Effect of Epidermal Growth Factor on Tympanic Membrane Epithelial Migration in Canine Models

Background: Tympanic membrane epithelial migration (TMEM) protects the external ear canal from infections and aids in the removal of keratin. Epidermal growth factor (EGF) accelerates tissue regeneration by stimulating cell proliferation and migration. Hypothesis/Objectives: Topical application of EGF will accelerate the canine TMEM rate. Animals: Three male beagle dogs. Materials and Methods: Six TMs were divided into control and experimental phases. The experimental phase was assessed 2 weeks after the control phase and involved weekly EGF applications (0.5 mg/mL; 25 μg in 50 μL of phosphate-buffered saline), while the control phase involved no treatment. TMEM was assessed by applying ink spots to the TM and tracking migration on Day (D)0, D7, D14 and D21. A paired Student's t-test was used to compare the daily TMEM rates between phases. Results: The EGF-treated phase had a significantly higher mean TMEM rate (235.0 ± 91.76 μm/day) than the control phase (146.83 ± 69.95 μm/day), showing a 60.1% increase (p < 0.05). The mean difference was 88.2 μm/day (95% confidence interval [CI]: 36.8–139.5). This difference was statistically significant based on both the paired t-test (p = 0.020) and Wilcoxon signed-rank test (p = 0.031). No differences were noted between the left and right ears, and no adverse effects occurred. Conclusions and Clinical Relevance: These results suggest that EGF increases TMEM in dogs. These initial findings suggest potential clinical applications of EGF. Further studies are needed to validate these findings and evaluate their therapeutic potential.