating the intricate sequence of activities associated with tissue restoration. 방법:The N-acetylcysteine (NAC) hydrogel was formulated through the combination of NAC with methylcellulose. Its thermos-gelation properties were evaluated upon exposure to 37º C. Cell viability was compared with existing commercial product using human fibroblast cells. To investigate the impact of the NAC hydrogel on dermal wound and oral ulcer healing, Sprague-Dawley rats served as the experimental model. The study included saline, NAC solution, and a pre-existing commercial NAC product for comparative purposes. Circular full-thickness skin defects were induced on the dorsal region of the animals, with subsequent application of samples every two days. Chemically-induced oral ulcers were introduced through intra-mucosal injection of acetic acid solution, and samples were similarly applied every two days. Over the course of one week, wound and oral ulcer morphology were documented and measured. Tissue samples were subsequently extracted and sectioned for comprehensive histological analyses. 결과:After evaluating various formulations, it was determined that a solution of N-acetylcysteine (NAC) can be efficiently combined with 1% methylcellulose to form a thermogelling material. In vitro assessments indicated that NAC concentrations exceeding 10% led to cell detachment, emphasizing the superior outcomes achieved with lower concentrations. Furthermore, an increased methylcellulose concentration did not yield additional benefits. Consequently, a solution containing 5% NAC and 1% methylcellulose was selected for in vivo testing. Observations from macro images and wound size measurements revealed modest enhancements in wound healing with the routine application of the thermogelling NAC hydrogel over the one-week period. However, noteworthy improvements were evident in oral ulcer healing in rats, as depicted by images and dimensional measurements. Histological examination unveiled fully regenerated mucosal tissue with minimal submucosal fibrous tissue formation in oral ulcers treated with the NAC hydrogel. 결론:The findings suggest that enhanced tissue regeneration can be achieved through the modification of viscosity, thereby improving the retention of N-acetylcysteine (NAC) on the surfaces of wounds and oral ulcers. This aligns with earlier research indicating that the topical application of antioxidants yields beneficial effects on damaged tissues.