Fibrinolytic activity of blood and saliva before and after oral surgery

Blood and saliva samples were collected from 120 healthy persons whose bilateral mandibular impacted molars were to be removed surgically. The samples were collected at preoperative examination, immediately after the operation and in the postoperative period. The fibrinolytic activity of the euglobulin fractions, precipitated at pH 5.9 from plasma and mixed saliva, was measured by the fibrin plate method. The clinical variables were: age, sex, use of peroral contraceptives and menstrual cycle, daily tobacco consumption, duration of operation and amount of local anesthetic. The fibrinolytic activity of blood was lower in smokers than in nonsmokers (P less than 0.01). Women taking oral contraceptives showed higher fibrinolytic activity in blood and saliva (P less than 0.01). Multiple regression analysis revealed that the following independent variables were significant as predictors estimating the postoperative fibrinolytic activity of blood (R2 = 0.42, P less than 0.001): preoperative fibrinolytic activity, operation time, tobacco consumption and amount of local anesthesia. No relationship was demonstrated between the preoperative fibrinolytic activity in blood and mixed saliva, whereas postoperative fibrinolytic activity in blood significantly influenced the activity in saliva, because of direct contamination from the oral ulcer (P less than 0.05). Patients who developed alveolitis sicca dolorosa ("dry socket") showed significantly higher fibrinolytic activity in the blood postoperatively (P less than 0.01).