牙周治疗前后血清抗体滴度及亲和性的变化

目的 观察牙周治疗前后抗牙龈卟啉菌（Ｐｇ）抗体滴度及亲和性的变化，探讨其在牙周炎致病机制中的作用。方法 采用ＥＬＩＳＡ法，检测１７例牙周炎患者治疗前及治疗后１个月及６名健康对照者的血清抗Ｐｇ３８１ＩｇＧ抗体滴度及亲和性。结果 牙周炎组治疗前抗体滴度高于对照组（Ｐ〈０．００１），抗体滴度与探诊深度有负相关趋势，治疗后滴度显著降低（Ｐ〈０．０１）；亲和性与对照组间差异无显著性，治疗后也无显著性差异。

Titer and avidity of serum antibody to Porphyromonas gingivalis before and after periodontal therapy

OBJECTIVE: To observe the changes of titer and avidity of serum antibody to Porphyromonas gingivalis (Pg) before and one month after periodontal therapy, and to observe the correlation of titer and avidity of anti-Pg IgG with clinical indices. METHODS: ELISA and DEA-ELISA were used to determine the titer and avidity of serum IgG antibody to Pg381 before and one month after periodontal treatment in 17 periodontitis patients and 6 healthy control subjects. RESULTS: The titers of anti-Pg IgG antibody were higher in periodontitis patients than in healthy control subjects (P < 0.001). All patients were seropositive (titers to Pg were higher than 2-fold above the median for control subjects). IgG antibody avidity to Pg in periodontitis patients were not found to be significantly lower than that in control group. The titers to Pg decreased significantly at one month after periodontal therapy, but antibody avidity didn't change. Serum anti-Pg antibody titers had a tendency of negative correlation with probing depth. The antibody titers were significant higher in periodontitis patients with < or = 5 mm mean probing depth than in patients with > 5 mm mean probing depth. CONCLUSIONS: It is suggested that the humoral immune response to Pg381 is protective and this protective effect mainly depends on the titer of antibody.