The influence of several sinter additives (three glasses, magnesium acetate, bismuth trioxide) on the compressive strength and also on the solubility of a sintered ceramics, which is composed of 57.6Mol% CaO, 26.2Mol% P2O5, 10.4Mol% ZrO2 and 5.8Mol% CaF2 was tested. The amount of sinter additives, pre-mixing of the powders, pressure power, sintering temperature and sintering time were varied. The most dense samples were produced with the finest powders (D50 ~ 1/m) and the highest sintering temperatures (1200°C). The mechanical stability of the samples was more influenced by the particle size of the powders than by the kind of binder as well as the pressure power. The compressive strength of the sintered samples ranged between 180MPa (D50 of the powder = 2.4/m) and 530MPa (D50 of the powder < 1/m). Storing of the samples in simulated body fluid for 4 weeks at a temperature of 37°C did not influence the compressive strength significantly. The sintered ceramics can be finished, for instance by grinding or polishing.