title: Ectopic bone formation associated with recombinant human bone morphogenetic proteins-2 using absorbable collagen sponge and beta tricalcium phosphate as carriers.
abstract: The ectopic bone formation of recombinant human bone morphogenetic protein-2(rhBMP-2) was evaluated using absorbable collagen sponges (ACS) and beta tricalcium phosphate (beta-TCP) as carriers in a rat subcutaneous assay model. Subcutaneous pockets were created on the back of rats. The pockets were implanted with rhBMP-2/ACS, rhBMP-2/beta-TCP, ACS alone, and beta-TCP alone. The rats were sacrificed at 2 or 8 weeks for histological and immunohistochemical evaluation. At 2 weeks, bone formation was evident in both the rhBMP-2/ACS and rhBMP-2/beta-TCP sites. At 8 weeks, the quantity of the new bone with a more advanced stage of remodeling had increased further in the rhBMP-2/beta-TCP sites. However, the newly formed bone observed at 2 weeks was not found in the rhBMP-2/ACS sites. On immunohistochemical observation, osteopontin staining was observed on both the rhBMP-2/ACS (2 weeks) and rhBMP-2/beta-TCP (2 and 8 weeks) sites. Osteocalcin was not detected in any of the samples. The lack of space-providing capacity of ACS may be one of the major factors responsible for its failure to maintain the newly induced bone. Therefore, a carrier for BMPs should provide space for bone formation and maturation during the more advanced healing stages.
authors.affiliation: Department of Periodontology, Research Institute for Periodontal Regeneration, Brain Korea 21 Project for Medical Science, College of Dentistry, Yonsei University, 134 Shinchon-Dong, Seodaemun-gu, Seoul 120752, Republic of Korea.
authors.forename: Chang-Sung
authors.initials: CS
authors.lastname: Kim
authors.forename: Joon-Il
authors.initials: JI
authors.lastname: Kim
authors.forename: Jin
authors.initials: J
authors.lastname: Kim
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jung-Kiu
authors.initials: JK
authors.lastname: Chai
authors.forename: Chong-Kwan
authors.initials: CK
authors.lastname: Kim
authors.forename: Kyoo-Sung
authors.initials: KS
authors.lastname: Cho
mesh_terms: D020341:Absorbable Implants; D000042:Absorption; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D018786:Bone Substitutes / Q000008:administration & dosage / Q000737:chemistry*; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects*; D002130:Calcium Phosphates / Q000737:chemistry*; D002828:Choristoma / Q000473:pathology; D003094:Collagen / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry*; D004343:Drug Implants / Q000008:administration & dosage; D008297:Male; D008422:Materials Testing; D010012:Osteogenesis / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*
chemical_list: C525718:BMP2 protein, human; D001672:Biocompatible Materials; C525720:Bmp2 protein, rat; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D002130:Calcium Phosphates; D004337:Drug Carriers; D004343:Drug Implants; D016212:Transforming Growth Factor beta; C485817:beta-tricalcium phosphate; D003094:Collagen