Abstract: Methods of mixing delivering biocompatible cement, paste, putty, or gel for bone and cartilage repair are described in this invention. Powder-like solid materials are loaded into a first syringe. Liquids are loaded into one or multiple syringes. The liquids are injected into the first syringe containing the solid materials. To force the liquids through the solid, prevent bubble formation and provide intimate intermixing, the liquids are injected in the very proximity of the plunger end of the syringe containing the solid materials. The first syringe is preferably held vertical with the tip facing up so as to avoid bubble formation that in turn could cause back-pressure build-up and plug the first syringe during injection. The described methods of mixing the liquids with the solids allows to form a rheological paste, cement, putty, or gel in the first syringe.