More Pain Before Root Canal, Less to Gain from Anesthesia

Local anesthetics are a necessary first step for any root canal. However, one study published in the journal Anesthesia Progress has uncovered that the standard dosage may not be enough to curb pain for patients experiencing severe toothaches.

To observe whether a patient’s pain level before a root canal changed the effectiveness of local anesthesia, researchers tracked the pain intensity (from mild to moderate to severe) of 175 adults prior to their root canal. All patients were given a standard local anesthetic and the injection was considered ineffective if the patient continued to feel pain during the procedure.

The results showed that 1) age and gender did not affect the effectiveness of the anesthetic and 2) patients who experienced more pain before the root canal were more likely to feel pain during the procedure. In fact, 33% of patients with mild pain felt little to no pain during the procedure, but only 16% of patients with severe pain had a painless surgery. This is because a patient with extreme pain has overly active nerves, so the patient’s lip may be numb after local anesthesia has been administered, but the standard dose of anesthesia can’t block pain once dental instruments enter the mouth.

To ensure a painless root canal procedure, it is important for dentists to ascertain just how much a patient’s tooth hurts. For patients with severe pain, clinicians should administer a supplementary injection as well as a primary injection, since such patients are predisposed to a high anesthetic failure rate.