BACKGROUND: Tracheal stenosis constitutes one of the most frequently seen problems in thoracic surgery. Although many treatment modalities to prevent fibroblast proliferation, angiogenesis, or inflammation that causes tracheal stenosis have been attempted, an effective method has not yet been found. In this study, a transforming growth factor beta3 (TGF-beta 3)/chitosan combination was used for this purpose. METHODS: A slow-release preparation containing a thin layer of TGF-beta 3 with a chitosan base was made. Thirty albino Wistar rats were divided into 3 groups. A full-layer vertical incision was made in the anterior side of the trachea of each rat between the second and fifth tracheal rings. The tracheal incision was sutured. Group A was evaluated as the control group. In Group B, a chitosan-based film was placed on the incision line. In Group C, a slow-release TGF-beta/chitosan-coated substance was placed on the incision line. The rats were killed on day 30, and their tracheas were excised by cutting between the lower edge of the thyroid cartilage and the upper edge of the sixth tracheal ring together with the esophagus. Epithelialization, fibroblast proliferation, angiogenesis, inflammation, and collagen levels were evaluated histopathologically by the same histopathologist. RESULTS: Statistically significant differences were not found among the 3 groups. Cold abscesses were observed at the incision sites in both the TGF-beta/chitosan and chitosan groups. These were thought to have formed due to the chitosan. CONCLUSIONS: As this was the first experiment in the literature to use this type of TGF-beta 3 formulation, we intend to change the formulation and perform this study again with a different TGF-beta 3/chitosan preparation.