Salivary Glands Major salivary glands: Lie at some distance from the mucosa and communicate with one or more ducts. Three paired masses of the parotid, submandibular, and sublingual glands. Minor Salivary glands: Lie in the mucosa or submucosa and open directly or indirectly via many short excretory ducts. 12/5/2018

Salivary Glands Function: Lubrication of food, assisting swallowing. Moistening of the buccal mucosa, essential for speech. Provision of an aqueous solvent, necessary for taste. Provision of a fluid seal, necessary for sucking. Secretion of digestive enzymes, amylase. Secretion of hormones, Glucagons-like protein and ? serotonin 12/5/2018

Salivary Glands The Parotid gland: The Parotid gland: The largest of the salivary and is predominantly serous with few scattered mucous acini. It lies below the external auditory meatus in a deep hollow between the ramus, the mastoid and the styloid process. 12/5/2018

Salivary Glands: The Parotid gland: It is roughly wedge shape, with an upper and lower poles with the base above and the apex below behind the angle of the mandible. It is also wedge shaped in the horizontal plan with three surfaces, lateral, antero-medial and postero-medial, the base is the lateral and apex lies against the pharyngeal wall 12/5/2018

Salivary Glands: The Parotid gland: The parotid sheath is a tough capsule, derived from the investing layer of the deep cervical fascia Superficial layer is attached to the zygomatic arch The deep part to the styloid process, the mandible (stylo-mandibular ligament) and the tympanic part of temporal bone 12/5/2018

Salivary Glands: The Parotid gland: The upper pole adhere to the cartilage of external auditory and the TMJ capsule The lower pole is rounded and lie below and behind the angle of the mandible. The facial nerve divide it into superficial and deep parts or lobes 12/5/2018

Salivary Glands: The Parotid gland: Lateral surface is flat and covered with skin and superficial fascia containing great auricular nerve. Lymph nodes lie within the substance or under the sheath. The duct and the five branches of the facial nerve emerge from its anterior border 12/5/2018

Salivary Glands: Anteromedial surface The Parotid gland: U-shaped clasping the posterior border of the ramus with masseter laterally and medial pterygoid medially and inferiorly, separated by the stylomandibular ligament from the submandibular salivary gland 12/5/2018

Salivary Glands: The Parotid gland: The posteromedial surface Indented by the mastoid process and its muscles Lie against the styloid process with its three muscles and two ligaments The accessory gland Lies on the masseter between the duct and the zygomatic arch 12/5/2018

Salivary Glands: Parotid gland The Parotid duct Emerge from the convex anterior border of the superficial part and pass anteriorly over the masseter muscle. At the anterior border of the muscle it turn medial and pierce the buccal pad fat and buccinator muscle, pass for a short distance under the mucous membrane before it opens opposite the upper second molar 12/5/2018

Salivary Glands: Facial nerve: Parotid gland Structures within the gland: Facial nerve: enter the gland from the deep surface and emerge from behind the anterior border. Retromandibular vein: Deep to the branches of the nerve 12/5/2018

Salivary Glands Parotid gland The capsule: Derived from the deep cervical fascia which split at the lower pole to encase the gland The deep layer pass beneath the gland and ie attached to the skull base Part is inserted to styloid process and angle of mandible is thickened, stylomandibular ligament separating the gland from the submandibular one The superficial layer pass anterior on the masseter muscle and is attached to the lower border of the zygomatic arch Tight insertion will lead to sever pain on inflammation and swelling of parotid 12/5/2018

Salivary Glands: External carotid artery : Parotid gland External carotid artery : With its two terminal branches it is the deepest structure Periauricular lymph nodes: Lies within the gland or under the capsule 12/5/2018

Salivary Glands: Parotid gland Blood supply Nerve supply: External carotid artery and retomandibular vein Nerve supply: Secretomotor fibres from the inferior salivary nucleus to the glossopharyngeal nerve, tympanic branch, tympanic plexus, lesser superficial petrosal to otic ganglion, to the Auriculotemporal nerve Sympathetic fibres From the superior cervical plexus Vasoconstrictor Sensory fibres Gland, auriculotemporal Capsule, greater auricular (C2) 12/5/2018

Salivary Glands: Parotid gland The capsule send septa to the interior of the gland separating it into lobules and making surgical removal difficult. Submandibular gland is loosely enveloped and can be shelled out easily Medially, the capsule is closely related to the pharynx and the great vessels in the carotid sheath Break through by tumour or sharp instrument 12/5/2018