History of engineering & technology Technology: general issues amorphous calcium carbonate apatite bioactivity bioceramics biocompatibility biodegradable biomaterial biphasic calcium phosphate nanoparticle (BCP-NP) bone implants bone regeneration bone substitute calcium orthophosphates corrosion analysis cuttlefish bone eggshell gelatin methacryloyl (GelMA) global DNA methylation human tooth powder hydrogel hydroxyapatite inorganic nanomaterials magnesium and its alloys mechanobiology metallic nanomaterials microgeometry microstructure microwave-assisted hydrothermal synthesis mussel shell