title: Hydroxyapatite/polylactide biphasic combination scaffold loaded with dexamethasone for bone regeneration.
abstract: This study presents a novel design of a ceramic/polymer biphasic combination scaffold that mimics natural bone structures and is used as a bone graft substitute. To mimic the natural bone structures, the outside cortical-like shells were composed of porous hydroxyapatite (HA) with a hollow interior using a polymeric template-coating technique; the inner trabecular-like core consisted of porous poly(D,L-lactic acid) (PLA) that was loaded with dexamethasone (DEX) and was directly produced using a particle leaching/gas forming technique to create the inner diameter of the HA scaffold. It was observed that the HA and PLA parts of the fabricated HA/PLA biphasic scaffold contained open and interconnected pore structures, and the boundary between both parts was tightly connected without any gaps. It was found that the structure of the combination scaffold was analogous to that of natural bone based on micro-computed tomography analysis. Additionally, the dense, uniform apatite layer was formed on the surface of the HA/PLA biphasic scaffold through a biomimetic process, and DEX was successfully released from the PLA of the biphasic scaffold over a 1-month period. This release caused human embryonic palatal mesenchyme cells to proliferate, differentiate, produce ECM, and form tissue in vitro. Therefore, it was concluded that this functionally graded scaffold is similar to natural bone and represents a potential bone-substitute material.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Chosun University, Gwangju, Republic of Korea.
authors.forename: Jun-Sik
authors.initials: JS
authors.lastname: Son
authors.forename: Su-Gwan
authors.initials: SG
authors.lastname: Kim
authors.forename: Ji-Su
authors.initials: JS
authors.lastname: Oh
authors.forename: Mark
authors.initials: M
authors.lastname: Appleford
authors.forename: Sunho
authors.initials: S
authors.lastname: Oh
authors.forename: Joo L
authors.initials: JL
authors.lastname: Ong
authors.forename: Kyu-Bok
authors.initials: KB
authors.lastname: Lee
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D001861:Bone Regeneration / Q000187:drug effects*; D018786:Bone Substitutes / Q000737:chemistry*; D001842:Bone and Bones / Q000378:metabolism / Q000648:ultrastructure; D002460:Cell Line; D003907:Dexamethasone / Q000378:metabolism / Q000494:pharmacology*; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D017886:Durapatite / Q000737:chemistry*; D005938:Glucocorticoids / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D008422:Materials Testing; D010006:Osteoblasts / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry*; D013499:Surface Properties; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*; D055114:X-Ray Microtomography
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D004337:Drug Carriers; D005938:Glucocorticoids; D011091:Polyesters; C033616:poly(lactide); D003907:Dexamethasone; D017886:Durapatite