The combined additions of Ca2+ and PO43- to the SiO2-ZrO2 system were attempted through in situ sol-gel technique. Six different combinations were synthesized and the results were compared with pure SiO2-ZrO2 system. The synthesized materials were subjected to accelerated leaching tests to evaluate their phase degradation behavior, nanoindentation for mechanical analysis, and immersion tests in simulated body fluids (SBF) to test their apatite forming ability. The results confirmed the phase stability of t-ZrO2 till 1100 degrees C and the presence of SiO2, Ca2+, and PO43- in t-ZrO2 matrix exhibited good apatite forming ability during SBF immersion and their reluctance in phase degradation during accelerated leaching tests. However, the values of hardness and Young's modulus were found inferior in comparison with the commercial t-ZrO2 products.