Methods for improving the antibacterial, osteoconductive, and/or osteoinductive characteristics of silicon nitride and/or other ceramic materials, particularly to make them more suitable for use in manufacturing biomedical implants. In some embodiments and implementations, the surface chemistry and/or morphology of a silicon nitride bioceramic may be modulated significantly through thermal, chemical, and/or mechanical treatments to achieve such advantageous results. A portion of the resulting material, such as a glaze or upper layer of the material, may be separately produced as a powder or frit, for example, and used in manufacturing biomedical implants and/or other products, such as by using such portion of the material as a coating or filler. In other embodiments the surface material may be separately manufactured as a silicon oxynitride monolith.
