REPAIR OF NASAL DEFECTS USING COLLAGEN GELS CONTAINING INSULIN-LIKE-GROWTH-FACTOR-1

Objective: Facial osseous defects are a common and challenging problem for the otolaryngologist-head and neck surgeon. Current methods of re pair including synthetic grafts, cadaveric material, and autologous ti ssue have drawbacks of foreign body reaction, infectious agent transmi ssion, and the morbidity of a second surgical site. In the effort to d evelop an ideal technique for osseous reconstruction, a critical-size facial defect has previously been developed in the Sprague-Dawley rat. This model exhibits less than 10% healing by surface area over 6 mont hs. A novel approach to osseous reconstruction is attempted using this model with type I collagen gel augmented with insulin-like growth fac tor 1 (IGF-1). Study Design: Randomized controlled trial using a roden t model. Methods: Twelve adult male Sprague-Dawley rats underwent a su rgical procedure to produce a critical-size nasal defect by removing t he nasal bones with a cutting burr. Six animals were repaired with 300 mu g of type I collagen gel. Six animals were repaired with 300 mu g of type I collagen gel augmented with 3.0 mu g of IGF-1. Thirty days l ater, the animals were examined after necropsy. Precise planimetry, ra diodensitometric analysis, and histologic sectioning were performed. R esults: All animals had a complete coverage of this defect with a thin layer of bone. Radiodensitometric analysis indicated that there was a statistically significant (P < .037) increase in bone density in the collagen plus IGF-1 group compared with that of collagen only. In addi tion, histologic evaluation revealed increased bone density and thickn ess in the IGF-1 group. Conclusion: Type I collagen gel augmented with IGF-1 results in a significant increase in healing of a nasal critica l-size defect in a rodent model.