Comparison of serum amyloid A protein and C-reactive protein levels as inflammatory markers in periodontitis

PURPOSE: The purpose of this study was to compare serum amyloid A (SAA) protein levels with high-sensitive C-reactive protein (hs-CRP) levels as markers of systemic inflammation in patients with chronic periodontitis. The association of serum titers of antibodies to periodontal microbiota and SAA/hs-CRP levels in periodontitis patients was also studied. METHODS: A total of 110 individuals were included in this study. Patients were assessed for levels of hs-CRP and SAA. Nonfasting blood samples were collected from participants at the time of clinical examination. The diagnosis of adipose tissue disorders was made according to previously defined criteria. To determine SAA levels, a sandwich enzyme-linked immunosorbent assay was utilized. Paper points were transferred to a sterile tube to obtain a pool of samples for polymerase chain reaction processing and the identification of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Tannerella forsythia. The serum level of IgG1 and IgG2 antibodies to P. gingivalis, A. actinomycetemcomitans, and T. forsythia was also determined. RESULTS: SAA and hs-CRP levels were higher in periodontitis patients than in controls (P3 mg/L) and SAA (>10 mg/L) were significantly associated with chronic periodontitis (P=0.004). The Spearman correlation analysis between acute-phase proteins showed that SAA positively correlated with hs-CRP (r=0.218, P=0.02). In the adjusted model, chronic periodontitis was associated with high levels of SAA (odds ratio [OR], 5.5; 95% confidence interval [CI], 1.6-18.2; P=0.005) and elevated hs-CRP levels (OR, 6.1, 95% CI, 1.6-23.6; P=0.008). Increased levels of serum IgG2 antibodies to P. gingivalis were associated with high levels of SAA (OR, 3.6; 95% CI, 1.4-8.5; P=0.005) and high concentrations of hs-CRP (OR, 4.3; 95% CI, 1.9-9.8; P<0.001). CONCLUSIONS: SAA and hs-CRP concentrations in patients with chronic periodontitis are comparably elevated. High serum titers of antibodies to P. gingivalis and the presence of periodontal disease are independently related to high SAA and hs-CRP levels.

Association between immunoglobulin G1 against Tannerella forsythia and reduction in the loss of attachment tissue

PURPOSE: To evaluate whether the levels of immunoglobulin G (IgG) antibody to Tanerella forsythia are associated with periodontal status. METHODS: Patients with a diagnosis of chronic periodontitis were considered candidates for the study; thus 80 chronic periodontitis patients and 28 healthy persons (control group) were invited to participate in this investigation. The presence of T. forsythia was detected by polymerase chain reaction (PCR) analysis using primers designed to target the respective 16S rRNA gene sequences. Peripheral blood was collected from each subject to identify the IgG1 and IgG2 serum antibodies against T. forsythia. All microbiological and immunological laboratory processes were completed blindly, without awareness of the clinical status of the study patients or of the periodontal sites tested. RESULTS: The bivariate analysis showed that lower mean levels of clinical attachment level (CAL) and probing depth were found in the presence of the IgG1 antibody titers against whole-cell T. forsythia; however, only the difference in CAL was statistically significant. In the presence of the IgG2 antibody titers against whole-cell T. forsythia, the periodontal parameters evaluated were higher but they did not show statistical differences, except for plaque. The unadjusted linear regression model showed that the IgG1 antibody against whole-cell T. forsythia in periodontitis patients was associated with a lower mean CAL (beta=-0.654; 95% confidence interval [CI], -1.27 to -0.28; P<0.05). This statistically significant association remained after adjusting for possible confounders (beta=-0.655; 95% CI, -1.28 to -0.29; P<0.05). On the other hand, smoking was a statistically significant risk factor in the model (beta=0.704; 95% CI, 0.24 to 1.38; P<0.05). CONCLUSIONS: Significantly lower mean levels of CAL were shown in the presence of the IgG1 antibody titers against whole-cell T. forsythia in periodontitis patients. Thus, the results of this study suggest that IgG1 antibody to T. forsythia may have been a protective factor from periodontitis in this sample.