THE INFLUENCE OF SINTERING TEMPERATURE ON THE PROLIFERATION OF FIBROBLASTIC CELLS IN CONTACT WITH HA-BIOCERAMICS

HA-ceramics used in human surgery as osteoconductive surfaces show a g reat variety of characteristics. Certain characteristics such as grain size, porosity, and surface area, are controlled by the sintering tem perature of the slurry. We grew L-929 fibroblast cells on HA-ceramic d isks that had been sintered at different temperatures ranging from 850 degrees-1350 degrees C. The cell line growth rate was lower on cerami c disks than on the culture-grade polystyrene used as a negative contr ol. Cell growth correlated with the ceramic sintering temperature alth ough no significant difference in the cell adhesion to the different c eramics was shown. Growth rate on ceramics sintered at low temperature s (850 degrees and 950 degrees C) was negative whereas it was positive on disks sintered at higher temperatures. When the cells were separat ed from the disks by a polycarbonate membrane, the growth rate was neg ative on those membranes in contact with low-temperature sintered disk s and positive on the high-temperature sintered disks. The calcium and phosphorus concentration in the culture medium in contact with cerami cs sintered below 1050 degrees C decreased during the culture period. Ceramics sintered between 1100 degrees and 1250 degrees C brought abou t an increase in Ca and P concentrations while ceramics sintered at hi gher temperatures did not induce any changes. SEM examination of the 8 50 degrees and 1200 degrees C sintered ceramics showed that the 850 de grees C sintered ceramics consisted of small grains with pores between them and the 1200 degrees C sintered ceramics were made of larger gra ins without any visible pores, thereby decreasing the surface of mater ial in contact with the culture medium. This difference in surface are a was confirmed by the fact that the amount of albumin adsorbed onto t he ceramic was dependent on the sintering temperature. In conclusion, the modification of the culture medium brought about by high-surfaced ceramics could influence the growth of cells with which such ceramics come in contact. (C) 1997 John Wiley & Sons, Inc.