A Double-Blind Comparison of a Supplemental Interligamentary Injection of Fentanyl and Mepivacaine with 1:200,000 Epinephrine for Irreversible Pulpitis

The analgesic efficacy of supplemental interligamentary fentanyl injection for management of endodontic debridement patients was investigated through a randomized, double-blind study. Forty patients who presented with acute symptomatic irreversible pulpitis of the upper first molar tooth participated in the study. Patients were scheduled for endodontic debridement, for which infiltration anesthesia with 1.8 ml of 2% mepivacaine with epinephrine 1:200,000 was the standard primary anesthetic technique. Patients were randomly divided into two equal groups. The first group received supplemental interligamentary injection with 0.4 ml fentanyl 0.05 mg/ml, while the second group received supplemental interligamentary injection with 0.4 ml mepivacaine with epinephrine 1:200,000. The intraligamental-injected drug was given as 0.2 ml on the mesial and 0.2 ml on the distal aspect of the tooth. Results indicated that fentanyl provided relatively greater analgesia, yielding satisfactory relief during different stages of the procedure, including access cavity preparation, pulpotomy, and pulp extirpation. Fentanyl is effective when used in conjunction with local anesthetics to provide adequate analgesia during endodontic debridement, and this finding provides strong evidence that peripheral actions are involved in the analgesia produced by opioid drugs in inflammatory pain.