Immunohistochemical analysis of reconstructed sheep mandibles: transport distraction osteogenesis versus autogenous bone grafting.
OBJECTIVE
Although many studies have been conducted that related to growth factor expression in mandibular distraction osteogenesis, to our knowledge, no study comparing the immunohistochemical outcomes of autologous bone grafting (ABG) and transport distraction osteogenesis has been conducted up to now. The aim of this study was to histologically and immunohistochemically analyze newly formed bone in the resected mandible reconstructed by transport distraction osteogenesis and iliac crest bone grafting in a sheep model.


METHODS
Mandibular discontinuity defects created in the jaws of sheep were reconstructed by distraction osteogenesis (n = 7) and bone grafting (n = 7) and allowed to heal for 3 mos. The animals were then sacrificed and their jaws resected and prepared for decalcification. Histological and immunohistochemical examinations of transforming growth factor-beta 1 (TGF-β1) and bone morphogenetic protein (BMP) -2, -4 were performed in the newly formed bone in the defect area.


RESULTS
Positive staining for BMP-2, -4, and TGF-β was observed in the cells and matrix components. BMP is present in both processes, but the expression of BMP-2, -4, and TGF-β in the distraction regenerate is stronger when compared with bone graft healing.


CONCLUSIONS
The only limitation of the present study was that it evaluated the role of BMP-2, -4, and TGF-β expressions in bone repair process at 3 mo postoperatively. Determination of growth factor expression at more than 1 time point would be ideal in elucidating the role of these factors during bone healing.
Gaziosmanpaşa University, School of Medicine, Clinic of Oral and Maxillofacial Surgery, Tokat, Turkey. nfozkan@hotmail.com
Nilüfer
N
Çakır-Özkan
Ahmet
A
Eyibilen
Fatih
F
Özkan
Mustafa Yavuz
MY
Gülbahar
Yonca Betül
YB
Kabak
D000818:Animals; D001857:Bone Matrix / Q000473:pathology; D055396:Bone Morphogenetic Protein 2 / Q000032:analysis; D055415:Bone Morphogenetic Protein 4 / Q000032:analysis; D001861:Bone Regeneration / Q000502:physiology; D016723:Bone Remodeling / Q000502:physiology; D016025:Bone Transplantation / Q000379:methods*; D003094:Collagen / Q000032:analysis; D003238:Connective Tissue / Q000473:pathology; D005347:Fibroblasts / Q000473:pathology; D007150:Immunohistochemistry; D008297:Male; D008334:Mandible / Q000473:pathology / Q000601:surgery*; D008336:Mandibular Diseases / Q000473:pathology / Q000601:surgery; D023421:Models, Animal; D010006:Osteoblasts / Q000473:pathology; D010011:Osteocytes / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D019857:Osteogenesis, Distraction / Q000379:methods*; D019651:Plastic Surgery Procedures / Q000379:methods*; D012756:Sheep; D053773:Transforming Growth Factor beta1 / Q000032:analysis; D014182:Transplantation, Autologous; D014945:Wound Healing / Q000502:physiology
D055396:Bone Morphogenetic Protein 2; D055415:Bone Morphogenetic Protein 4; D053773:Transforming Growth Factor beta1; D003094:Collagen