PURPOSE: To establish a porcine model for maxillary distraction osteogenesis and to document the sequence of bone formation in the zone of advancement. MATERIALS AND METHODS: Female Yucatan minipigs (n = 9) in the mixed dentition stage underwent modified Le Fort I osteotomy through a vestibular incision under general anesthesia. A unidirectional, semiburied Le Fort I distraction device was fixed across the osteotomy. The distraction protocol was 0-day latency, 1-mm/d rate for 12 days, and 24 days of fixation. Maxillary specimens (n = 9) were harvested and divided in half at the end of distraction (n = 6 sides), midfixation (n = 6), and the end of fixation (n = 6). Clinical stability, volume, and radiographic density across the zone of advancement were graded on semiquantitative scales. Specimens were stained with hematoxylin and eosin and examined with light microscopy. RESULTS: Animals tolerated the operation, the distraction and fixation periods. There were no infections and no devices failed. At the end of the distraction period, bone trabeculae were present at the periphery and fibrous tissues, and vessels, preosteoblasts, and osteoblasts were present in the center of the zone of advancement. Islands of chondrocyte-like cells appeared in 1 specimen each at midfixation and the end of fixation. At the end of fixation, clinical stability and radiographic density were graded 3/3 and bone formation was complete across the advancement zone in all specimens. CONCLUSION: A model for Le Fort I distraction osteogenesis was established. Intramembranous bone formation was the predominant mechanism of healing in the zone of advancement. Latency was not necessary for bone formation in this minipig model.
PURPOSE: To establish a porcine model for maxillary distraction osteogenesis and to document the sequence of bone formation in the zone of advancement. MATERIALS AND METHODS: Female Yucatan minipigs (n = 9) in the mixed dentition stage underwent modified Le Fort I osteotomy through a vestibular incision under general anesthesia. A unidirectional, semiburied Le Fort I distraction device was fixed across the osteotomy. The distraction protocol was 0-day latency, 1-mm/d rate for 12 days, and 24 days of fixation. Maxillary specimens (n = 9) were harvested and divided in half at the end of distraction (n = 6 sides), midfixation (n = 6), and the end of fixation (n = 6). Clinical stability, volume, and radiographic density across the zone of advancement were graded on semiquantitative scales. Specimens were stained with hematoxylin and eosin and examined with light microscopy. RESULTS: Animals tolerated the operation, the distraction and fixation periods. There were no infections and no devices failed. At the end of the distraction period, bone trabeculae were present at the periphery and fibrous tissues, and vessels, preosteoblasts, and osteoblasts were present in the center of the zone of advancement. Islands of chondrocyte-like cells appeared in 1 specimen each at midfixation and the end of fixation. At the end of fixation, clinical stability and radiographic density were graded 3/3 and bone formation was complete across the advancement zone in all specimens. CONCLUSION: A model for Le Fort I distraction osteogenesis was established. Intramembranous bone formation was the predominant mechanism of healing in the zone of advancement. Latency was not necessary for bone formation in this minipig model.
Authors: Jonathan F Bova; Anderson F da Cunha; Rhett W Stout; Sarindr Bhumiratana; David M Alfi; Sidney B Eisig; Gordana Vunjak-Novakovic; Mandi J Lopez Journal: J Invest Surg Date: 2014-11-13 Impact factor: 2.533
Authors: Mohammed Al-Rakan; Jaimie T Shores; Steve Bonawitz; Gabriel Santiago; Joani M Christensen; Gerald Grant; Ryan J Murphy; Ehsan Basafa; Mehran Armand; Pete Otovic; Sue Eller; Gerald Brandacher; Chad R Gordon Journal: J Craniofac Surg Date: 2014-11 Impact factor: 1.046
Authors: Montserrat Caballero; Justin C Morse; Alexandra E Halevi; Omri Emodi; Michael R Pharaon; Jeyhan S Wood; John A van Aalst Journal: Tissue Eng Part C Methods Date: 2015-09 Impact factor: 3.056