Anesthetic efficacy of the supplemental intraosseous injection of 3% mepivacaine in irreversible pulpitis

Abstract

Objective: To determine the efficacy of a supplemental intraosseous injection of 3% mepivacaine in mandibular posterior teeth with irreversible pulpitis. Intraosseous injection pain, subjective heart rate increase, and pain ratings during endodontic treatment were also assessed.

Study design: Forty-eight patients with irreversible pulpitis received conventional inferior alveolar nerve blocks. Electric pulp testing was used to determine pulpal anesthesia. Patients who were positive to the pulp testing, or negative to pulp testing but felt pain during endodontic treatment, received an intraosseous injection of 1.8 ml of 3% mepivacaine. A second intraosseous injection of 3% mepivacaine (1.8 ml) was given if the first injection was unsuccessful.

Results: Seventy-five percent of patients required an initial intraosseous injection because of failure to gain pulpal anesthesia. The inferior alveolar block was 25% successful; the first intraosseous injection increased success to 80%. A second intraosseous injection further increased success to 98%. These differences were significant (p < 0.05). Eight percent (4/48) of the initial intraosseous injections resulted in solution being expressed into the oral cavity: these were considered technique failures.

Conclusions: For mandibular posterior teeth with irreversible pulpitis, a supplemental intraosseous injection of 3% mepivacaine increased anesthetic success. A second intraosseous injection, when necessary, further improved success.