Methods: 230 oral surgery patients participated in the study. Prior to surgery, a number of questionnaires were filled out (anxiety, experience with needles, oral surgery data etc.) and an instruction was given about raising the hand as long as pain was felt as a result of the injection, and lowering the hand as soon as pain was gone. Next, pain intensity and pain duration (using a stopwatch) as a result of the injection were measured.
Results: In general, patients expect (m=4.2, sd=2.7) more pain than they experience (m=2.6, sd=2.2). However, 8.3% of patients reported a score in the range 7-10. A total of 61 patients raised their hand to indicate duration of pain. On average, pain lasted for 5.3 sec (range 1-24.5 sec), about 36% of patients raised their hand for 2 sec or less, and 14.6% raised their hand for 10 sec or more.
Conclusion: In general, a mandibular block injection can be considered as a mildly painful experience, lasting only a few seconds. However, a small part of our patients (about 10%) do report high levels of pain, which last for considerable time. Unfortunately, it was not possible to predict, based on the measures used in this study, which patients would experience the mandibular block injection as an extremely painful event. In a future study, physiological measures and other psychological measures will be included.