we have developed two colonizable bone cements :the first is a partially resorbable bisphenol-a-glycidyl methacrylate (Bis-GMA)-based cement(PRC) and the second is a calcium phosphate cement (CPC).PRC is composed of aluminous silanized ceramic and particles of a bioresorbable polymer embedded in a matrix of Bis-GMA.CPC consisted of tricalcium phosphate, monocalcium phosphate monohydrate ,dicalcium phosphate dihydtrat ,and xanthane.Both cements were implanted into cavities drilled in rabbit femoral and tibital condyles .After 2,4 ,12,and 24 weeks of implantation ,histological observations and biomechanical tests were performed .With CPC, a progressive osteointegration with a concomitant biodegradation in the presence of macrophages were observed,The mechanical study revealed a decrease of the compressive strength unitil the 4th week,followed by a concomitant biodegradation in the elastic modulus with time .Moreover.by week 4, the histological study showed that the new bone was in direct contact with CPC margins .No inflammation was observed during the observation period. Strength was higher than that of cancellous bone and CPC(P<0.05) ar all observation periods.Its elastic modulus was greater than that of cancellous bone and CPC until the 4th week ,then fell under the values of the cancellous bone,(Bone 25:41s;1999)