Relationship between prostaglandin e₂ concentrations in periapical exudates from root canals and clinical findings of periapical periodontitis

In this study the relationship of prostaglandin E₂ (PGE₂) concentrations in periapical exudates with clinical findings of teeth with periapical periodontitis is discussed. Periapical exudate samples were obtained from root canals of 77 endodontically involved teeth during routine root canal treatment by the quantitative sampling method using paper points. PGE₂ concentrations in periapical exudates (PE-PGE₂) were determined by radioimmunoassay. Significantly higher levels of PGE₂ were found in periapical exudates from teeth with radiolucent areas than from teeth without radiolucent areas (236.8 ± 521.3 pg/μl vs. 14.9 ± 23.1 pg/μl, respectively). The elevated PE-PGE₂ levels were associated with the presence of clinical symptoms that reflected an acute inflammation in the periapical lesion. In contrast, a significantly negative association of decreased PE-PGE₂ levels with increasing size of radiolucent areas was demonstrated. These results suggested that PGE₂ was produced locally in periapical lesions and that the PGE₂ concentration in periapical exudate could reflect the state of the disease activity in periapical periodontitis.