[Tissue reaction of the bone marrow to glass ceramic powder in the femurs of rats fed on a low-calcium diet].

Glass ceramic powder was injected into the bone marrow of 36 rats which were fed a low calcium (21 rats) or normal (15 rats) diet. They were sacrificed 7 or 8, 32 and 60 days after treatment. Histomorphometrical measurement revealed that the ratio of length of bone tissue which was in contact with glass ceramic mass to the circumference of each mass was larger in 32-day and 60-day groups than in the 7 or 8-day groups. Osteocyte-like cells were observed in the narrow space between ceramics and bone tissue in all specimens. Giant cells were seen in 1-2% of the glass ceramic surfaces in low calcium diet group and in 0.3% in normal diet group. No inflammatory reaction such as aggregation of lymphocytes nor leukocyte infiltration was observed in any specimens. Eighty-two percent of the surface of glass ceramic mass was covered with bone tissue 60 days after treatment in normal diet group.