ORAL CAVITY, And Salivary glands Dr. Abuelnor

Objectives: Describe the anatomy the oral cavity, (boundaries, parts, nerve supply).  Describe the anatomy of the palate, (parts, muscles, nerve & blood supply).  Describe the anatomy of the tongue, (structure, muscles, motor and sensory nerve supply, blood supply, and drainage).  Describe the anatomy of the parotid gland: position, shape, structures within it, innervation and parotid duct.  Describe the anatomy of the submandibular and sublingual salivary glands: location,shape, parts, ducts and innervation of the glands. اسم ورقم المقرر – Course Name and No. 5/8/2019

The Mouth The mouth extends from the lips to the oropharyngeal isthmus It is subdivided into: Vestibule: which lies between the lips and cheeks externally and the gums and teeth internally Mouth cavity proper, which lies within the alveolar arches, gums and teeth

Mouth Proper It has a roof, formed by hard palate and soft palate The floor is formed the mylohyoid muscle . On each side the gums and teeth

Nerve Supply The roof is supplied by the greater palatine and nasopalatine nerves, nerve fibers travel in the maxillary nerve The floor is supplied by the lingual nerve, a branch of mandibular nerve The cheek is supplied by the buccal nerve, a branch of mandibular nerve

Tongue Mass of striated muscles covered with the mucous membrane Divided into right and left halves by a median septum Three parts: Oral (anterior ⅔) Pharyngeal (posterior ⅓) Root (base) Two surfaces: Dorsal Ventral

Mucous Membrane of Tongue The mucous membrane of upper surface of the tongue can be divided into anterior and posterior parts by a V- shaped sulcus called sulcus terminalis The apex of the sulcus is marked by a small pit called foramen cecum The foramen cecum marks the site of the upper end of thyroglossal duct

Papillae of the Tongue papillae are present on the upper surface of the anterior two thirds of the tongue. Posterior third of the tongue is devoid of papillae but has a nodular irregular surface caused by underlying lingual tonsils

Mucous Membrane of Tongue The mucous membrane on the inferior surface of the tongue is smooth It is reflected from the tongue to the floor of the mouth. Frenulum of the tongue attaches the tongue to the floor of the mouth in the midline

Muscles of the Tongue Muscles of the tongue are intrinsic and extrinsic Intrinsic muscles are confined to the tongue and are not attached to bone They consist of longitudinal, transverse and vertical fibers They are supplied by hypoglossal nerve They alter the shape of the tongue

Extrinsic Muscles of the Tongue They are attached to the bone and the soft palate These are: The genioglossus, The hyoglossus, The styloglossus, and The palatoglossus

Blood Supply of Tongue The tongue is supplied by: The lingual artery The tonsillar branch of the facial artery The ascending pharyngeal artery The veins drain into the internal jugular vein

Lymph Drainage of Tongue The tip of the tongue drains into the submental lymph nodes The remainder of the anterior two thirds of the tongue drains into the submandibular and deep cervical lymph nodes on both sides From posterior third drains into the deep cervical lymph nodes on both sides

The Palate The palate forms the roof of the mouth It is divided into: Hard palate infront Soft palate behind

Hard Palate Hard palate is formed by the palatine processes of the maxillae and the horizontal plates of the palatine bones Soft palate is a mobile fold attached to the posterior border of the hard palate Its free posterior border presents in midline a conical projection called uvula

Muscles of Soft Palate Muscles of the soft palate are: Tensor veli palatini Levator veli palatini Palatoglossus Palatopharyngeus Musculus uvulae

Nerve Supply of the Palate The greater and lesser palatine nerves from the trigeminal nerve The nasopalatine nerve, branch of a maxillary nerve The glossopharyngeal nerve also supplies the soft palate

Blood Supply of the Palate The greater palatine branch of maxillary artery The ascending palatine branch of facial artery The ascending pharyngeal artery Lymph drains into deep cervical lymph nodes

Parotid produces a serous, watery secretion. Salivary glands are exocrine glands, that produce saliva. There are 3 large named pairs of salivary glands and multiple minute unnamed glands in the submucosa of the oral cavity Parotid produces a serous, watery secretion. Submandibular produces a mixed serous & mucous secretion. Sublingual secretes saliva that is predominantly mucous in character. ndibular

PAROTID GLAND Largest salivary gland. Formed entirely of serous acini. Position: located between mandibular ,and Mastoid process Shape: triangular the apex behind angle of the mandible Base directed upward just below the zygomatic arch, external auditory meatus Accessory part: A small part that is separated from the main gland. اسم ورقم المقرر – Course Name and No. 5/8/2019

Parotid Duct It opens into the vestibule of the mouth on a small papilla, opposite the upper second molar (maxillary) tooth.

From superficial to deep 1- Facial nerve: What are the Structures within the Parotid gland? From superficial to deep 1- Facial nerve: It is the most superficial structure, it divides the gland into superficial & deep parts. 2- Retromandibular vein: intermediate in position Formed by the union of maxillary & superficial temporal veins. 3- External carotid artery: Most deep, It is divided into maxillary and superficial temporal arteries. اسم ورقم المقرر – Course Name and No. 5/8/2019

The postganglionic fibers running in auriculotemporal nerve. Nerve Supply: Parasympathetic from inferior salivary nucleus – tympanic nerve- through the glossopharyngeal nerve to tympanic plexus- lesser petrosal to otic ganglion- The postganglionic fibers running in auriculotemporal nerve. Sympathetic: from plexus around external carotid artery. اسم ورقم المقرر – Course Name and No. 5/8/2019

Blood supply Arterial: ECA & its branches. Venous drainage: retromandibular vein. Lymphatic: parotid & deep cervical lymph nodes. اسم ورقم المقرر – Course Name and No. 5/8/2019

SUBMANDIBULAR SALIVARY GLAND Located deep to the body of the mandible Formed of 2 parts: Large superficial part Small deep part

SUBMANDIBULAR DUCT The duct emerges from the deep part of the gland. It passes forward along the side of the tongue, under the mucous membrane of the floor of the mouth. It is crossed laterally by the lingual nerve It opens on the summit of a small sublingual papilla, which lies at the side of the frenulum of the tongue.

SUBMANDIBULAR DUCT Clinically, it is important to remember that the submandibular duct can be palpated through the floor of the mouth alongside the tongue. Saliva can usually be seen emerging from the orifice of the duct.

SUBLINGUAL GLAND The smallest of the three salivary glands. It lies below the mucous membrane of the floor of mouth, close to the midline.

Sublingual ducts The sublingual ducts are 8 to 20 in number. Most open into the summit of the sublingual fold, but a few may open into the submandibular duct.

Blood Supply Arterial supply: Facial artery. Venous drainage: Facial vein. Lymph drainage: Submandibular lymph nodes. اسم ورقم المقرر – Course Name and No. 5/8/2019

NERVE SUPPLY Parasympathetic secretomotor supply is from superior salivary nucleus of the facial (7th) nerve. The fibers pass to the submandibular ganglion via the chorda tympani nerve and the lingual nerve. Postganglionic parasympathetic fibers reach the submandibular & sublingual glands either directly or along the duct.

References: Gray's Anatomy for Students- Second edition. Clinically Oriented Anatomy , Keith L. Moore- Sixth edition. Netter’s Clinical Anatomy, Second edition.