You are extracting tooth #9. Which arterial branches supply the field you are anaesthetising?

Correct answer: A. The anterior superior alveolar branch of the infraorbital artery and the sphenopalatine/nasopalatine supply

• A. CORRECT. Tooth #9 (maxillary left central incisor) receives its labial/pulpal supply from the ANTERIOR SUPERIOR ALVEOLAR artery, a branch of the INFRAORBITAL artery (itself a branch of the third part of the maxillary artery). Its palatal soft tissue is supplied by the NASOPALATINE branch of the sphenopalatine artery, emerging through the incisive foramen. Both territories are branches of the maxillary artery.
• B. Lingual and facial arteries arise from the external carotid and supply the tongue and face; they are not the arterial supply of a maxillary incisor.
• C. Inferior alveolar and buccal arteries supply the MANDIBLE and cheek, not a maxillary central incisor.
• D. PSA and greater palatine supply the maxillary POSTERIOR teeth and the posterior hard palate — the wrong end of the arch.

Note: Source keyed 'ASA and infraorbital,' which is really one pathway (ASA is a branch OF the infraorbital). The palatal counterpart for #9 is nasopalatine. Worth clarifying with the group.