For controlling the ejection property and the clotting time of a composition comprising one or more bioresorbable ceramics, the use of carboxymethyl cellulose
Carboxymethylcellulose, notably sodium carboxymethylcellulose or other alkali metal or alkaline earth metal salts of carboxymethylcellulose, are employed to control solidification time of compositions comprising one or more bioresorbable ceramics, notably a hydratable calcium sulphate, in order to facilitate preparation of a ready-to-use composition for inserting into the body by injection.