Intra-uterine healing of fetal rat oral mucosal, skin and cartilage wounds.

Orofacial wounds, including rupture of the palate, were surgically created in utero on 19 1/2 day Sprague Dawley rat fetuses. Six hours prior to sacrifice 0.1 mgm/100 gm maternal body weight of colchicine was injected subcutaneously. Five fetuses in each group of operated and unoperated controls were sacrificed at 0, 24, 48 and 72 h postoperatively. Serial histological sections in the frontal plane were stained with hemotoxylin and eosin and modified Mallory's. Rapid and complete epithelialization of oral and skin wounds was observed within the 72 h period. There was a complete lack of inflammatory response, scab formation and involvement of nasal epithelium in healing. Nasal cartilage wounds rapidly rounded off and the perichondrium reformed without evidence of callus formation. These findings are discussed in regard to the etiology of some congenital defects and the prospects of fetal surgical correction of orofacial deformity.