Where is the long buccal injection administered?

• A. Distal and buccal to the 2nd mandibular molar
• B. Mesial to the 1st premolar
• C. Buccal to the 3rd molar
• D. Lingual to the canine

Answer: (A)

The long buccal injection is given to block the long buccal nerve, which supplies the buccal mucosa and gingiva of the mandibular molars. The nerve runs along the buccal aspect near the molar roots as it courses toward the cheek, so placing anesthetic in the mucobuccal fold distal and buccal to the second mandibular molar directly addresses the nerve as it passes by. This location reliably anesthetizes the buccal tissues of the molar region without affecting deeper or other nerve branches.

Choosing a location mesial to the first premolar would target areas closer to other nerves (and not the long buccal), a position buccal to the third molar is farther back than the typical nerve path and may not reliably block it, and a site lingual to the canine would target the lingual nerve rather than the long buccal nerve.