title: Evaluation of autogenous PRGF+β-TCP with or without a collagen membrane on bone formation and implant osseointegration in large size bone defects. A preclinical in vivo study.
abstract: OBJECTIVE
  The aim of this study was to evaluate whether the adjunctive use of a collagen membrane enhances bone formation and implant osseointegration in non-contained defects grafted with chair-side prepared autologous platelet-rich growth factor (PRGF) adsorbed on a β-TCP particulate carrier.
  
  
  METHODS
  Large box-type defects (10 × 6 mm; W × D) were prepared in the edentulated and completely healed mandibles of six Beagles dogs. An implant with moderately rough surface was placed in the center of each defect leaving the coronal 6 mm of the implant not covered with bone. The remaining defect space was then filled out with chair-side prepared autologous PRGF adsorbed on β-TCP particles and either covered with a collagen membrane (PRGF/β-TCP+CM) (6 defects) or left without a membrane (PRGF/β-TCP) (5 defects).
  
  
  RESULTS
  Histology 4 months post-op showed new lamellar and woven bone formation encompassing almost entirely the defect and limited residual β-TCP particles. Extent of osseointegration of the previously exposed portion of the implants varied, but in general was limited. Within the defect, new mineralized bone (%) averaged 43.2 ± 9.86 vs. 39.9 ± 13.7 in the PRGF/β-TCP+CM and PRGF/β-TCP group (P = 0.22) and relative mineralized bone-to-implant contact (%) averaged 26.2 ± 16.45 vs. 35.91 ± 24.45, respectively (P = 0.5). First, bone-to-implant contact from the implant top was 4.1 ± 1.5 and 3.2 ± 2.3 (P = 0.9), in the PRGF/β-TCP+CM and PRGF/β-TCP group, respectively.
  
  
  CONCLUSIONS
  Implantation of chair-side prepared autologous PRGF adsorbed on a β-TCP carrier in non-contained peri-implant defects resulted in large amounts of bone regeneration, but osseointegration was limited. Provisions for GBR with a collagen membrane did not significantly enhance bone regeneration or implant osseointegration.
authors.affiliation: Department of Preventive Dentistry, Periodontology & Implant Biology, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Leonidas
authors.initials: L
authors.lastname: Batas
authors.affiliation: Department of Periodontology, Faculty of Odontology, Malmö University, Malmö, Sweden.|Center for Experimental and Preclinical Biomedical Research (CEPBR), Athens, Greece.
authors.forename: Andreas
authors.identifier: http://orcid.org/0000-0001-8161-3754
authors.initials: A
authors.lastname: Stavropoulos
authors.affiliation: Companion Animal Clinic, School of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Serafim
authors.initials: S
authors.lastname: Papadimitriou
authors.affiliation: Stereology and Electron Microscopy, Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Jens R
authors.initials: JR
authors.lastname: Nyengaard
authors.affiliation: Department of Preventive Dentistry, Periodontology & Implant Biology, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Antonios
authors.initials: A
authors.lastname: Konstantinidis
mesh_terms: D000818:Animals; D000077214:Becaplermin; D002130:Calcium Phosphates / Q000494:pharmacology*; D003094:Collagen; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D004285:Dogs; D016557:Guided Tissue Regeneration, Periodontal; D008334:Mandible / Q000601:surgery; D008567:Membranes, Artificial; D023421:Models, Animal; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis / Q000187:drug effects*; D020574:Proto-Oncogene Proteins c-sis / Q000494:pharmacology*
chemical_list: D002130:Calcium Phosphates; D015921:Dental Implants; D008567:Membranes, Artificial; D020574:Proto-Oncogene Proteins c-sis; C485817:beta-tricalcium phosphate; D000077214:Becaplermin; D003094:Collagen
keywords: animal; growth factors; implants; osseointegration; platelet-rich growth factor; β-TCP