Enhancing inferior alveolar nerve block success in symptomatic irreversible pulpitis: Evidence-based clinical and adjunctive strategies

Dear Editor,

Unlike maxillary teeth, achieving consistent pulpal anesthesia in mandibular teeth with symptomatic irreversible pulpitis (SIP) is a treatment challenge.^[1] Despite being the most used method of mandibular anesthesia, the inferior alveolar nerve block (IANB) has a significantly lower success rate in SIP, with failure rates as high as 30–80%. Tetrodotoxin-resistant sodium channel expression, altered nociceptor thresholds, and inflammatory sensitization are the main causes of this complex issue. The necessity for supplementary techniques to improve anesthetic predictability is justified by these mechanisms. Multiple evidence-based approaches have been shown to improve IANB outcomes in SIP:

1. Preoperative nonsteroidal anti-inflammatory drug and analgesic premedication: Ibuprofen, ketorolac, or combined ibuprofen–acetaminophen regimens decrease inflammatory mediators and enhance anesthetic efficacy

2. Supplemental intraligamentary, intraseptal, or intraosseous anesthesia: When the primary IANB is insufficient, periodontal ligament injections or intraosseous systems (Stabident, X-Tip, Intraflow) provide rapid and profound pulpal anesthesia^[2]

3. Buccal infiltration using 4% articaine: Supplemental articaine infiltration improves pulpal anesthesia in mandibular molars due to enhanced bone penetration

4. Alternative block techniques: Gow-Gates and Vazirani–Akinosi blocks reduce technique- and anatomy-related failures and may improve success in refractory cases^[3]

5. Buffering and warming of anesthetic solutions: Sodium bicarbonate buffering increases anesthetic onset and success, while warming improves patient comfort and may aid anesthetic diffusion

6. Adjunctive corticosteroids and long-acting analgesics: Preoperative dexamethasone reduces inflammatory pain pathways, indirectly supporting anesthetic effectiveness.

7. Preoperative alprazolam for anxiety management: Anxiety amplifies pain perception and contributes to anesthetic resistance. Low-dose alprazolam, when medically appropriate, stabilizes patient anxiety, reduces sympathetic arousal, and may enhance IANB success

8. Aromatherapy as a non-pharmacologic adjunct: Lavender and rose aromatherapy have been shown to have anxiolytic effects. Anesthetic efficacy may be supported by lowering preoperative anxiety, which can enhance pain thresholds and patient cooperation. Preoperative preparation can include this straightforward, non-invasive procedure^[4,5]

9. Intra-pulpal injection: When all other approaches are unsuccessful, intra-pulpal injection administered under firm back pressure offers quick and dependable anesthesia, allowing endodontic treatment to be completed comfortably. A useful, multimodal strategy for resolving IANB failures in SIP is the combination of pharmacologic, non-pharmacologic, and technique-based approaches. When used with well-established anesthetic procedures, adjuncts such as aromatherapy and preoperative alprazolam expand the possibilities of patient-centered pain and anxiety management and may help clinicians achieve more consistent results. To validate and improve these integrated treatments, more controlled clinical trials are encouraged.