title: Repair of a rodent nasal critical-size osseous defect with osteoblast augmented collagen gel.
abstract: OBJECTIVE
  Facial skeletal defects are a common challenge for the otolaryngologist. Type I collagen gels have shown promise in the repair of nonhealing critical size defects (CSDs) of facial bone by providing scaffolding for new bone growth by osteoblasts at the defect perimeter. The objective of the present study was to evaluate the effect that suspending osteoblasts within a type I collagen gel has on the repair of a rodent facial CSD.
  
  
  METHODS
  Randomized controlled trial using a rodent model.
  
  
  METHODS
  A previously described facial CSD was created by removing the nasalis bones with a cutting burr to the level of the nasal mucosal membranes on 18 Sprague-Dawley rats. Groups of six animals were treated with an implant containing either 300 microg of type I collagen gel, 12 x 10(5) osteoblasts suspended within type I collagen gel, or 12 x 10(5) fibroblasts suspended within type I collagen gel for comparison. After 30 days the animals-were examined at necropsy with planimetry, histological analysis of new bone growth, and radiodensitometric analysis of bone thickness.
  
  
  RESULTS
  All animals had complete coverage with a thin layer of bone. Histological sectioning revealed an increased thickness in the osteoblast augmented group. Radiodensitometric measurements revealed a statistically significant increase in bone repair in the osteoblast group compared with the collagen-only group (P < or = .0005) and the fibroblast group (P < or = .04).
  
  
  CONCLUSIONS
  Type I collagen gels augmented with an osteoblastic suspension significantly enhance the repair of nasal CSDs in a rodent model. The use of cultured bone precursor cells represents a leap forward in osteoengineering.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Virginia Health Sciences Center, Charlottesville, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Toung
authors.forename: R C
authors.initials: RC
authors.lastname: Ogle
authors.forename: R F
authors.initials: RF
authors.lastname: Morgan
authors.forename: W H
authors.initials: WH
authors.lastname: Lindsey
mesh_terms: D000818:Animals; D018786:Bone Substitutes; D002478:Cells, Cultured; D003094:Collagen; D004195:Disease Models, Animal; D005069:Evaluation Studies as Topic; D005782:Gels; D008297:Male; D009296:Nasal Cavity / Q000601:surgery; D010006:Osteoblasts; D019736:Prostheses and Implants; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D018786:Bone Substitutes; D005782:Gels; D003094:Collagen