Abstract:

Objective　To compare the endotoxin levels between acute and chronic periapical periodontitiswith different clinical symptoms.Methods　10 cases of acute periapical priodontitis(Group 1) ,10 cases of chronic periapical periodontitis(group 2, the diameter of apical radiolucency area was less than 2 mm),10 cases of chronic periapical periodontitis with sinus(group 3, the diameter of apical radiolucency area was greater than 2 mm), 10 cases of chronic periapical periodontitis without sinus (group 4, the diameter of apical radiolucency area was greater than 2 mm), were included in the study. Chromogenic substrate method of limulus amebocyte lysate(LAL) test was used to measure the endotoxin level.Results　Endotoxin concentrations in group 2 were significantly lower than those in group 1, group 3 and group 4(P<0·01).Conclusion　Endotoxin plays a very important role in the initiation and development of periapical periodotitis and is closely associatedwith clinical symptoms and apical radiolucency de- gree.

Key words: periapical periodontitis, endotoxin, bacteria