title: The efficacy of Biobon and Ostim within metaphyseal defects using the Göttinger Minipig.
abstract: BACKGROUND
  To compare bio, osteocompatibility, rate of resorption and remodeling dynamics of two clinically used bone substitutes.
  
  
  METHODS
  In a randomized fashion Biobon and Ostim were implanted bilaterally into the proximal metaphyseal tibiae of 18 Göttinger Minipigs in a direct right versus left "intra-individual" comparison. Fluorescent labelling was used. Microradiographic, histological and morphometric evaluation was carried out at 6, 12 and 52 weeks.
  
  
  RESULTS
  Both bone substitutes showed good biocompatibility, bioactivity and osteoconductivity. The degradation dynamics of both materials differed. Degradation of Ostim stopped after 6 weeks postoperatively, whereas Biobon was degraded slowly but evenly over the time intervals. Only at 6 weeks a significant (P < 0.05) difference in resorption rate was detected. Both Biobon and Ostim showed incomplete resorption after a year.
  
  
  CONCLUSIONS
  After 1 year no "restitutio ad integrum" could be observed in either group. Similar to ceramics, a thorough osseous incorporation seemed to inhibit further degradation of both bone substitute materials.
authors.affiliation: Klinik für Orthopädie und Unfallchirurgie, Universitätsklinikum Aachen, Pauwelsstr. 30, 52074, Aachen, Germany. christianspies1@gmx.net
authors.forename: Christian K G
authors.initials: CK
authors.lastname: Spies
authors.forename: Stefan
authors.initials: S
authors.lastname: Schnürer
authors.forename: Tobias
authors.initials: T
authors.lastname: Gotterbarm
authors.forename: Steffen
authors.initials: S
authors.lastname: Breusch
mesh_terms: D000818:Animals; D018786:Bone Substitutes; D008422:Materials Testing; D016348:Osseointegration; D013552:Swine; D013556:Swine, Miniature
chemical_list: D018786:Bone Substitutes