A biocompatible composition for tissue repair or regeneration in mammals comprising one or more glass former compounds selected from the group consisting of B2O3, P2O5, and SiO2 and director elements selected from the group consisting of Cu, Sr, Zn, Fe, Mn, Cr, V, Nb, Mo, W, Ba, Co, S, Al, Ti, Y, Mg, Si and/or Ni to promote in vivo calcium compound formation of calcium carbonate or other calcium compounds other than hydroxyapatite. Upon direct application of the biocompatible composition to a mammalian host, calcium carbonate or other calcium compounds other than hydroxyapatite form upon bioreaction of the composition with bodily fluids.