The effect of inferior alveolar nerve block anesthesia of 4% articaine and epinephrine 1:100,000 on blood flow and anesthesia of human mandibular teeth

BACKGROUND/PURPOSE: Local anesthetics and anesthetic techniques affect the patterns of pulpal blood flow (PBF) and pulpal anesthesia in human teeth. This study aimed to determine PBF changes and pulpal anesthesia of intact mandibular first molars and canines after administration of 4% articaine with epinephrine 1:100,000 using inferior alveolar nerve block (IANB). MATERIALS AND METHODS: Ten healthy subjects received IANB of 4% articaine with epinephrine 1:100,000. Laser Doppler flowmetry and electrical pulp testing were combined to assess PBF changes and pulpal anesthesia of intact mandibular first molars and canines. The data were analyzed using one-way repeated-measures analysis of variance and Student–Newman–Keuls test. RESULTS: IANB with 4% articaine and epinephrine 1:100,000 did not have any significant change in PBF for the first 20 min post injection in mandibular first molars, and for 45 min post injection in the canines (P > 0.05). However, a hyperemic response occurred during 25–60 min post injection in the molars, and between 60 and 75 min post injection in the canines (P < 0.05). Thereafter, the PBF in both teeth returned to the baseline. Onset of pulpal anesthesia was 8.60 ± 2.12 min in the molars, and 9 ± 1.94 min in the canines. Duration of pulpal anesthesia was 82.40 ± 41.56 min in the molars, and 84 ± 47.40 min in the canines. CONCLUSION: In case of successful IANB, 4% articaine and epinephrine 1:100,000 caused insignificant changes in PBF up to 30 min but a hyperemic response at later time points. Thereafter, the PBF returned to the baseline.