[Relationship between gingival crevicular fluid and serum specific antibody titers in periodontitis and changes after the treatment].

Gingival crevicular fluid (GCF) samples were collected from 80 teeth in 20 periodontitis patients (13 RPP, 7 AP) before and 1 month, 7 months after treatment. Serum samples were taken at the same time. 12 healthy subjects (48 teeth) were chosen as the control group (H). The levels of IgG antibody to Bacteroides gingivalis was measured by ELISA. The relationship between serum and GCF specific antibodies was assessed. Before treatment, the mean ratio of antibody in GCF and serum (the GCF/Sr ratio) in both RPP and AP group was lower than 1, and significantly lower than that in H group. After treatment, the serum antibody titers greatly reduced while GCF antibody increased at 1 month after treatment and decreased at 7 months after treatment. The GCF/Sr ratio raised to greater than 1 in both RPP and AP. The elevation of GCF antibody may be associated with the lower antibody consumption caused by decreasing amount of B. gingivalis in pocket, and/or associated with the local antibody synthesis. It was suggested that the GCF/Sr ratio of antibody level might be used as a significant indicator in evaluation of treatment effectiveness.