[Dynamics of antibiotic release from glass ceramic material.]

Using the agar pit method, the authors assessed elution curves of the antibiotics lincomycin, gentamicin and neomycin previously used to saturate bioactive glass ceramic materials BAS-0 and BAS-HA with different porosities. The release into buffered saline at a temperature of 37 C was investigated for a 60-day period. Coagulated human blood on the surface of the granules and blocks used retarded and prolonged the release of antibiotics from glass ceramics. Elution took place in two stages: during the first 12 hours, the maximum of each antibiotic was released and this rapid rise was followed by flattening of the curve and release of a small amount of antibiotic only, which however was detectable still after 60 days. From BAS-0 lincomycin was released most readily, from BAS-HA gentamicin. The poorest release was recorded in all instances from neomycin, al-though the amount of this antibiotic was sufficient for bactericide activity. Further research should lead to prolongation of the first stage of maximum antibiotic release. Key words: bioactive, porous glass ceramics, release of antibiotics from carrier.