Healing kinetics of oral soft tissue wounds treated with recombinant epidermal growth factor: Translation from a canine model

Objective To test whether or not topically administered recombinant human epidermal growth factor (rh EGF ) accelerates the early healing phase of oral soft tissue wounds. Methods One day following the creation of palatal defects ( n  = 6/animal), 14 dogs were allocated to one of the following five groups: spontaneous healing ( SH ), vehicle ointment (V), vehicle ointment + rh EGF at concentrations of 1 μg/g ( EGF 1), 10 μg/g ( EGF 10) or 50 μg/g ( EGF 50). Topical administration of ointments was repeated twice per day until sacrifice at days 8 and 16. Wound area was clinically monitored. Keratinocytes proliferation (Ki67‐immunolabelling), inflammatory response ( IR ) and areas of collagen (C) and granulation tissue ( GT ) were histologically measured. Kruskal–Wallis test with Dunnett correction was used for multiple group statistical comparisons. Results Clinically, in comparison with SH , a significantly smaller wound area was observed in groups EGF 1 and EGF 10 at day 8 ( p  <   0.05). At day 16, wound closure reached 97.8% in group EGF 1 compared to 83.2% in group SH , albeit no statistically different. Histologically, at day 8, significantly more GT was observed in group EGF 10 compared to all other groups ( p  <   0.05). At day 16, in addition to a higher Ki67‐immunolabelling, groups EGF 1 and EGF 10 demonstrated a significant decrease in GT and IR with more deposition of C compared to the other groups ( p  <   0.05). Conclusion Application of rh EGF enhanced the early healing of acute oral soft tissue wounds compared to SH , predominantly at concentrations of 1 and 10 μg/g.