METHODS: Thirty healthy subjects (including 15 smokers) were compared to periodontitis patients (n=30, including 15 smokers). Malondialdehyde (MDA) as a measure of lipid peroxidation and glutathione peroxidase (GSHPx) as a measure of antioxidant parameters were observed in saliva and blood. Further, the total antioxidant capacity (TOAC) was recorded in saliva. Samples were collected at baseline, 4, 12 and 24 weeks after non-surgical therapy.
RESULTS: Baseline data showed that the lowest level of lipid peroxidation was measured in saliva in the non-smoking periodontally-healthy subjects (0.065 ± 0.05 µmol/l). Smoking was seen to result in an increase of MDA (0.085 ± 0.08 µm) in this population (p>0.05). MDA levels were significantly higher in periodontitis patients who smoked (0.123 ± 0.08 µmol/l) compared to non-smoking healthy subjects (p<0.05). The periodontally-healthy subjects demonstrated significantly lower levels of GSHPX than the periodontally-diseased group. In contrast to the observed increases of MDA and GSHPX in the periodontitis subjects, antioxidant capacity (TOAC flow rate) was significantly reduced. Non-surgical periodontal treatment showed a positive effect on all investigated parameters. After a period of 6 months we recorded comparable results between the periodontitis group and controls.
CONCLUSION: Patients with periodontitis demonstrate more lipid peroxidation than healthy subjects in saliva. Imbalance between oxidative stress and antioxidant capacity may play a role in the pathogenesis of periodontal disease. Periodontal treatment has an effect of lipid peroxidation in saliva.