title: In vivo evaluation of resorbable bone graft substitutes in a rabbit tibial defect model.
abstract: Calcium sulfate as a bone graft substitute is rapidly resorbed in vivo releasing calcium ions but fails to provide long-term three-dimensional framework to support osteoconduction. The setting properties of calcium sulfate however allow it to be applied in a slurry form making it easier to handle and apply in different situations. This study examines the in vivo response of calcium sulfate alone and as a carrier for a coralline hydroxyapatite in an established bilateral corticocancellous defect model in rabbits. Defects were filled flush to the anterior cortex with a resorbable porous ceramic alone and in combination with calcium sulfate slurry, calcium sulfate slurry alone or calcium sulfate pellets and examined at time points up to 52 weeks. Specimens where assessed using Faxitron X-ray, light and electron microscopy. Calcium sulfate in either slurry or pellet form does indeed support new bone formation alone however, complete filling of the bone defect is not observed. Calcium sulfate in slurry form does however improve the surgical handling of particulate bone graft substitutes such as Pro Osteon 200 R, which remained as an osteoconductive scaffold for up to 52 weeks and may have played an important role in the ultimate closure of the cortical windows.
authors.affiliation: Orthopaedic Research Laboratories, University of New South Wales, Division of Surgery, Prince of Wales Hospital, Sydney, High Street, Randwick, NSW 2031, Australia.
authors.forename: D
authors.initials: D
authors.lastname: Stubbs
authors.forename: M
authors.initials: M
authors.lastname: Deakin
authors.forename: P
authors.initials: P
authors.lastname: Chapman-Sheath
authors.forename: W
authors.initials: W
authors.lastname: Bruce
authors.forename: J
authors.initials: J
authors.lastname: Debes
authors.forename: R M
authors.initials: RM
authors.lastname: Gillies
authors.forename: W R
authors.initials: WR
authors.lastname: Walsh
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials; D018786:Bone Substitutes / Q000737:chemistry*; D001842:Bone and Bones / Q000737:chemistry; D002118:Calcium / Q000737:chemistry; D002133:Calcium Sulfate / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D017886:Durapatite; D004577:Electron Probe Microanalysis; D006882:Hydroxyapatites / Q000737:chemistry*; D007477:Ions; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D016377:Organ Transplantation; D019736:Prostheses and Implants; D011817:Rabbits; D013977:Tibia / Q000473:pathology*; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D006882:Hydroxyapatites; D007477:Ions; C119955:coralline hydroxyapatite; D017886:Durapatite; D002118:Calcium; D002133:Calcium Sulfate