The Journal of Bone and Joint Surgery, Vol 74, Issue 10 1456-1463, Copyright © 1992 by Journal of Bone and Joint Surgery, Inc
The effect of a composite of polyorthoester and demineralized bone on the healing of large segmental defects of the radius in rats
E Solheim, EM Pinholt, R Andersen, G Bang and E Sudmann
Institute for Surgical Research, Rikshospitalet, University of Oslo, Norway.
The effect of a composite of demineralized bone mixed with polyorthoester
on the healing of large segmental defects in the rat radius was studied.
Sixty male Wistar rats were divided into four groups, A through D, and an
osteoperiosteal diaphyseal defect of 50 per cent of the length of the bone
was made in the right radius of each rat. In Group A, the defect was filled
with polyorthoester and demineralized bone; in Group B, demineralized bone;
and in Group C, polyorthoester. No material was implanted in the defects in
the Group-D rats. The rats were killed fifty days postoperatively. The
formation of bone in the defects was quantified with computer-assisted
measurements of the area on radiographs. The host-tissue response was
evaluated with light microscopy. Defects that had been filled with the
composite of polyorthoester and demineralized bone or with demineralized
bone alone showed regeneration of bone corresponding to 93.6 and 77.6 per
cent of the area of the defect, respectively. Defects that had no implant
or that had been filled with polyorthoester alone showed significantly less
formation of bone. No inflammation was seen with light microscopy, and only
traces of the polyorthoester could be detected in the defects that had been
filled with the composite or with polyorthoester alone.