title: Osseointegration and implant stability of extraoral implants in Göttingen minipigs after irradiation.
abstract: OBJECTIVE
  The aim of this study was to compare the influence of implant surface treatment and irradiation dose on implant stability and osseointegration of 144 extraoral implants in irradiated frontal bone of minipigs.
  
  
  METHODS
  144 implants with 3 different surface treatments (machined, etched and HAVD-coated) were implanted in the frontal bone of 16 Göttingen minipigs. Three groups of four pigs received radiation with equivalent doses of 25, 50 and 70 Gy, and one group served as control. Resonance frequency analysis (RFA) was performed recording Implant Stability Quotients (ISQ) at implant placement and 3 months thereafter. Removal torque was measured whilst removing specific implants after 3 months. In addition, the bone-to-implant contact (BIC) was analyzed.
  
  
  RESULTS
  Evaluation of ISQ, BIC-values showed no significant difference between the different surface treatments in irradiated and non-irradiated bone. Removal torque revealed statistically significant differences between machined and HAVD-coated implants in the irradiated bone.
  
  
  CONCLUSIONS
  Implant stability and osseointegration, based on Removal Torque showed significant higher results for the HAVD-coated implants. No significant difference was observed between the irradiated and non-irradiated animals. This study shows that HAVD-coated extraoral implants can potentially be used for craniofacial rehabilitation in non-irradiated and irradiated bone.
authors.affiliation: Department of Cranio-Maxillofacial Surgery and GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands. Electronic address: l.poort@mumc.nl.
authors.forename: Lucas J
authors.initials: LJ
authors.lastname: Poort
authors.affiliation: Department of Cranio-Maxillofacial Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Charlotte C
authors.initials: CC
authors.lastname: Kiewiet
authors.affiliation: Department of Pathology and CARIM School for Cardiovascular, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Jack P M
authors.initials: JP
authors.lastname: Cleutjens
authors.affiliation: Department of Radiation Oncology (Maastro Clinic) and GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Ruud
authors.initials: R
authors.lastname: Houben
authors.affiliation: Department of Radiation Oncology (Maastro Clinic) and GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Frank J P
authors.initials: FJ
authors.lastname: Hoebers
authors.affiliation: Department of Cranio-Maxillofacial Surgery and GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Peter A W H
authors.initials: PA
authors.lastname: Kessler
mesh_terms: D000818:Animals; D005147:Facial Bones / Q000601:surgery*; D005624:Frontal Bone / Q000601:surgery*; D016348:Osseointegration / Q000528:radiation effects*; D019736:Prostheses and Implants; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000379:methods; D060489:Prosthesis Retention; D011829:Radiation Dosage; D013552:Swine; D013556:Swine, Miniature
keywords: Bone-to-implant contact ratio; Craniofacial implants; Extraoral implants; Implant stability; Osseointegration