Comparative evaluation of 2% mepivacaine and 2% lidocaine for inferior alveolar nerve block: a double-blind randomized clinical trial

ABSTRACT

Objective

Lidocaine is the standard dental local anesthetic, while mepivacaine is gaining use despite higher cost and limited comparative data. This study compared the anesthetic efficacy (onset, duration, success rate) of 2% lidocaine with 1:100,000 epinephrine versus 2% mepivacaine with 1:100,000 epinephrine for inferior alveolar nerve block (IANB) in healthy young adults. A secondary aim was to assess whether lidocaine could serve as a cost-effective alternative without reduced clinical performance, particularly when administered by undergraduate dental students.

Method

A double-blind, randomized clinical trial was conducted involving 62 healthy dental students aged 19–21 years. Participants were randomly assigned to receive either 2% lidocaine or 2% mepivacaine with 1:100,000 epinephrine via conventional IANB technique. The onset time was assessed by pin-prick and cold testing, while the duration of anesthesia was determined by participant self-report. Anesthetic success was defined as achieving effective anesthesia within 10 min post-injection. Adverse events were recorded throughout the study. Group comparisons were analyzed using independent t-tests and chi-square tests, with statistical significance set at P < 0.05.

Results

The mean onset time was 5.17 ± 1.96 min for lidocaine and 5.52 ± 1.57 min for mepivacaine (P = 0.435). The mean duration of anesthesia was 214.25 ± 47.52 min for lidocaine and 234.32 ± 39.02 min for mepivacaine (P = 0.073). The success rate within 10 min was 78.6% for lidocaine and 91.2% for mepivacaine, though the difference was not statistically significant. Gender-based subgroup analysis showed no significant differences in anesthetic response. Both anesthetics were well tolerated, with only one minor adverse event reported in the mepivacaine group.

Conclusion

For inferior alveolar nerve blocks in healthy young adults, lidocaine and mepivacaine performed similarly in terms of onset, duration, and success rate when administered by undergraduate dental students. This suggests both agents provide predictable anesthesia. Given its lower cost and comparable performance, lidocaine may represent a cost-conscious option for routine dental anesthesia. More extensive research with diverse patient groups and operator experience levels is needed to confirm these findings and broaden their applicability.

Clinical trial registration

Registration number is “TCTR20250106002”, and date of registration is 06/01/2025, https://www.thaiclinicaltrials.org/show/TCTR20250106002.