Efficacy of mental-incisive nerve block in root canal treatment of mandibular first molars with asymptomatic irreversible pulpitis: a randomized controlled trial

The aim of this study was to evaluate the effect of mentalincisive
nerve block (MINB) along with finger pressure following
inferior alveolar nerve block (IANB) on anesthetic
success in mandibular first molars with asymptomatic
irreversible pulpitis. In this randomized controlled trial, 70
patients were randomly divided into 2 groups (n = 35).
Each patient in the control group received only a standard
IANB injection of 1.8 mL of 2% lidocaine with 1:100,000
epinephrine. The injection was administered within 1
minute, using a standard aspirating dental cartridge
fitted with a 27-gauge dental needle. In the intervention
group, 15 minutes after injection of the standard IANB as
described for the control group, each patient received a
standard MINB injection of 1 mL of 2% lidocaine containing
1:100,000 epinephrine, administered by an operator not
involved in assessing the outcomes. After the MINB injection,
the patient applied firm finger pressure to the soft
tissue of the mental foramen region for 1 minute using the
hand on the side opposite to the injection. Objective assessment
of tooth anesthesia was carried out with electric
pulp tests (EPTs). In addition, the patients rated their pain
during the initial steps of endodontic treatment based
on a visual analog scale (VAS). The Mann-Whitney U and
Wilcoxon tests were used for the analysis of data. Of the
35 patients in each group, 20.0% (7 patients) in the control
group and 71.4% (25 patients) in the intervention group
had no response to EPTs 15 minutes after injections; this
difference was statistically significant (P < 0.05). The VAS
pain scores were significantly higher in the control group
than in the intervention group (P = 0.001). The administration
of MINB with pressure following IANB significantly
improved the success of anesthesia in mandibular first
molars with asymptomatic irreversible pulpitis