Host mediators in endodontic exudates. II. Changes in concentration with sequential sampling.

Exudate is often found in the root canal of teeth requiring endodontic therapy. The aim of this study was to evaluate the relationship of sequential changes of different host mediators in endodontic exudates to clinical and radiographic findings. Thirty-two nonvital teeth with periapical symptoms were evaluated. Exudates were collected with filter paper strips every 3 min after opening of the pulp chamber. The concentrations of beta-glucuronidase, IgG, IgA, IgM, and interleukin-1 beta in the exudates were analyzed. In general, the concentration of the mediators in exudates from less involved lesions did not change over time. The exception was an increase in the IgM concentration when patients presented with percussion or palpation sensitivity. In contrast, in the more involved lesions, the concentrations of IgA and IgM increased as sampling progressed. The concentrations of beta-glucuronidase and interleukin-1 beta decreased over time in the more involved lesions. These data suggest that the amount of proinflammatory mediators in the canal and periapical lesion is limited. Furthermore, IgM seemed to be a marker for the severity of periapical lesions. This may relate to vascular permeability that allows passage of this larger molecule into the extravascular environment.