Which nerve block is described for anesthesia of maxillary incisors using the height of the mucobuccal fold mesial to the canine?

Which nerve block is described for anesthesia of maxillary incisors using the height of the mucobuccal fold mesial to the canine?

• A. ASA block
• B. IO block
• C. PSA block
• D. Mental block

Answer: (A)

The block described is the anterior superior alveolar (ASA) block. Injecting at the height of the mucobuccal fold just mesial to the canine targets the anterior superior alveolar nerve, a branch of the infraorbital nerve, which supplies the maxillary incisors and canines along with their facial gingiva. Depositing anesthetic in this location allows diffusion to affect the nerves that innervate these front teeth, giving numbness to the central and lateral incisors and the canine on that side. Other blocks sit at different landmarks and cover different tooth groups: the infraorbital block is placed at the infraorbital foramen and tends to anesthetize a broader area including some of the premolars and canines, but not specifically at the mucobuccal fold mesial to the canine; the PSA block targets the molars and buccal gingiva; the mental block is for the lower jaw.

The block described is the anterior superior alveolar (ASA) block. Injecting at the height of the mucobuccal fold just mesial to the canine targets the anterior superior alveolar nerve, a branch of the infraorbital nerve, which supplies the maxillary incisors and canines along with their facial gingiva. Depositing anesthetic in this location allows diffusion to affect the nerves that innervate these front teeth, giving numbness to the central and lateral incisors and the canine on that side.

Other blocks sit at different landmarks and cover different tooth groups: the infraorbital block is placed at the infraorbital foramen and tends to anesthetize a broader area including some of the premolars and canines, but not specifically at the mucobuccal fold mesial to the canine; the PSA block targets the molars and buccal gingiva; the mental block is for the lower jaw.