Prognosis of periodontitis recurrence after intensive periodontal treatment using examination of serum IgG antibody titer against periodontal bacteria

Chronic periodontitis is associated with systemic diseases such as atherosclerosis. In this study, we evaluated the efficacy of serum IgG antibody titer to periodontal bacteria for prognosis of periodontitis recurrence during supportive periodontal therapy (SPT) phase. The 139 patients during SPT phase were selected and divided to two groups as follows: "Stable" and "Recurrence" group at SPT phase for case-control study: "High IgG titer" and "Normal IgG titer" group before transition to SPT phase for cohort study. We examined whether clinical findings or serum IgG antibody titers to periodontal bacteria are risk factors for the development of periodontitis recurrence. Case-control study showed thatthere were significant differences between the stable and recurrence groups in age and number of teeth. The serum IgG antibody titer to Eikenella corrodens FDC1073, Porphyromonas gingivalis SU63, and Campylobacter rectus ATCC33238 was significantly higher in the recurrence group. Next, we found, that the recurrence ratio in the high IgG titer group to Gram-negative obligate anaerobe, Prevotella intermedia, Treponema denticola, and C. rectus was significantly higher than that of the normal IgG titer group. Taken together, serum IgG antibody titer test is useful in the prognosis of periodontitis recurrence during the SPT phase.