Anesthetic Efficacy of Gow-Gates, Vazirani-Akinosi, and Mental Incisive Nerve Blocks for Treatment of Symptomatic Irreversible Pulpitis: A Systematic Review and Meta-analysis with Trial Sequential Analysis

INTRODUCTION: This systematic review compared the anesthetic efficacy between Gow-Gates (GG), Vazirani-Akinosi (VA), and mental incisive (MI) nerve blocks (NBs) with inferior alveolar nerve blocks (IANBs) in mandibular teeth with irreversible pulpitis using meta-analysis and trial sequential analysis (TSA).

METHODS: Studies were identified from 4 electronic databases up to June 2019. Randomized clinical trials (RCTs) comparing the anesthetic success rate of GG, VA, and MI NBs with IANBs in mandibular premolars and molars with irreversible pulpitis were included. The quality of selected RCTs was appraised using the revised Cochrane risk of bias tool. Random-effects meta-analyses of risk ratio (RR) and 95% confidence intervals (CIs) were calculated, and random errors were evaluated by TSA. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation approach.

RESULTS: Five RCTs were included; 2 of them were classified as low risk of bias. No significant difference was observed in the anesthesia success rate compared between GG and IA NBs (RR = 1.10; 95% CI, 0.82-1.48; I2 = 0%). Similarly, no difference was evident between MINB and IANB (RR = 1.15; 95% CI, 0.97-1.36; I2 = 0%). Overall, the cumulative success rates for the 3 anesthetic techniques were low. TSA showed a lack of firm evidence for the results of the meta-analysis between GG NB and IANB. The Grading of Recommendations, Assessment, Development and Evaluation approach evaluation showed that the evidence was of moderate quality for GG NB and IANB compared with low quality for MI and IA NBs. Because only 1 study was available comparing VA NB and IANB, a meta-analysis was not performed. The adverse effect associated with MI NB was swelling, whereas it was prolonged numbness for IANB.

CONCLUSIONS: GG NB and IANB showed similar anesthetic efficacy compared with IANB in mandibular teeth with irreversible pulpitis. However, the success rates for each technique indicate the need for supplemental anesthesia. Further well-designed RCTs evaluating different anesthetic techniques with and without supplemental injection are required to provide stronger evidence.