Early dissolution of a morsellised impacted silicate-free bioactive glass in metaphyseal defects

The purpose of this study was to evaluate the biological properties of idealized, morsellised impacted Corglaes, a soluble silicate-free glass. Twenty-two sheep underwent implantation of pellets in six metaphyseal defects in both rear limbs. Particle size distribution of all aggregates (except the autograft) approached the ideal logarithmic grading line and all implants were impacted to a standard compactive effort. Treatment groups consisted of (1) empty defect (negative control), (2) autograft (positive control), (3) allograft (clinical control), (4) allograft idealized with Corglaes, (5) 50/50 allograft/Corglaes and (6) Corglaes. Defects were sealed with polymethylmethacrylate. Healing of the defects was evaluated at 7 weeks (n=6) and 14 weeks (n=16) with computed tomography, histology, and histomorphometry. Remnants of Corglaes were found within one of the defects 7 weeks after implantation. Defects filled with mixtures containing 50% or 100% Corglaes were less dense, contained less bone and more fibrous tissue than defects with allograft, autograft, or allograft idealized with Corglaes. Allograft idealized with Corglaes may be considered for impaction grafting in revision hip arthroplasty, as well as local delivery of antibiotics. However, further studies and potential revision of the agent are required before mixtures containing concentrations of Corglaes equal to or higher than 50% can be recommended.