Do salivary and serum collagenases have a role in an association between obstructive sleep apnea syndrome and periodontal disease? A preliminary case-control study.

OBJECTIVES: Despite increasing evidence for an association of obstructive sleep apnea syndrome (OSAS) and periodontal disease, the pathophysiological linking mechanisms remain unclear. This study aims to evaluate the salivary and serum matrix metalloproteinase-2, -8, -9 (MMP-2, -8, -9), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), myeloperoxidase (MPO), neutrophil elastase (NE), neutrophil gelatinase-associated lipocalin (NGAL), as well as degree of activation of MMP-2, -9 of patients with and without OSAS. DESIGN: A total of 50 individuals were included in the study. There were 13, 17 and 20 individuals, respectively in the control (non-OSAS) group, mild-to-moderate OSAS and severe OSAS groups. Saliva, serum samples and clinical periodontal parameters were collected. Biofluid samples were analysed by immunofluorometric assay (IFMA), enzyme-linked immunosorbent assay (ELISA), western immunoblotting and gelatine zymography. Statistical analyses were performed using D'Agostino-Pearson omnibus normality test, Kruskal-Wallis test and Spearman rho rank correlation analysis. RESULTS: There were no statistically significant differences in clinical periodontal parameters between the study groups. Salivary NE and proMMP-2 levels were significantly lower in the OSAS groups than the control group (p<0.05). Serum proMMP-9 concentration and the degree of MMP-9 activation in saliva were significantly lower in the severe OSAS group than the control group (p<0.05). There were significant correlations between salivary and serum proMMP-9 and -2 concentrations (p<0.05). Serum proMMP-2, NE and salivary proMMP-9 and -2 negatively correlated with indicators of OSAS severity (p<0.05). CONCLUSIONS: The present findings do not support a pathophysiological link between the severity of OSAS and clinical periodontal status via neutrophil enzymes or MMPs.

Salivary cytokines and the association between obstructive sleep apnea syndrome and periodontal disease.

BACKGROUND: A higher prevalence of periodontal disease has been reported in patients with obstructive sleep apnea syndrome (OSAS), and these two chronic conditions may be linked via inflammatory pathways. The aim of the present study is to evaluate the salivary interleukin (IL)-1ß, IL-6, IL-21, IL-33, and pentraxin-3 (PTX3) concentrations in patients with and without OSAS. METHODS: A total of 52 patients were included in the study. Thirteen individuals were in the control (non-OSAS) group, 17 were in the mild/moderate OSAS group, and 22 were in the severe OSAS group. Clinical periodontal measurements were recorded, and saliva samples were obtained before initiation of periodontal intervention. Enzyme-linked immunosorbent assay was used to determine salivary cytokine concentrations. Data were statistically analyzed using D'Agostino-Pearson omnibus normality, Spearman ρ rank, Kruskal-Wallis, and Dunn tests. RESULTS: Salivary IL-6 and IL-33 concentrations were similar in the two OSAS groups (P >0.05), which were statistically higher than the control group (P <0.05). IL-1ß, IL-21, and PTX3 concentrations were similar in the study groups. The only significant correlation between clinical periodontal parameters and salivary cytokines was found between clinical attachment level (CAL) and IL-21 (P = 0.02). Highly significant correlations were found between probing depth, CAL measures, and indicators of OSAS severity (P <0.01). CONCLUSIONS: The present findings suggest that OSAS may have an increasing effect on salivary IL-6 and IL-33 concentrations regardless of OSAS severity. Additional investigation is required to elucidate a potential bidirectional relationship between OSAS and periodontal disease.