Sublingual salivary glandDr. Ganesh MengalIII MDS

IntroductionThe oral cavity is kept moist by a film of fluid called saliva, this complex salivary fluid is secreted by the salivary gland which is exocrine in nature . Salivas important function is to maintain the well being of mouth hence any Individuals with a deficiency of salivary secretion experience difficulty eating, speaking, swallowing and prone to mucosal infections .

Types of salivary glandsI Based on anatomic locationParotid glandSub mandibular glandSub lingual glandAccessory glands (labial, lingual, palatal buccal,glossopalatine and retromolar)

III Based on size and amount of secretion Major salivary glands Minor salivary glands II Based on type of secretion

Serous:parotid ,submandibular and von ebners glands

Mucous : sub lingual,labial ,buccal,palatine ,glossopalatine,posterir part of tongue

Mixed:sub mandibular, sub lingual ,anterio labial buccal and lingual minor glands

Embryology Development :individual salivary glands arise as a proliferation of oral epithelial cells,forming focal thickening that grows into underlying ectomesenchyme

Parotid : 6 th week of I U : corners of stomatidium

Sub mandibular : end of 6 th week of I U : floor of mouth

Sub lingual : 8 th week of I U: lateral to primordium

Minor salivary gland : 12 th week of I U :buccal epithelium

Sub lingual salivary glandMixed gland ,predominantly mucous secretion.Smallest of major salivary glandThis gland lies just beneath the mucous membrane of the floor of the mouth ,in contact with the sub lingual fossa on the lingual aspect of mandible.Bartholins duct, through which this gland communicates oral cavity .This duct may open into wartons duct or directly in oral cavity with a sub lingual papilla

Relations : Anteriorly : The gland of the opposite side. Posteriorly : The deep part of the submandibular gland.Medially : The genioglossus muscle, the lingual nerve, and the submandibular duct. Laterally : The gland is related laterally to the sublingual fossa of the medial surface of the mandible.Superiorly : The mucous membrane of the floor of the mouth, which is elevated by the gland to form the sublingual fold. Inferiorly : The gland is supported by the mylohyoid muscle. Sublingual ducts : The sublingual ducts are eight to twenty in number. The majority open into the mouth on the summit of the sublingual fold, but a few may open into the submandibular duct.

Nerve supply:Parasympathetic secretomotor supply from the superior salivary nucleus of the seventh cranial nerve. The nerve fibers pass to the submandibular ganglion via the chorda tympani nerve and the lingual nerve. Postganglionic parasympathetic fibers pass to the gland via the lingual nerve. Postganglionic sympathetic fibers reach the gland as a plexus of nerves around the facial and lingual arteries.

Nerve supply

Blood supply:The gland is supplied by branches of the facial and lingual arteries. The veins drain into the facial and lingual veins.

Lymph Drainage:The lymph vessels drain into the submandibular and the deep cervical lymph nodes.

Architecture of the glandSalivary gland consist of secretory end pieces that are composed of serous cells ,mucous cells , or mucous end pieces capped by serous demilunes and a system of ducts (intercalated,striated and excretory)that modify the saliva produced by the end pieces and convey to the oral cavity.contractile myoepithelial cells are distributed around the end pieces and intercalated ducts. The gland is supported by the connective tissue ,which carries the nerve ,vascular and lymphatic supply.

Composition of salivaVolume : 600 1000ml/dayElectrolytes :Na+ ,K+ ,HCO3- ,Ca++ ,Mg++ , SCN- and FSecretory proteins :amylase,proline rich protiens ,mucins ,histatin,peroxidase lysosyme,lactoferrinsecretory immunoglobulins ;IgG and IgMSmall organic molecules :Glucose ,amino acids urea,uric acid and lipids Others : insulin,cyclic adenosine monophpsohate binding proteins and serum albumin

Rate of flowFlow rate(ml/min) whole parotid submandibular

Resting 0.2-0.4 0.04 0.1

Stimulated 2.0-5.0 1.0-2.0 0.8

pH 6.7-7.4 6.0-7.8

Functions ProtectionBufferingTooth integrityAnti microbial activityTissue repairDigestionTasteAids in denture retention

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