Authors: Birchfield J, Rosenberg PA.
Title: Role of the anesthetic solution in intrapulpal anesthesia.
Journal: J Endod
Date: Jan 1975
Citation: 1(1):26-7
Category: Endodontic Pharmacology
Evidence-based Ranking: 4
Purpose/Objectives: To determine whether the anesthesia that is produced by intrapulpal injection is the result of the anesthetic solution per se or of other factors.

Materials/ Methods: 56 patients were selected in the endodontic clinic that had noticeable pain during the approach to the pulp , despite apparently profound anesthesia. The study was a double blinded study, once it was determined intrapulpal anesthesia was necessary, the operator was given 2% lido. w/ 1:50,000 epi or normal saline. The results were checked with an endodontic explorer and then extirpation of the pulp. . Results: A total of 56 intrapulpal injections were given, 28 on mandibular molars, 22 on mandibular premolars. 37 were given with normal saline and 19 were given with lidocaine. All injections except three were successful ( 2 saline, and 1 lido) and these three all had access to big to achieve backpressure.

AuthorÂ’s Conclusions: There was no difference in the intrapulpal anesthesia that was produced whether sterile saline solution or lidocaine 2% with 1:50,000 epi was used. Pressure seems to be the major factor in producing anesthesia.

ReviewerÂ’s comments: Supports the belief that pressure is the pain component to intrapulpal anesthesia. I questioned if it was a double blinded study, how come double the injections were performed with saline rather than lidocaine.