title: Bone response to a novel highly porous surface in a canine implantable chamber.
abstract: Long-term survival of uncemented hip components is dependent upon successful biological fixation. This study examined a new prosthetic surface treatment consisting of a highly porous open structure of commercially pure titanium, Tritanium Dimensionalized Metal; its overall porosity is approximately 65-70%. With the use of an implantable chamber in dogs, the effects of this treatment on bone ingrowth and strength of attachment were compared to both titanium (overall porosity of 30-35%) and cobalt chrome beads (overall porosity of 35-40%), with and without hydroxyapatite coating. At 6 and 12 weeks, chambers were explanted and specimens underwent high-resolution radiographic imaging and mechanical testing. At 12 weeks, Tritanium surfaces had greater bone penetration and tensile strength than remaining surface types. Over 40% of the Tritanium specimens had a tensile strength greater than 500 N, exceeding the testing capability of the servohydraulic equipment. The highly porous Tritanium surfaces allow for a far greater amount of bone ingrowth than beaded surfaces, and may create a geometry that enhances mechanical strength. Tritanium Dimensionalized Metal surface treatment may result in a clinically valuable implant fixation surface to induce rapid ingrowth and a strong bone-implant interface, contributing to increased implant survivorship.
authors.affiliation: Musculoskeletal Research Center, New York University Hospital for Joint Diseases, 301 East 17th Street, New York, NY 10003, USA. sallyfrenkel@yahoo.com
authors.forename: Sally R
authors.initials: SR
authors.lastname: Frenkel
authors.forename: William L
authors.initials: WL
authors.lastname: Jaffe
authors.forename: Fred
authors.initials: F
authors.lastname: Dimaano
authors.forename: Kazuho
authors.initials: K
authors.lastname: Iesaka
authors.forename: Tian
authors.initials: T
authors.lastname: Hua
mesh_terms: D000497:Alloys; D000818:Animals; D001846:Bone Development / Q000502:physiology*; D002857:Chromium; D020099:Coated Materials, Biocompatible; D003035:Cobalt; D015194:Diffusion Chambers, Culture; D004285:Dogs; D017886:Durapatite; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology; D020007:Implants, Experimental; D008855:Microscopy, Electron, Scanning; D016062:Porosity; D011859:Radiography; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium
chemical_list: D000497:Alloys; D020099:Coated Materials, Biocompatible; D002857:Chromium; D003035:Cobalt; D017886:Durapatite; D014025:Titanium