EFFECTIVENESS OF VARIOUS MEDICATIONS ON POSTOPERATIVE PAIN FOLLOWING COMPLETE INSTRUMENTATION

The root canals of 588 consecutive nonsurgical patients with varying l evels of pain were completely instrumented in 10 endodontic practices and 4 endodontic graduate programs. The participants were sequentially assigned to one of nine medications and a placebo. The severity of pa in was assessed by the visual analog scale for 72 h following instrume ntation. Among all of the parameters studied, three factors (preoperat ive pain, apprehension, and types of medication) were found to be sign ificant in determining postinstrumentation pain. An association was fo und between the intensity of pre- and postoperative pain. As the inten sity of preoperative pain increased, the chances for more severe posto perative pain increased (p < 0.0001). In addition, an association betw een the presence of apprehension before any treatment and postoperativ e pain was also noted (between 0.012 < p < 0.047). Examination of the time-effect curves for various medications in patients with no or mild pain showed no statistical significant difference between the effecti veness of different medications and placebo. However, a multiple compa rison of the effectiveness of various medications and placebo on patie nts in moderate and severe preoperative pain showed that ibuprofen, ke toprofen, erythromycin base, penicillin, and methylprednisolone plus p enicillin were more effective than placebo within the first 48 h follo wing complete instrumentation.