Submandibular triangle


The submandibular triangle corresponds to the region of the neck immediately beneath the body of the mandible.

Boundaries and coverings

It is bounded:
  • above, by the lower border of the body of the mandible, and a line drawn from its angle to the mastoid process;
  • below, by the posterior belly of the Digastricus; in front, by the anterior belly of the Digastricus.
It is covered by the integument, superficial fascia, Platysma, and deep fascia, ramifying in which are branches of the facial nerve and ascending filaments of the cutaneous cervical nerve.
Its floor is formed by the Mylohyoideus anteriorly, and by the hyoglossus posteriorly.

Triangles

  • Beclard Triangle
  • Lesser Triangle
  • Pirogoff Triangle

    Divisions

It is divided into an anterior and a posterior part by the stylomandibular ligament.

Anterior part

The anterior part contains the submandibular gland, superficial to which is the anterior facial vein, while imbedded in the gland is the facial artery and its glandular branches.
Beneath the gland, on the surface of the Mylohyoideus, are the submental artery and the mylohyoid artery and nerve.

Posterior part

The posterior part of this triangle contains the external carotid artery, ascending deeply in the substance of the parotid gland
This vessel lies here in front of, and superficial to, the external carotid, being crossed by the facial nerve, and gives off in its course the posterior auricular, superficial temporal, and internal maxillary branches: more deeply are the internal carotid, the internal jugular vein, and the vagus nerve, separated from the external carotid by the Styloglossus and Stylopharyngeus, and the hypoglossal nerve

Additional images

Summary of contents

The following summarizes the important structures found in the submandibular triangle:
  1. Submental artery
  2. Ascending palatine artery
  3. Glandular branches to the submandibular branch
  4. Tonsillar branch to palatine tonsil