title: Use of bone morphogenetic protein-2 and dentin matrix protein-1 to enhance the osteointegration of the Onplant system.
abstract: Onplants are known to provide absolute anchorage for orthodontic tooth movement in humans if loaded after 3 to 4 months, and can be removed after use. The purpose of our study was to evaluate the speed and effectiveness of osteointegration of onplants treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) and/or dentin matrix protein-1 (DMP-1) in rabbits. Fifty-four onplants were placed on the calvaria of 9 rabbits. Onplants were divided into four groups: rBMP-2, rDMP-1, BMP-2 +DMP-1 (B+D), and controls. The hydroxyapatite surface of each onplant was soaked in a solution of the assigned protein in each of the study groups or a phosphate buffer solution in the control group. Onplants were inserted into subperiosteal tunnels and allowed to heal for 6 weeks. After euthanizing the animals, bone blocks, each containing an onplant, were prepared for either histological examination or biomechanical characterization. Histological and histomorphometric results demonstrated significant bone formation at the bone-onplant interface in the BMP-2 and B+D groups when compared with DMP1 and the controls. Mechanically, onplants treated with BMP-2 withstood tensile forces between 3.4 and 5.0 kg. Onplants treated with BMP-2 and DMP1 (B+D) withstood an average of 3 kg of pulling forces. On the other hand, onplants in the DMP1 and control groups withstood forces ranging between 0 kg to 1.3 kg. These results indicate a potential of enhancing the osteointegration of onplants for early loading.
authors.affiliation: Department of Oral Biology, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
authors.forename: Ali H
authors.initials: AH
authors.lastname: Hassan
authors.forename: Carla A
authors.initials: CA
authors.lastname: Evans
authors.forename: A Moneim
authors.initials: AM
authors.lastname: Zaki
authors.forename: Anne
authors.initials: A
authors.lastname: George
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D001842:Bone and Bones / Q000187:drug effects; D016326:Extracellular Matrix Proteins; D006801:Humans; D008297:Male; D016348:Osseointegration / Q000187:drug effects* / Q000502:physiology; D010750:Phosphoproteins / Q000494:pharmacology*; D011817:Rabbits; D011994:Recombinant Proteins; D012886:Skull / Q000187:drug effects / Q000473:pathology; D013314:Stress, Mechanical; D013718:Tensile Strength; D016212:Transforming Growth Factor beta
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; C513309:DMP1 protein, human; D016326:Extracellular Matrix Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2