Does the presence and amount of epinephrine in 2% lidocaine affect its anesthetic efficacy in the management of symptomatic maxillary molars with irreversible pulpitis?

Abstract

Background This was a randomized controlled clinical trial that aimed to evaluate the anesthetic efficacy of 2% lidocaine combined with different concentrations of epinephrine (plain, 1:200,000 and 1:80,000) during endodontic treatment of maxillary molars with symptomatic irreversible pulpitis. Methods The trial included 144 adult patients who were randomly allocated to three treatment groups. All patients received buccal-plus-palatal infiltration. After 10 min, pulp sensibility testing was performed using an electric pulp test (EPT). If a tooth responded positively, anesthesia was considered to have failed. In the case of a negative EPT response, endodontic access was initiated under rubber dam isolation. The success of anesthesia was defined as having a pain score less than 55 on the Heft Parker visual analog scale (HP VAS), which was categorized as ‘no pain’ or ‘faint/weak/mild’ pain on the HP VAS. Baseline pre-injection and post-injection maximum heart rates were recorded. The Pearson chi-square test was used to analyze the anesthetic success rates at 5% significance. Results Plain 2% lidocaine and 2% lidocaine with 1:200,000 epinephrine and 1:80,000 epinephrine had anesthetic success rates of 18.75%, 72.9%, and 82.3%, respectively. Statistical analysis indicated significant differences between the groups (P < 0.001, χ 2 = 47.5, df = 2). The maximum heart rate increase was seen with 2% lidocaine solution with epinephrine. Conclusion Adding epinephrine to 2% lidocaine significantly improves its anesthetic success rates during the root canal treatment of maxillary molars with symptomatic irreversible pulpitis.

Physiology of pregnancy and oral local anesthesia considerations

“…The concentration of epinephrine added to 2% lidocaine is still controversial, and the dosage form of 1:80,000–1:200,000 epinephrine is more commonly used clinically ( Singla et al, 2022 ). Higher concentrations, such as 1:50,000, do not provide faster onset or longer duration for local oral anesthesia ( Dagher, Yared & Machtou, 1997 ; Wali et al, 2010 ).…”

Clonidine versus Adrenaline as an Adjunct to Lignocaine on Haemodynamic Parameters during Nerve Block for Third Molar Surgical Removal - A Systematic Review and Meta-Analysis

“…To prevent this, vasoconstrictor such as adrenaline is added to the local anaesthesia. [ 4 ] Adrenaline as a vasoconstrictor is used at varied concentrations according to the need i.e., 1:50,000, 1:80,000, 1:1,00,000 and 1:2,00,000. [ 5 ] Adrenaline increases cardiac stroke volume and hence is relatively contraindicated in heart diseases, uncontrolled hypertension and hyperthyroidism.…”