Effects of osteoinduction on bone regeneration in distraction: results of a pilot study.
Rate and frequency of distraction as well as stimulatory effects transmitted by growth factors and local gene therapy have a decisive influence on bone regeneration. In a pilot study we tested the effect of four different morphogenetic and mitotic proteins and a genetically transferred vector system on bone healing in continuous osteodistraction in a large animal experiment on 24 Goettingen mini-pigs. For this purpose bone morphogenetic protein (BMP-2), BMP-7, TGF-beta, IGF-1 and a liposome vector were instilled into the distraction gap. The animals were killed after 1-4 weeks of consolidation. Histological and radiological evaluations showed maximum bone formation after the application of BMP-2/7, whereas the application of TGF-beta, IGF-1 and the liposomal vector had only a limited effect on bone regeneration. The quantitative analysis demonstrated an average amount of bone in the distraction gap of 50% and 61% after instillation of BMP-2 and 7, respectively. The BMP-2 expression, however, was maximal after induction with the non-viral vector. Only after BMP-2/7 application could physical, radiographic and histological evidence of bone union be detected. In bone distraction with a short observation period the application of morphogenetic proteins seems to enhance bone regeneration significantly. Before application in humans further studies are necessary to measure the dose-effect relationship, the mode of application and the efficacy of different inductive proteins. The combination of osteodistraction with osteoinduction, however, could shorten treatment times dramatically.
Kroczek
A
A
Department of Oral and Maxillofacial Surgery, University Hospitals Erlangen, Glueckstrasse 11, D-91054 Erlangen, Germany.
Park
J
J
Birkholz
T
T
Neukam
F W
FW
Wiltfang
J
J
Kessler
P
P
D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage / Q000235:genetics / Q000502:physiology*; D055419:Bone Morphogenetic Protein 7 / Q000008:administration & dosage / Q000502:physiology; D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology*; D005260:Female; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000008:administration & dosage; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage / Q000502:physiology; D008081:Liposomes / Q000008:administration & dosage*; D008334:Mandible / Q000187:drug effects / Q000502:physiology* / Q000601:surgery; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology; D019857:Osteogenesis, Distraction / Q000379:methods*; D010865:Pilot Projects; D013552:Swine; D013556:Swine, Miniature; D016212:Transforming Growth Factor beta / Q000008:administration & dosage / Q000502:physiology
D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D008081:Liposomes; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I