The use of an intra-oral injection of ketorolac in the treatment of irreversible pulpitis

AIM: To examine whether an intra-oral injection of a nonsteroidal anti-inflammatory drug (ketorolac), in association with conventional local anaesthetic techniques, would improve the pulp extirpation rate in teeth with irreversible pulpitis. METHODOLOGY: A two group double-blind clinical trial was undertaken in the Dental Casualty Department of the University of Manchester School of Dentistry. Patients were randomly allocated to either the test or control group. The test group received an intra-oral injection of ketorolac (30 mg in 1 mL) in the buccal sulcus adjacent to the tooth being treated. After an interval of 15 min, they then received 2.2 mL of 2% lidocaine with 1 : 80 000 epinephrine by buccal infiltration in the maxilla or by inferior dental block in the mandible. The control group received an intra-oral injection of normal saline (1 mL) in the buccal sulcus adjacent to the tooth being treated, followed by the same local anaesthetic regime as the test group after the 15 min interval. Fifteen minutes after the local anaesthetic injections, pulp extirpation was attempted. All patients completed the short-form McGill pain questionnaire prior to treatment and completed identical questionnaires at 6 and 24 h after treatment. RESULTS: The study protocol set the number of patients to be treated at twenty. However, as the study progressed it became apparent that the intra-oral injection of ketorolac caused significant pain to four of the five patients who received it; therefore the study was terminated after ten patients had been treated. The results from the patients treated showed no significant difference in the pulp extirpation rate between the test and control groups. However, patients with higher pain scores at baseline were less likely to have the pulp completely extirpated, irrespective of whether they were in the test or control group. Pain scores for all patients decreased significantly from baseline to 24 h. CONCLUSION: An intra-oral injection of ketorolac did not improve the pulp extirpation rate in a small group of patients with irreversible pulpitis compared with a placebo. In addition, it was associated with such significant pain on injection that it cannot be recommended as a treatment in this situation.