The buccinator nerve (7) gives sensory supply to the cheeks and the buccinator muscle and sensation to the mucosa of the cheeks as far as the angle of the mouth.

The lingual nerve (8) runs downward and then forward to reach the ventral surface of the tongue, and supply sensation to the anterior two thirds of the tongue.

The mylohyoid nerve, branch of the inferior alveolar nerve, leaves the nerve near the mandibular foramen, and supplies the anterior belly of the digastric and mylohyoid muscle.

The lower portion of the parotid plexus of the facial nerve or the seventh cranial nerve supplies the sensation to those parts of the face such as the obicularis oris of the lower lip, the triangularis muscle and quadratus labi inferioris, resorius and also the muscle of the lower lip and chin.

Lymphatic Drainage of the Mandible

The lymphatic system is clinically significant because of its role in fighting infection. Lymph is a pale fluid consisting chiefly of blood plasma and white blood cells. The thin walled lymph vessels arise blindly in the intercellular spaces and follow a drain-age pattern similar to that of the veins. The ducts are constricted at intervals, and these constrictions correspond to the semilunar valves within the vessels. The lymph is conducted through afferent channels to lymph nodes grouped at strategic locations along the veins. These nodes are often the first sites at which pathologic processes manifest themselves. Therefore a knowledge of these nodes is important in the recognition, diagnosis and therapy of infections and malignant tumors.

      The lymph nodes of the head and neck consists of two anatomical groups : the superficial nodes and the deep nodes. Among the superficial nodes related to the mandible are the submandibular and the submental nodes. The submandibular nodes, 3-6 in number, are located beneath the body of the mandible, in the submandibular triangle on the submandibular gland. The submental nodes consist of 2-3 nodes located between the anterior bellies of the digastric muscles immediately beneath the mentis.
      The deep cervical nodes consist of a superior group located beneath the sternocleidomastoid muscle at the level of the thyroid cartilage (Adams Apple) grouped around the internal jugular vein and an inferior cervical aggregation arranged near the

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