The mental nerve block anaesthetises the inferior alveolar branches of the mandibular nerve rostral to the 2nd premolar tooth. It is used for procedures on canine and incisor teeth.
An intra-oral approach is used to locate the mental foramen on the buccal surface of the mandible caudal to the lip frenulum ventral to the 2nd premolar tooth. A 30 gauge short needle is recommended. The upper lip is raised and the lower lip pulled ventrally to expose the frenulum. The bevel of the needle is orientated towards the bone. Insert the needle through the mucosa cranial to the frenulum towards the foramen. Advance the needle slowly until it enters the foramem. The general depth of penetration is 2-3mm in the cat, 5mm in a dog. Aspirate. Slowly deposit 0.1mls (cat) and 0.5mls (dog) over 60 seconds. Maximum volume is 1 cartridge per 10 kg body weight total volume in all sites. Slowly withdraw the needle. Wait for the anaesthetic to work.
Mandible of a dog demonstrating position of mental formamen (distal mental formamen [left] and middle mentalforamen [right].
Middle mental nerve block in a dog. Insertion of the needle through the mucosa towards the middle mental foramen.
Mandible of a cat demonstrating position of the middle mental formamen.
Middle mental nerve block in a cat. Insertion of the needle through the mucosa towards the middle mental foramen.