title: Tissue Reaction to a Novel Bone Substitute Material Fabricated With Biodegradable Polymer-Calcium Phosphate Nanoparticle Composite.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effectiveness of a novel bone substitute material fabricated using a biodegradable polymer-calcium phosphate nanoparticle composite.
  
  
  METHODS
  Porous structured poly-L-lactic acid (PLLA) and hydroxyapatite (HA) nanoparticle composite, which was fabricated using solid-liquid phase separation and freeze-drying methods, was grafted into bone defects created in rat calvarium or tibia. Rats were killed 4 weeks after surgery, and histological analyses were performed to evaluate new bone formation.
  
  
  RESULTS
  Scanning electron microscopic observation showed the interconnecting pores within the material and the pore diameter was approximately 100 to 300 μm. HA nanoparticles were observed to be embedded into the PLLA beams. In the calvarial implantation model, abundant blood vessels and fibroblastic cells were observed penetrating into pores, and in the tibia model, newly formed bone was present around and within the composite.
  
  
  CONCLUSIONS
  The PLLA-HA nanoparticle composite bone substitute developed in this study showed biocompatibility, elasticity, and operability and thus has potential as a novel bone substitute.
authors: *PhD Candidate, Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan. †Visiting Professor, Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden. ‡Lecturer, Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan. §Assistant Professor, Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan. ¶Assistant Professor, Section of Bioengineering, Department of Dental Engineering, Fukuoka Dental College, Fukuoka, Japan. ‖Associate Professor, Section of Energy Conversion Engineering, Division of Renewable Energy Dynamics, Research Institute for Applied Mechanics, Kyushu University, Fukuoka, Japan. #Professor, Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hideo
authors: H
authors: Shimizu
authors: Yohei
authors: Y
authors: Jinno
authors: Yasunori
authors: Y
authors: Ayukawa
authors: Ikiru
authors: I
authors: Atsuta
authors: Takaaki
authors: T
authors: Arahira
authors: Mitsugu
authors: M
authors: Todo
authors: Kiyoshi
authors: K
authors: Koyano
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D018786:Bone Substitutes / Q000627:therapeutic use*; D016025:Bone Transplantation / Q000379:methods; D002130:Calcium Phosphates / Q000737:chemistry / Q000627:therapeutic use*; D017886:Durapatite / Q000627:therapeutic use; D008297:Male; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000627:therapeutic use*; D010012:Osteogenesis; D011091:Polyesters / Q000627:therapeutic use; D011108:Polymers / Q000737:chemistry / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000601:surgery; D013977:Tibia / Q000601:surgery
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; D011091:Polyesters; D011108:Polymers; C033616:poly(lactide); D017886:Durapatite; C020243:calcium phosphate