title: Osseointegration of fiber-reinforced composite implants: histological and ultrastructural observations.
abstract: OBJECTIVE
  The aim of this study was to evaluate the bone tissue response to fiber-reinforced composite (FRC) in comparison with titanium (Ti) implants after 12 weeks of implantation in cancellous bone using histomorphometric and ultrastructural analysis.
  
  
  METHODS
  Thirty grit-blasted cylindrical FRC implants with BisGMA-TEGDMA polymer matrix were fabricated and divided into three groups: (1) 60s light-cured FRC (FRC-L group), (2) 24h polymerized FRC (FRC group), and (3) bioactive glass FRC (FRC-BAG group). Titanium implants were used as a control group. The surface analyses were performed with scanning electron microscopy and 3D SEM. The bone-implant contact (BIC) and bone area (BA) were determined using histomorphometry and SEM. Transmission electron microscopy (TEM) was performed on Focused Ion Beam prepared samples of the intact bone-implant interface.
  
  
  RESULTS
  The FRC, FRC-BAG and Ti implants were integrated into host bone. In contrast, FRC-L implants had a consistent fibrous capsule around the circumference of the entire implant separating the implant from direct bone contact. The highest values of BIC were obtained with FRC-BAG (58±11%) and Ti implants (54±13%), followed by FRC implants (48±10%), but no significant differences in BIC or BA were observed (p=0.07, p=0.06, respectively). TEM images showed a direct contact between nanocrystalline hydroxyapatite of bone and both FRC and FRC-BAG surfaces.
  
  
  CONCLUSIONS
  Fiber-reinforced composite implants are capable of establishing a close bone contact comparable with the osseointegration of titanium implants having similar surface roughness.
authors.affiliation: Department of Oral Health Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, BC, Canada; Dental Implant and Osseointegration Research Chair, College of Dentistry at King Saud University, Riyadh, Saudi Arabia. Electronic address: ahmed.ballo@dentistry.ubc.ca.
authors.forename: A M
authors.initials: AM
authors.lastname: Ballo
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
authors.forename: I
authors.initials: I
authors.lastname: Cekic-Nagas
authors.affiliation: Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
authors.forename: G
authors.initials: G
authors.lastname: Ergun
authors.affiliation: Department of Biomaterials Science and Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
authors.forename: L
authors.initials: L
authors.lastname: Lassila
authors.affiliation: Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Palmquist
authors.affiliation: BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg, Sweden; SP Technical Research Institute Sweden, Borås, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Borchardt
authors.affiliation: BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg, Sweden; SP Technical Research Institute Sweden, Borås, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Lausmaa
authors.affiliation: Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Thomsen
authors.affiliation: Department of Biomaterials Science and Turku Clinical Biomaterials Centre - TCBC, Institute of Dentistry, University of Turku, Turku, Finland.
authors.forename: P K
authors.initials: PK
authors.lastname: Vallittu
authors.affiliation: Department of Prosthetic Dentistry, Institute of Dentistry, University of Turku, Turku, Finland; Clinic of Oral Diseases, Turku University Central Hospital, Turku, Finland.
authors.forename: T O
authors.initials: TO
authors.lastname: Närhi
mesh_terms: D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D000069343:Bone-Implant Interface / Q000033:anatomy & histology; D003188:Composite Resins / Q000737:chemistry*; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D017886:Durapatite / Q000737:chemistry; D005260:Female; D005270:Femur Head / Q000648:ultrastructure*; D005898:Glass / Q000737:chemistry*; D021621:Imaging, Three-Dimensional / Q000379:methods; D055115:Light-Curing of Dental Adhesives / Q000379:methods; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D016348:Osseointegration / Q000502:physiology*; D011092:Polyethylene Glycols / Q000737:chemistry; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry; D011817:Rabbits; D013052:Spectrometry, X-Ray Emission; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D015921:Dental Implants; D003764:Dental Materials; D011109:Polymethacrylic Acids; C403922:bioactive glass S53P4; C009753:fiberglass; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D017886:Durapatite; D014025:Titanium
keywords: Fiber-reinforced composite; Implant; In vivo experiment; Osseointegration