4% articaine buccal infiltration versus 2% lidocaine inferior alveolar nerve block for emergency root canal treatment in mandibular molars with irreversible pulpits: a randomized clinical study

Aim To compare the anaesthetic efficacy of inferior alveolar nerve blocks (IANB) with 1.8 mL of 2% lidocaine (LI) to a buccal infiltration (BI) with 1.8 mL of 4% articaine (AR), both with 1 : 100 000 epinephrine, in patients with symptomatic irreversible pulpits in a randomized controlled trial. Methodology Volunteers presenting at the Emergency Centre ( FOP ‐ UNICAMP ) were randomly divided into two groups (30 for AR and 20 for LI ). Operator and patient were not blinded. Success was recorded when complete pain‐free treatment was achieved after a single injection ( IANB or BI ) or when one supplemental injection was needed for emergency endodontic procedures. Success rate of supplemental injection was evaluated between and within groups using Fisher's exact test and chi‐square test. Results A higher success rate ( P  =   0.03/Fisher's exact test) was observed with AR (40%) than with LI (10%). No significant difference was found when a single injection plus one supplemental injection was compared between groups ( P  =   1.0; AR  = 70%; LI  = 80%). However, supplemental injection increased the anaesthetic success rates ( AR , P  =   0.04; LI , P  =   0.0001) within groups. Conclusions Single anaesthesia techniques ( IANB or BI ) were not able to achieve pain‐free emergency endodontic treatment. Supplemental anaesthetic techniques should be considered prior to treatment procedures in order to increase success rate (consort: registration number – NCT 01912755/Fapesp: #2009/10834‐4).