[The evaluation of the adhesive properties of dental materials by using radioactive-labelled bacteria]

Dental materials with different surfaces were incubated with 111In-oxine-labelled bacteria Streptococcus mutans 20 min respectively 2 h, 6 h and 24 h. To determine the amount of the bacteria accumulated on the specimens we measured the radioactivity with a scintillation counter. The same measuring was done after decontamination by the help of ultrasonication. The comparison of activities shows that different dental material surfaces adhere different amounts of bacteria. The adhesive properties are material and time dependent, but the surface processing has a lower influence on the bacterial adherence. The lowest degree of bacterial adherence has the cobalt base alloy Gisadent KCM 83. On the other hand the highest remaining activity was found after decontamination of cobalt base alloy and PMMA resin Kallocryl A.