Compositions useful for repairing osseous defects include particulate bioactive and biocompatible glass including 40 to 58% by weight silica, 10 to 320 by weight calcia, 10 to 320 by weight soda and 2 to 10% by weight phosphorus pentoxide. The particles have a size distribution of: 20 to 65% by weight, 50 microns to less than 297 microns; 20 to 45% by weight, 297 to less than 350 microns; and 15 to 40% by weight, 350 microns to less than 420 microns. Methods for repairing osseous defects utilizing such compositions are also provided.