A study of the normal temporal healing pattern and the mucociliary transport after endoscopic partial and full-thickness removal of nasal mucosa in sheep

The aim of this study was to assess the temporal healing process of nasal epithelium after full-thickness and partial thickness mucosal removal in sheep. Healing was assessed by histologically examining serial biopsies of the healing wounds. The histology assessed the regeneration of epithelium and return of cilia. Mucociliary clearance was measured before and after injury. On day 84 post injury partial thickness injuries had 80.7% (SEM = 10.25) normal epithelium and 68.35% (SEM = 19.2) reciliation. Full-thickness wounds had 64.98% (SEM = 19.17) normal epithelium and 32.96% (SEM = 17.46) reciliation. On day 84 the difference for epithelium regeneration was not significant (P > 0.05), but reciliation was significant (P < 0.05). The baseline mucociliary clearance was 0.84 mm per second (SEM = 0.2) and did not differ significantly from either the partial thickness wound transport rate (2.49 mm/s; SEM = 1.02) or the full-thickness transport rate (0.9 mm/s; SEM = 0.37) (paired t-test P > 0.05). The time period (84 days) for evaluation of reciliation was insufficient, as reciliation appeared to be continuing. The healing process took place over a longer time period than what had been previously reported in the literature and this may account for the symptoms seen in the postoperative period in patients after sinus surgery.