Inferior Alveolar Nerve

Written by Aminah H Nurmamade

Last updated September 14, 2025
10 Revisions

The inferior alveolar nerve is a mixed nerve of the head and neck region. It is a branch of the mandibular division of the trigeminal nerve.

It supplies sensation to the teeth, lower lip, and chin, as well as motor innervation to the mylohyoid and anterior belly of the digastric.

Pro Feature - 3D Model

Course

The inferior alveolar nerve arises within the infratemporal fossa as a branch of the posterior division of the mandibular nerve.

It descends posterior to the lateral pterygoid muscle and lingual nerve. It gives rise to a motor branch to the mylohyoid muscle, before entering the mandibular canal via the the mandibular foramen.

Within the mandibular canal, the inferior alveolar nerve forms the inferior dental plexus and then gives rise to the incisive nerve. It terminates as the mental nerve, which exits the canal through the mental foramen.

Fig 1
The inferior alveolar nerve

Motor Supply

The inferior alveolar nerve provides motor fibres via the nerve to mylohyoid.

It arises from the inferior alveolar nerve just proximal to the mandibular canal. It supplies the mylohyoid muscle and the anterior belly of the digastric.

Fig 2
Lateral view of the neck with three of the suprahyoid muscles highlighted (digastric, mylohyoid and stylohyoid)

Sensory Supply

The inferior alveolar nerve provides sensory fibres through several branches:

  • Inferior dental plexus – supplies the mandibular molars and premolars
  • Incisive nerve – supplies the mandibular first premolar, canine, and incisors, together with their associated gingivae
  • Mental nerve – supplies the lower lip, skin of the chin, and gingivae of the anterior mandibular teeth