title: Pharmacologic manipulation of postoperative labial wound contraction and midfacial growth in rabbits.
abstract: Recent experimental work has suggested that increased lip pressure and scar contraction following lip repair with wide soft-tissue undermining may, in part, contribute to midfacial growth inhibition. The present study was designed to test this hypothesis through the application of pharmacologic agents reported to minimize scar contraction. Thirty-six 6-week-old rabbits were divided into six groups: unoperated controls, rabbits with surgically created defects left unrepaired (surgical controls), and four groups of rabbits with surgically created defects with lip repair and wide undermining on the maxillary surface. Animals with lip repair received either no injections or labial subcutaneous injections of distilled water (route-of-injection controls), normal saline, or papaverine hydrochloride for 2 weeks postoperatively. Rabbits with lip repair and saline or papaverine injections showed significantly (p less than 0.05) decreased lip pressure, relatively hypotonic orbicularis oris muscle EMG activity on the cleft lip side, and greater anteroposterior facial growth (assessed radiologically) from 2 to 24 weeks postoperatively compared with rabbits with lip repair and postoperatively compared with rabbits with lip repair and no injections or distilled water injections. Preliminary results suggest that wound contraction following lip repair and soft-tissue undermining may contribute to mid-facial growth inhibition, which may be reduced by pharmacologic manipulations in the rabbit model.
authors.affiliation: Department of Anthropology, School of Dental Medicine, University of Pittsburgh, Pa.
authors.forename: M P
authors.initials: MP
authors.lastname: Mooney
authors.forename: M I
authors.initials: MI
authors.lastname: Siegel
authors.forename: D J
authors.initials: DJ
authors.lastname: Hurwitz
authors.forename: H
authors.initials: H
authors.lastname: Edington
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002971:Cleft Lip / Q000503:physiopathology / Q000601:surgery*; D003286:Contracture / Q000517:prevention & control*; D004195:Disease Models, Animal; D004576:Electromyography / Q000187:drug effects; D005152:Facial Muscles / Q000187:drug effects; D005260:Female; D008297:Male; D008445:Maxillofacial Development / Q000187:drug effects*; D010208:Papaverine / Q000494:pharmacology*; D011312:Pressure; D011817:Rabbits; D012965:Sodium Chloride / Q000494:pharmacology; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D012965:Sodium Chloride; D010208:Papaverine