title: Comparison of 2 Different Formulations of Artificial Bone for a Hybrid Implant With a Tissue-Engineered Construct Derived From Synovial Mesenchymal Stem Cells: A Study Using a Rabbit Osteochondral Defect Model.
abstract: Previously, we developed a hybrid implant composed of hydroxyapatite (HA)-based artificial bone coupled with a mesenchymal stem cell (MSC)-based scaffold-free tissue-engineered construct (TEC) and demonstrated its feasibility for osteochondral repair. Beta-tricalcium phosphate (βTCP) may be a promising alternative to HA, as it is a highly biocompatible material and is resorbed more rapidly than HA in vivo.
  
  
  
  A βTCP-based hybrid TEC implant will exhibit superior osteochondral repair when directly compared with an HA-based hybrid implant, as tested using a rabbit osteochondral defect model.
  
  
  
  Controlled laboratory study.
  
  
  
  Osteochondral defects were created in the femoral groove of skeletally mature rabbits. The TEC and artificial bone, using either HA or βTCP with the same porosities and similar mechanical properties, were hybridized and then implanted in the defects. A histological evaluation and microindentation testing were performed for the assessment of repair tissue.
  
  
  
  Osteochondral defects treated with the TEC/βTCP implants showed more rapid subchondral bone repair at 1 month, but the cartilaginous tissue deteriorated over time out to 6 months after implantation. Osteochondral defects treated with the TEC/HA implants maintained good histological quality out to 6 months after implantation and also exhibited better biomechanical properties at 6 months as compared with the TEC/βTCP implants.
  
  
  
  Contrary to our hypothesis, the TEC/HA hybrid implant facilitated better osteochondral repair than did the TEC/βTCP implant. The results of the present study suggest the importance of a stable restoration of subchondral bone for long-term effective osteochondral repair rather than rapid remodeling of subchondral bone.
  
  
  
  This study contributes to the future selection of suitable materials for patients with osteochondral lesions.
authors.affiliation: Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Shimomura
authors.affiliation: Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Moriguchi
authors.affiliation: Biomechanics Laboratory, Department of Mechanical Engineering, Kogakuin University, Tokyo, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Nansai
authors.affiliation: Biomechanics Laboratory, Department of Mechanical Engineering, Kogakuin University, Tokyo, Japan.|Division of Human Mechatronics Systems, Faculty of System Design, Tokyo Metropolitan University, Tokyo, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Fujie
authors.affiliation: Department of Orthopaedic Surgery, Kansai Rosai Hospital, Amagasaki, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Ando
authors.affiliation: Graduate School of Comprehensive Rehabilitation, Osaka Prefecture University, Osaka, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Horibe
authors.affiliation: McCaig Institute for Bone & Joint Health, University of Calgary, Calgary, Alberta, Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Hart
authors.affiliation: Orthopaedic Arthroscopic Surgery International, Milan, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Gobbi
authors.affiliation: Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshikawa
authors.affiliation: Institute for Medical Science in Sports, Osaka Health Science University, Osaka, Japan.|Center for Advanced Medical Engineering and Informatics, Osaka University, Osaka, Japan.
authors.forename: Norimasa
authors.initials: N
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; D017886:Durapatite; D005260:Female; D059630:Mesenchymal Stem Cells; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; D017886:Durapatite
keywords: artificial bone; beta-tricalcium phosphate; hydroxyapatite; mesenchymal stem cell; osteochondral repair; scaffold free