Summary: Introduction: Thiobarbituric acid reacting substances (TBARS) are products of lipoperoxidation. Lipoperoxidation damages various tissues by reactive oxygen intermediates (ROI) and thus TBARS are generally considered as markers of oxidation stress and lipid impairment. Aim. The aim of this project was to find possible nexus between chosen characteristics of immune system, parodont status and TBARS concentrations in saliva in healthy volunteers. In addition, we tried to find the origin of TBARS in saliva in patients with parodontopathies, where we focused on entire or partially plasmatic TBARS passage to saliva hypothesis. Subjects & Methods. Our volunteers consisted of 31 young healthy men and 29 young healthy women with an average age of 21.5 ± 1.4 yr (Study A) and 15 patients in age interval of 20–60 yr (Study B). Parodont status was examined using PBI (Papillary-Bleeding-Index). TBARS were determined, in plasma and saliva, spectrofluorometrically (λex = 515 nm, λem = 553 nm). Testosterone (TST) levels were measured using radioimmunoassay. Immunoglobulines and other haematological parametres were determined turbidimetrically. Results. Study A. The women with higher PBI levels had shown higher concentrations of TST (p<0.03) in comparison to women with lower PBI. In men,we observed positive dependance between PBI and TST (statistically not significant). The levels of salivary TBARS positively correlated with the levels of salivary TST in women (p<0.02) and negatively correlated with the levels of salivary TST in men (statistically not significant). When comparing the average levels of TST to neutrophiles and lymphocytes, we observed that when there are higher TST levels then IgM levels (p<0.01) and neutrophile number (p<0.02) are decreased, whereas lymphocyte number is increased (p<0.03). Study B. There hadn’t been found any statistical significance in the relation between plasmatic and salivary TBARS levels (Pearson coefficient 0,17; p<0,52). Comparing TBARS plasmatic levels between Parodontopathies and Control group, there hadn’t been found any statistically significant difference. However, when comparing TBARS salivary levels between Parodonthopathies and Control group, there has been found group mean value difference (p<0,04). Conclusion. To conclude we can say, that the relation between salivary TBARS levels an oral cavity soft tissue status remains unclear yet. From clinical view, however, the results showing on local and not plasmatic levels of salivary TBARS, could be of great importance in clinical study, potentially allowing diagnosis or parodonthopathies pathogenesis understanding. In future, there are clinical studies concerning causality, mainly microbiological effect on salivary TBARS levels, needed.

        Key words: TBARS – malondialdehyde – salivary testosterone – PBI – parodontopathies – oxidation stress