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

Abstract

To test whether or not topically administered recombinant human epidermal growth factor (rhEGF) accelerates the early healing phase of oral soft tissue wounds. 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 + rhEGF at concentrations of 1μg/g (EGF1), 10μg/g (EGF10) or 50μg/g (EGF50). 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. Clinically, in comparison with SH, a significantly smaller wound area was observed in groups EGF1 and EGF10 at day 8 (p<0.05). At day 16, wound closure reached 97.8% in group EGF1 compared to 83.2% in group SH, albeit no statistically different. Histologically, at day 8, significantly more GT was observed in group EGF10 compared to all other groups (p<0.05). At day 16, in addition to a higher Ki67-immunolabelling, groups EGF1 and EGF10 demonstrated a significant decrease in GT and IR with more deposition of C compared to the other groups (p<0.05). Application of rhEGF enhanced the early healing of acute oral soft tissue wounds compared to SH, predominantly at concentrations of 1 and 10μg/g.