Before beginning endodontic access, what is the MOST reliable way to confirm that PULPAL anesthesia has been achieved?

Correct answer: A. Apply a cold test to the tooth and confirm no response

• A. CORRECT. A COLD test (or an electric pulp test) applied to the tooth itself is the only bedside test that interrogates the PULPAL nerve supply directly. Absence of response to a stimulus that previously produced pain is objective evidence of pulpal anesthesia. This matters most in symptomatic irreversible pulpitis of mandibular molars, where an inferior alveolar block produces profound lip numbness yet still fails to anesthetise the pulp in a substantial proportion of cases.
• B. Lip numbness confirms only that the anesthetic reached the mental/incisive branches — that is SOFT-TISSUE anesthesia. A numb lip with a live pulp is the single commonest cause of an unpleasant surprise on access.
• C. A vague subjective impression that the tooth 'feels different' is unreliable and does not test the pulpal nerve supply.
• D. Probing the sulcus tests the periodontal soft tissues supplied by different fibres, not the pulp.

Note: If a cold test still elicits a response after a mandibular block, add a supplemental technique: buccal ARTICAINE infiltration, an intraligamentary (PDL) injection, or an intraosseous injection. Intrapulpal injection is the last resort once the chamber is open.