This is the median sagittal section of head and neck in which we will mainly see the features here in the oral cavity which is occupied by the tongue here. This is the tongue. The roof of the oral cavity is formed by the palate. Anteriorly this is the hard palate. Posteriorly this is the soft palate.
The muscles of the soft palate include tensor vali palatini, levator vali pelletini, musculus uvulae, palatoglossus and palatopharyngeus muscles. This is the uvula. All the muscles of the soft palate are supplied by the pharyngeal plexus or vagal accessory complex mainly containing the cranial accessory fiber through the vagus nerve except the tensor vali pelletini which is supplied by mandibular nerve.
This is the mandible here. Below and behind this is the hyoid bone. This is the tongue whose main bulk is formed by this fan shaped muscle which is known as genioglossus.
All the muscles of tongue intrinsic and extrinsic are supplied by hypoglossal nerve except palatoglossus muscle which is supplied by the vagal accessory complex that is the cranial accessory via vagus nerve. Below genioglossus we can see here from mandible to hyoid this is the geniohyoid muscle. Geniohyoid muscle is supplied by C1 through hypoglossal nerve below which we can see this is the myelohyoid muscle. The myelohyoid muscle is supplied by nerve to myelohyoid branch of inferior alveolar nerve and the inferior alveolar nerve is one of the branches of posterior division of mandibular nerve that is the third division of the trigeminal nerve.
Behind the tongue this is the apiculotis. So these are the main parts in the oral cavity and the palate. This is the specimen of tongue. The tongue and behind the tongue this is the apiculotis.
This is the dorsal surface of the tongue which is divided into two parts. This is the anterior two third part or oral part. And this is the posterior one-third part or the pharyngeal part.
And then there is a posterior most part of the tongue. This is the apex of tongue. Now at the junction of anterior two-third and posterior one-third, there is a V-shaped sulcus. This is known as the sulcus terminalis. And in the midline where the two limbs of the V Meet, there is a foramen cecum.
Just in front of sulcus terminalis, we can see large papilla, known as a circumvallate papilla, which are the largest papilla. In addition to these, we can see in the anterior two-third of tongue, foliate papilla, filiform and fungiform papilla scattered over the dorsum of the anterior two-third of tongue. Whereas in the posterior one-third of the tongue, We can see large aggregation of lymphoid follicles. This is known as a lingual tonsil. Now there is a fold of mucosa in the median plane between the tongue and epiglottis.
So this is known as the median glossoepiglottic fold. On each side these are the lateral folds. Glosso-epiglottic folds and this depression between median and lateral glosso-epiglottic fold is known as valacula and lateral to the lateral glosso-epiglottic fold we can see here the piriform fossa on each side of the inlet of larynx.
Now we must know the lymphatic drainage of the tongue. The tip of the tongue drains bilaterally into submandibular group of lymph nodes. The remaining part of the anterior two-third of the tongue right and left drain unilaterally into submandibular group of lymph node.
The posterior one-third of the tongue drain into the jugular omohide group of lymph nodes.