title: RhBMP-2 microspheres-loaded chitosan/collagen scaffold enhanced osseointegration: an experiment in dog.
abstract: The purpose of this study is to develop a novel recombinant human bone morphogenetic protein-2 (rhBMP-2) sustained release scaffold for dental implant osseointegration, and to evaluate the effect of this scaffold on promoting bone formation. RhBMP-2 was encapsulated in the poly-D,L-lactide-co-glycolide (PLGA) biodegradable microspheres, which were subsequently dispersed in a chitosan/collagen composite scaffold. This rhBMP-2 microspheres-loaded scaffold (S-MB) was compared with a chitosan/collagen scaffold without microspheres that directly encapsulated rhBMP-2 (S-B) in vitro and in vivo. The microstructure of the new scaffold was examined with scanning electron microscopy. The release profile of rhBMP-2 in vitro was measured at interval periods. The effect of rhBMP-2 encapsulated scaffolds on enhancing bone formation through implantation in dogs' mandibles was identified by histological examination of the regenerated bone after 4 weeks of implantation. Due to PLGA microspheres being loaded, the S-MB exhibited lower values at porosity and swelling rate, as well as a higher effective release dose than that of the S-B. Bone density, bone-implant contact, and bone-fill values measured from dog experiments demonstrated that the S-MB induced bone regeneration more quickly and was timely substituted by new bone. It was concluded that this sustained carrier scaffold based on microspheres was more effective to induce implant osseointegration.
authors.affiliation: Key Lab of Oral Biomedical Engineering (Wuhan University) Ministry of Education, School and Hospital of Stomatology Wuhan University, Wuhan 430079, P.R. China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Shi
authors.forename: Xiangrong
authors.initials: X
authors.lastname: Cheng
authors.forename: Jiawei
authors.initials: J
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Peng
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage* / Q000493:pharmacokinetics; D048271:Chitosan; D003094:Collagen; D003758:Dental Implantation, Endosseous; D004285:Dogs; D006801:Humans; D019344:Lactic Acid; D008297:Male; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D016348:Osseointegration / Q000187:drug effects*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000493:pharmacokinetics; D054457:Tissue Scaffolds
chemical_list: C525718:BMP2 protein, human; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D011994:Recombinant Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D003094:Collagen; D048271:Chitosan