Sodium bicarbonate-buffered lidocaine may be superior to nonbuffered lidocaine in reducing onset time and injection pain during inferior alveolar nerve block (IANB), according to a systematic review published in the Journal of Dental Anesthesia and Pain Medicine.
For this systematic review, investigators examined randomized, double-blind studies from several databases, including PubMed, Web of Science, Cochrane Library, Embase, and Proquest that evaluated the use of buffered vs nonbuffered lidocaine during IANB (n=11). Study outcomes included onset time, injection pain assessed using a visual analog scale (VAS), percentage of painless injections, and anesthetic success rate of IANB.
The risk for bias was unclear in 10 of the 11 studies and high in 1 study. Buffered vs nonbuffered lidocaine was found to have a faster onset time (48-second difference; 95% CI, −42.06 to −54.40; P <.001), and lower VAS injection pain score (5.0-unit reduction on a scale of 0 to 100; 95% CI, −9.13 to −0.77; P =.02). The percentage of participants with painless injection (P =.059) and success rate (P =.290) were comparable in both groups.
However, the researchers cautioned that the studies included in their review had low-to-moderate quality evidence and that additional studies with larger numbers of participants and low risks for bias are needed to confirm these results.
Guo J, Yin K, Roges R, Enciso R. Efficacy of sodium bicarbonate buffered versus non-buffered lidocaine with epinephrine in inferior alveolar nerve block: a meta-analysis. J Dent Anesth Pain Med. 2018;18:129-142.