Mandibular foramen

The Mandibular foramen is an opening on the internal surface of the ramus (posterior and perpendicularly oriented part of the mandible) for divisions of the mandibular vessels and nerve to pass.

Contents
The mandibular nerve is one of three branches of the trigeminal nerve (CN V) and the only branch with motor innervation.

The inferior alveolar nerve and inferior alveolar artery enter the foramen traveling through the body and exit at the mental foramen on the anterior mandible at which point the nerve is known as the mental nerve.

These nerves provide sensory innervation to the lower teeth, as well as the lower lip and some skin on the lower face.

Structures of rim
There are two distinct anatomies to its rim.
 * In the common form the rim is “V” shaped, with a groove separating the anterior and posterior parts.
 * In the horizontal-oval form there is no groove, and the rim is horizontally oriented and oval in shape, the anterior and posterior parts connected.