Anesthetic Efficacy of 1.8 Milliliters and 3.6 Milliliters of 2% Lidocaine with 1:100,000 Epinephrine for Posterior Superior Alveolar Nerve Blocks

Abstract 

Introduction

The purpose of this prospective, randomized, single-blinded study was to measure the degree of anesthesia obtained with 1.8 mL and 3.6 mL of 2% lidocaine with 1:100,000 epinephrine in posterior superior alveolar (PSA) nerve blocks.

Methods

Thirty-one adult subjects randomly received PSA nerve blocks of 1.8 mL and 3.6 mL of the lidocaine solution at 2 separate appointments in a crossover design. An electric pulp tester was used to test for anesthesia of the first and second molars and premolars in 3-minute cycles for 50 minutes. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes.

Results and Conclusions

Anesthetic success for the 1.8 mL volume of 2% lidocaine with 1:100,000 epinephrine was 97% for the second molar and 77% for the first molar. Anesthetic success for the 3.6 mL volume of 2% lidocaine with 1:100,000 epinephrine was 100% for the second molar and 84% for the first molar. The differences were not statistically significant between the 2 anesthetic volumes. Anesthetic success for the premolars for both volumes was in the low to moderate range and would not provide predictable pulpal anesthesia. For the first molar, the 3.6 mL volume of the lidocaine formulation provided a statistically longer duration of pulpal anesthesia than the 1.8 mL volume. The pain of depositing a 3.6 mL volume of a lidocaine solution was not statistically more painful than depositing a 1.8 mL volume.

Key Words: Lidocaine, maxillary, posterior superior alveolar nerve block, PSA