title: In vivo evaluation of biofunctionalized implant surfaces with a synthetic peptide (P-15) and its impact on osseointegration. A preclinical animal study.
abstract: OBJECTIVE
  The overall aim of the study was to investigate a biofunctionalized implant surface with electrochemically deposition of hydroxyapatite and the synthetic peptide (P-15) and its effect on osseointegration.
  
  
  METHODS
  Three modified implant types of ANKYLOS®C/X implants were used; (1) machined implants used as negative control (M, n = 20), (2) implants with the FRIADENT®plus surface (grit blasted and acid-etched) used as positive control (P, n = 20), and (3) implants with a biomimetic surface consisting of hydroxyapatite and the synthetic 15 aminoacids containing peptide P-15 (BP, n = 40). The implants were randomly inserted in the mandibles of 10 beagle dogs following 4 months after tooth extraction (P1-P4). Three animals were sacrificed 2 and 7 days after implant insertion, respectively, and four animals were sacrificed 6 months post implant insertion. Bone-to-implant contacts (BICs) were analyzed via histomorphometrical analyses at five different region of interests (ROIs); two at the middle part on either side of the implant (ROI 1/4), two at the apical part of the implant at each side (ROI 2/3), and one at the tip of the implant (ROI 5).
  
  
  RESULTS
  All implant surfaces showed a high level of osseointegration and osteoconductivity. The cumulative implant survival rate (CSR) was 93.8%, 100% in the M, 85% in the P, and 95% in the BP group. No statistical difference in BICs at ROI 1/4, 2/3, and 5 could be shown between implant types following 2 and 7 days of healing. BIC values increased in all groups over time. After 6 months of healing the BP group showed superiority in BIC in ROI 2/3 (73.2 ± 15.6%) compared to the P (48.3 ± 10.6%) and M group (66.3 ± 30.2%) with a significant difference between BP and P (P = 0.002).
  
  
  CONCLUSIONS
  It is hypothesized, that the surface biofunctionalization improves peri-implant bone formation and remodeling, leading to an increased bone-to implant contact. However, within the limitations of the study set-up no benefit in the early phase of osseointegration could be established for dental implants with P-15 containing surface in this study.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen, Germany. Christian.Schmitt@uk-erlangen.de.
authors.forename: Christian M
authors.initials: CM
authors.lastname: Schmitt
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Koepple
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Tobias
authors.identifier: http://orcid.org/0000-0002-3763-3122
authors.initials: T
authors.lastname: Moest
authors.affiliation: Institute of Medical Biometrics and Clinical Epidemiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Konrad
authors.initials: K
authors.lastname: Neumann
authors.affiliation: DENTSPLY Implants, Mannheim, Germany.
authors.forename: Tamara
authors.initials: T
authors.lastname: Weisel
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Karl Andreas
authors.initials: KA
authors.lastname: Schlegel
mesh_terms: D000818:Animals; D018786:Bone Substitutes / Q000494:pharmacology*; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004285:Dogs; D004311:Double-Blind Method; D020007:Implants, Experimental; D008334:Mandible / Q000601:surgery; D016348:Osseointegration; D010446:Peptide Fragments / Q000494:pharmacology*; D011446:Prospective Studies; D013499:Surface Properties; D013524:Surgical Flaps
chemical_list: D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D010446:Peptide Fragments
keywords: Osseointegration; P-15; biofunctionalization; biomimetic; bone healing; bone regeneration; bone-to-implant contact; dental implant; histology; implant surface