SUMMARY

Neutrophils (polymorphonuclear leucocytes ) are the principal cells of the host defense system. Consequently, if periodontal pathogen – derived substances in the gingival crevice signifi-cantly inhibit their function, they could shift the bacterial – host balance in favour of the bacteria. The aim of investigation was to determine if the ammonium ions (periodontal pathogens produce substantial amounts) affects the main neutrofils oxidative function – reactive oxygen species generation measured by luminol and lucigene – dependent chemiluminescence. Our results show that ammonium ions both in the group of non-periodontally diseased persons and in periodontitis patients have significant inhibitive effect on luminol- and lucigene-dependent chemiluminescence, which de