Abstract:

Objective：To analyze the serum IgG titers to Aggregatibacter actinomycetemcomitans(Aa) and associated factors in patients with aggressive periodontitis (AgP).Methods:Venous blood samples were collected from 62 AgP patients and 45 periodontal healthy controls, unstimulated whole saliva and pooled subgingival plaque samples of AgP patients were also collected for the detection of Aa (PCR method). Serum IgG titers to Aa serotype c were measured by enzyme-linked immunosorbnent assay (ELISA).Results:The detection rates of serum IgG to Aa serotype c in the AgP patients and the healthy controls were both 100%. The AgP patients exhibited significantly higher IgG titers to Aa serotype c than the healthy controls (11.1±1.9 vs. 9.1±1.8, P<0.01). There was no significant difference in serum IgG levels to Aa serotype c and in the prevalence of high-responding patients to Aa serotype c between the incisor-first molar type AgP patients and generalized AgP patients. Serum IgG titers to Aa serotype c in the Aa-positive AgP patients (the patients who were Aa-positive in subgingival plaque or saliva) were significantly higher than those of the Aa-negative patients (11.9±1.3 vs. 10.7±2.1, P<0.05). Conclusion:Serotype c was the main serotype of Aa in Chinese patients with AgP. Serum IgG responses in generalized AgP patients were comparable to those in incisor-first molar type AgP patients.

Key words: Aggressive periodontitis, Aggregatibacter actinomycetemcomitans, Serogroup, Immunoglobulin G