A patient presents with a posterior crossbite on the left side involving teeth #14 (maxillary left first molar) and #19 (mandibular left first molar). After giving an IAN block, the patient still experiences pain during treatment. What is the appropriate supplemental anesthetic technique?

When an IAN block fails to provide complete anesthesia for a mandibular molar (as evidenced by pain during treatment despite soft-tissue anesthesia), the most evidence-based supplemental technique is a buccal infiltration with 4% articaine. Articaine's unique thiophene ring enhances its lipid solubility and allows it to diffuse through mandibular cortical bone more effectively than other local anesthetics, making it successful as a supplemental technique even in the mandible. Mepivacaine (carbocaine) and 2% lidocaine have less evidence for this supplemental use. Dismissing the patient's pain is ethically inappropriate.