40 subjects with a mandibular molar diagnosed with symptomatic irreversible pulpitis will be randomly allocated into 2 groups. One group will receive a total of 3 cartridges of a standard, unbuffered 2% lidocaine with 1:100,000 epinephrine via inferior alveolar nerve block (IANB) followed by supplemental buccal and lingual infiltrations, while the other will receive the equivalent yet buffered formulation. An electronic pulp tester (EPT) will be used to objectively determine baseline pulpal status of the affected tooth, followed by 2-minute interval testing following the administration of all local anesthesia. The onset of pulpal anesthesia is defined by the first of 2 consecutive EPT=80 readings, and the endodontic treatment may begin. Profound pulpal anesthesia is ultimately determined if the patients report a comfortable pulpotomy as reflected on the Wong-Baker FACES Visual Analog Scale.
The purpose of this study is to determine whether one type of anesthetic (numbing medicine) will work better at numbing the nerve in a tooth than using a different type of anesthetic. A second purpose is to see if the time needed to numb the nerve in a tooth is different between the two anesthetics.