Bioceramic inlays do not improve mechanical incorporation of grit-blasted titanium stems in the proximal sheep femur

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Keranen P, Koort J, Itala A, Ylanen H, Dalstra M, Hupa M, Kommonen B, Aro HT
Publisher: WILEY-LISS
Publication year: 2010
Journal: Journal of Biomedical Materials Research Part A
Journal acronym: J BIOMED MATER RES A
Volume number: 92A
Issue number: 4
Start page: 1578
End page: 1586
Number of pages: 9
ISSN: 1549-3296


Abstract

The aim of the present study was to determine, if bioactive glass (BG) surface inlays improve osseointegration of titanium implants in the proximal femur of adult sheep. In simulation of uncemented primary stems (nine animals), only the proximal part of the implants was grit-blasted and three surface slots of the grit-blasted region were filled with sintered BG microspheres. Primary stems were implanted using press-fit technique. In revision stem simulation (eight animals), grit-blasting was extended over the whole implant and seven perforating holes of the stem were filled by sintered BG granules. Revision stems were implanted with a mixture of autogenous bone graft and BG granules. Comparison with solid partially or fully grit-blasted control stems implanted in the contralateral femurs was performed in the primary and revision stem experiments at 12 and 25 weeks, respectively. Implant incorporation was evaluated by torsional failure testing and histomorphometry. Only one-third of the primary stems anchored mechanically to bone. The revision stems incorporated better and the BG inlays of the revision stems showed ingrowth of new bone. However, there were no significant differences in the torsional failure loads between the stems with BG inlays and the control stems. In conclusion, surface BG inlays gave no measurable advantage in mechanical incorporation of grit-blasted titanium implants. Overall, the proximal sheep femur, characterized by minimal amount of cancellous bone and the presence of adipocytic bone marrow, seemed to present compromised bone healing conditions.


Keywords

bone graft substitute, femur, sheep, titanium implant

Last updated on 2019-19-11 at 01:53