Differences between the sexes in post-surgical pain

It has been shown that women have a lower pain threshold and lower toleranc e to some forms of experimental pain then men. However, the evidence that c linical pain is perceived differently by the two sexes is not yet as strong . The placement of intraoral implants is a highly controlled surgical proce dure that we have used to investigate this possibility. Forty-eight edentul ous (without teeth) subjects (27 females), aged from 35 to 63 years, receiv ed two titanium implants in the anterior mandible under local anesthesia. A fter the surgery, subjects completed a pain diary three times each day, rat ing pain intensity and unpleasantness on 100 mm visual analog scales (VAS). Once a day, they chose verbal descriptors from the McGill Pain Questionnai re (MPQ). Age of subjects, duration of surgery, the amount of local anesthe tic used and the amount of pain medication taken were not statistically dif ferent for the two groups (P greater than or equal to 0.32). Results showed that the senior surgeon produced significantly less pain than a 4th year r esident (P = 0.04). Although there were no significant differences between sexes for mean daily ratings of intensity or unpleasantness over time (P gr eater than or equal to 0.10), most women experienced the highest intensity of pain during the day, while most men had higher pain in the evening (P = 0.025). Also, the relative unpleasantness (unpleasantness/intensity ratio) increased significantly with time for males, but not for females (P = 0.016 ). Males and females did not differ in the total number of words chosen fro m the MPQ (P = 0.61), or in the averaged Pain Rating Index (PRI) (P = 0.53) . However, women used significantly more evaluative words than men (P = 0.0 4), suggesting that woman found the overall intensity greater. These result s indicate that women find post-surgical pain more intense than males, but that men are more disturbed than women by low levels of pain that last seve ral days. (C) 2000 International Association for the Study of Pain. Publish ed by Elsevier Science B.V. All rights reserved.