title: Effect of recombinant human bone morphogenetic protein-2 on mandibular distraction at different rates in an experimental model.
abstract: This study evaluates the effect of recombinant human (rh) bone morphogenetic protein (BMP)-2 on mandibular distraction at normal and rapid distraction rates. This study also determines the feasibility of compensating for the increased distraction rate by the addition of rhBMP-2 while maintaining the quality of the distraction regenerate. Twenty-four New Zealand white rabbits were divided into 2 groups, 1 treated at a normal distraction rate (0.9 mm/d) and the other at a rapid distraction rate (2.7 mm/d). At the end of the active distraction period, rhBMP-2 was injected into distraction regenerate, and the contralateral side was used as a control. The distraction regenerates were analyzed by plain radiography, microcomputed tomography, and mechanical testing. The results showed that rhBMP-2 can promote bone formation at both rapid and normal distraction rates. At week 2 and week 4 of consolidation, bone volumes in the BMP-injection sides were significantly higher than in the control sides, but no statistically significant difference was observed between the BMP-injection sides of the rapid and normal distraction groups. At week 8 of consolidation, mechanical testing demonstrated no significant difference of the failure load and stiffness between the BMP-injection and control sides. In conclusion, the study indicates that rhBMP-2 can enhance bone ossification at both normal and rapid distraction rates. The addition of rhBMP-2 can compensate for the rapid distraction rate in mandibular distraction osteogenesis. However, in the long term, the bone quality and stiffness of the distraction regeneration was not influenced by rhBMP-2.
authors.affiliation: Discipline of Oral & Maxillofacial Surgery, Faculty of Dentistry, the University of Hong Kong, SAR, China. lkcheung@hkucc.hku.hk
authors.forename: Lim Kwong
authors.initials: LK
authors.lastname: Cheung
authors.forename: Li Wu
authors.initials: LW
authors.lastname: Zheng
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D001861:Bone Regeneration / Q000187:drug effects* / Q000502:physiology; D016723:Bone Remodeling / Q000187:drug effects / Q000502:physiology; D004195:Disease Models, Animal; D004548:Elasticity; D005240:Feasibility Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008334:Mandible / Q000187:drug effects / Q000503:physiopathology / Q000601:surgery*; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology; D019857:Osteogenesis, Distraction / Q000379:methods*; D011817:Rabbits; D011994:Recombinant Proteins; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta