Buffered 1% Lidocaine With Epinephrine Effective for Mandibular Nerve Block

Objectives: Assess outcomes for pain on injection and pulpal anesthesia for buffered 1% lidocaine vs. non-buffered 2% lidocaine both with 1/100k epinephrine.
Methods: In an IRB-approved randomized crossover trial, buffered 1% lidocaine was compared to non-buffered 2% lidocaine. After mandibular nerve block with 40mg. of buffered lidocaine or 80mg. of non-buffered lidocaine, subjects reported pain on injection with a 10pt Likert-type scale and responses at the mandibular 1^st molar and canine after cold and electrical pulp testing(EPT). Teeth were tested prior and at 30-minute intervals until a positive response returned. Two weeks later, subjects were tested with the alternate drug combinations.

Predictor variables were alternate drug formulations. Outcome variables were subjects’ responses to pain on injection and to cold and EPT stimulation. Statistical analyses Proc TTEST (SAS v 9.3, SAS Institute, Cary, NC), with the crossover option for a two period crossover design, analysed outcomes. Significance was set at P<0.05.
Results: 57% subjects were female, 70% Caucasian, 17% African American, 13% other. Median age was 25 years(IQR 21,26y) with median body weight 140lbs(IQR 120,155lbs).

Median time to sensation return between the two drug formulations was 0 for all pulp tests. Time was not significantly different for; cold test on a molar (P=0.74,95% CI:-0.49,0.57), cold test on a canine (P=0.50,95% CI:-0.89,0.52), or EPT on a canine (P=0.52,95% CI:-0.58,0.30). Time was marginally significantly different between the two drug formulations for the EPT on a molar (P=0.05,95% CI:-1.34,0.20). 70% subjects reported lower pain scores with the buffered drug vs. the non-buffered, P<0.01.
Conclusions: Buffered lidocaine with epinephrine can produce similar clinical outcomes after mandibular nerve block with lower dosage as compared to unbuffered lidocaine.