The uniqueness of periodontal diseases is caused by several factors. This group of diseases is caused by numerous bacterial species formed in the dental biofilm, and one cannot distinguish the specific pathogen that is responsible for the disease initiation or progress (though Gram-negative anaerobic rods are associated with the advanced form of the disease). The disease is both infectious and inflammatory in its nature, and in the state of health there is always a subclinical level of inflammatory response, caused by the so-called harmless bacteria. Negligence in oral hygiene may result in maturation of the biofilm and trigger host response, manifesting clinically as gingivitis or-later and in susceptible subjects-as periodontitis. The article presents the contemporary knowledge of the inflammatory reaction occurring in tissues surrounding the tooth during periodontal inflammation. The most important mechanisms are described, together with implications for clinicists.
Keywords: Inflammation; Mediators of inflammation; Non-specific immunity; Periodontal diseases.