Evaluation of the effectiveness of local anesthesia approaches for symptomatic irreversible pulpitis: a systematic review and meta-analysis

Objective This meta-analysis assessed the efficacy of various anesthetic protocols for symptomatic irreversible pulpitis, comparing techniques and agents to identify the optimal anesthesia approach. Methods We conducted a comprehensive search of the Cochrane Library, PubMed, Web of Science, Scopus, and Embase databases up to July 10, 2025, identifying relevant studies based on predefined inclusion and exclusion criteria. The primary outcome was the success rate of anesthesia. Data extraction and quality assessment were performed using a pre-designed form and the revised Cochrane Risk of Bias Tool. A fixed-effect model was used for meta-analysis when heterogeneity was low ( I 2 ≤ 50%, p ≥ 0.1); otherwise, a random-effects model was adopted. Additionally, another model was employed for validation, and the results from both models were compared to derive more reasonable conclusions. Publication bias was assessed using funnel plots and the Egger test. Results Fourteen RCTs were included in the meta-analysis. Pooled analysis showed that modified anesthetic protocols for SIP were 3.62 times more successful than conventional inferior alveolar nerve block (IANB) using standard 2% lidocaine with epinephrine (OR = 3.34; 95% CI: 2.49–4.48). Studies conducted in Iran had the highest success rate (OR = 4.31; 95% CI: 3.59–5.17, p < 0.001). Inferior alveolar nerve block (IANB) was more effective than buccal infiltration (OR = 4.03; 95% CI: 3.38–4.81, p < 0.001), and 4% articaine demonstrated the highest efficacy (OR = 4.18; 95% CI: 2.85–6.16, p < 0.001). Conclusion This meta-analysis assessed the efficacy of various anesthetic protocols for SIP, comparing techniques and agents to identify the optimal anesthesia approach. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/recorddashboard , PROSPERO database CRD42025638427.