Salivary Glands and Saliva

Presented by-Dr Arpita Dutta

CONTENTSSalivary Glands SalivaINTRODUCTIONDEFINITIONCLASSIFICATIONEMBRYOLOGYDEVELOPMENTHISTOLOGYANATOMYNEURAL REGULATIONSALIVA FORMATIONSALIVARY GLAND PATHOLOGYIMAGING MODALITIESCONCLUSIONREFERENCES

INTRODUCTION COMPOSITION PROPERTIES OF SALIVA PROSTHODONTIC

CONSIDERATIONS SALIVA AS A DIAGNOSTIC TOOL METHODS OF COLLECTION OF

SALIVA CONCLUSION REFERENCES

DEFINITION Salivary Glands-

The salivary glands are group of compound exocrine glands secreting saliva. -Orban’s Oral Histology & Embryology, 14th Edition

CLASSIFICATION

SALIVARY GLANDS BASED ON ANATOMY

MAJOR SALIVARY GLANDS• PAROTID GLAND• SUBLINGUAL GLAND• SUBMANDIBULAR GLAND

MINOR SALIVARY GLANDS• LABIAL AND BUCCAL GLANDS• GLOSSOPALATINE GLANDS• PALATINE GLANDS• LINGUAL GLANDS• -BLANDIN &NUHN• -VON EBNER’S GLAND• CARMALT’S GLANDS

SALIVARY GLANDS BASED ON SECRETION

SEROUS

MUCOUS

MIXED

(Orbans Oral Histology & Embryology, 14th edtn)

PAROTID GLAND•PURELY SEROUS

SUBLINGUAL GLAND• MIXED (mainly MUCOUS)

SUBMANDIBULAR GLAND• MIXED (mainly SEROUS)

LABIAL AND BUCCAL GLANDS

• MIXED

GLOSSOPHARYNGEAL AND PALATINE GLANDS

• MUCOUS

LINGUAL GLANDS

• MIXED

VON EBNER’S GLAND’S

. SEROUS

(Orbans Oral Histology & Embryology, 14th Edition

EMBRYOLOGY

Time of origin Gland Location Intra uterine lifeParotid gland Corners of the stomodeum as placode 6th week I.U

Submandibular gland Floor of the mouth End of 6 th week I.U

Sublingual gland Lateral to S.m.primordium 8th week I.U

Minor salivary glands Buccal Epithelium 12 th week I.U

Maturity of secretory end piece: During last 2 months of gestation.

David T. Wong Salivary Diagnostics, Wiley-Blackwell

David T. Wong Salivary Diagnostics, Wiley-Blackwell

DEVELOPMENTBUD FORMATION CORD FORMATION

BRANCHING OF CORDS

LOBULE FORMATIONCANALIZATION

CYTODIFFERENTIATION

(Orbans Oral Histology & Embryology, 13th edtn)

STAGES OF DEVELOPMENT-

•BUD FORMATION•CORD FORMATION•BRANCHING OF CORDS•LOBULE FORMATION•CANALIZATION•CYTODIFFERENTIATION

PAROTID GLANDParotid gland:-Largest salivary gland

-20-25% of total saliva.

-Pyramidal in shape.

-Weighs around 20-30g.

-Superficial portion of gland is located subcutaneously, in front of the external ear & deeper portion lies behind ramus of mandible.

-4 surfaces: superior, superficial, anteromedial, posteromedial

-3 borders- anterior, medial, posterior

-Associated with facial nerve (pes anserinus)

Stenson’s duct: -35- 40mm long

Runs forward across masseter muscle, turns inwards at the anterior border of masseter

Runs through the 3Bs-Buccal pad of fatBuccopharyngeal fasciaBuccinator Muscle

- opens at a papilla opposite the second maxillary molar.

Arterial supply-External carotid artery

Venous drainage-External jugular vein

Lymphatic drainage-Upper deep cervical lymph nodes.

Nerve supply: Greater auricular and Auriculotemporal nerve

Sympathetic- From the sympathetic plexus around the external carotid artery

Parasympathetic

SUBMANDIBULAR GLAND10 to 15 gm. Size of a Walnut

65-70% of total saliva.

Located at Posterior portion of floor of mouth, medial aspect of mandible & wrapping around posterior border of mylohyoid.

3 surfaces-Inferior, Medial, LateralThe post. Border of mylohyoid divides the gland:

Superficial lobe : situated in the digastric triangle wedged between body of mandible and

mylohyoid

Small deep lobe: lying in the floor of the mouth between mylohyoid and the hyoglossus muscle

on the lateral aspect of the tongue

RELATIONS OF THE SUBMANDIBULAR GLAND

SUBMANDIBULAR DUCT•Wharton's duct runs forward and opens into the mouth beneath the tongue,

lateral to lingual frenum i.e sublingual caruncle.

•40mm

Blood supply: Facial and lingual arteries. Veins correspond to arteries, drain into internal Jugular Vein

Lymphatic drainage: Submandibular lymph node & jugulodigastric nodes.

Nerve supply:•Parasympathetic supply: Facial nerve reaching gland through the lingual nerve & submandibular ganglion.

• Sympathetic Supply:Postganglionic fibers from plexus on facial artery

SUBLINGUAL GLAND

Smallest major salivary gland Weighs- 2gm.

2.5% of total saliva.

Located at anterior part of floor of the mouth, just between mucosa & mylohyoid muscle.

Saliva is poured into a series of small ducts (duct of Rivinus) and open through large duct- Bartholin’s duct, that opens with submandibular duct at the caruncula sublingualis.

Essentials of Medical Physiology, Sembulingam 4th Edition

Blood supply: Sublingual & submental arteries.

Lymphatic drainage: Submental lymph nodes

Nerve supply:

Parasympathetic supply: Facial nerve reaching gland through the lingual nerve & submandibular ganglion.

Sympathetic Supply: -Postganglionic fibers from plexus on facial artery.

MINOR SALIVARY GLANDS Labial and buccal glands- Lips and cheek

Glossopalatine- isthmus in glossopalatine fold

Palatine glands- lamina propria of the posterolateral region of hard palate

submucosa of the soft palate and the uvula

Lingual–• Anteriorlingual GLANDS OF BLANDIN AND NUHN -apex of the

tongue

• Posterior Lingual (mucous)- lateral and posterior to the vallate papilla

• Posterior lingual( serous) VON EBNER’S GLANDS- between the

muscle fibers of the tongue below the vallate papilla.

HISTOLOGY

ACINI- TERMINAL SECRETORY UNIT.

LEADING INTO DUCTS

OPEN TO ORAL CAVITY AND SECRETION TO ANATOMIC

LOCATION

SEROUS CELLS MUCOUS CELLS

DUCTAL SYSTEM

MYOEPITHELIAL CELLSBASKET CELLS

.

stellate or spider like cellsflattened nucleussurrounded by -

• small amount of perinuclear cytoplasm

• long branching process that embracing the secretory duct cells.

CONNECTIVE TISSUE

•Same as connective tissue in other parts of body

•Contain macrophages, plasma cells, fibroblasts, macrophages, mast cells

•Extension of connective tissue into septa lobulates the gland

serous salivary gland

serous acini, zymogen granules

intercalated ducts and striated ducts

interlobular ducts with stratified epithelium.

lobules with connective tissue septa.

nearby lymph node with capsule.

PAROTID GLAND HISTOLOGY

.mixed salivary gland

predominantly serous acini; some mucous acini with serous demilunes

short intercalated ducts.

striated ducts with simple cuboidal lining epithelium.

interlobular ducts with stratified cuboidal or stratified columnar epithelium surrounded by connective tissue.

PAROTID GLAND HISTOLOGYPAROTID GLAND HISTOLOGYSUBMANDIBULAR GLAND HISTOLOGY

.mixed salivary gland

predominantly mucous acini; some serous demilunes.

acini are composed of centrally-located mucous cells and peripheral serous demilunes.

short intercalated ducts.

striated ducts with simple columnar lining epithelium

interlobular ducts with stratified cuboidal/columnar epithelium, surrounded by connective tissue.

SUBLINGUAL GLAND HISTOLOGY

PHYSIOLOGICAL FACTORS AFFECTING SALIVATION

TASTE OF EATABLES

SURFACE OF OBJECT

DEHYDRATIONAGE

EMOTIONS AND PSYCHOLOGICAL

EFFECTS

INCREASED SALIVATION

DECREASED SALIVATION

Syllabus of Complete Dentures, Charles M. Heartwell and Arthur O. Rahn, 4th edtn

PHASE OF SALIVATION

• SMELLS• VIEW

CEPHALIC

Syllabus of Complete Dentures, Charles M. Heartwell and Arthur O. Rahn, 4th edtn

FORMATION OF SALIVA• TWO STAGE MODEL of saliva secretion

Physiology, Robert M. Berne and Matthew N. Levy, 3rd edth

NEURAL REGULATION OF SALIVARY SECRETION

PATHOLOGIES OF SALIVARY GLANDSDEVELOPMENTAL

DISORDERS• ABERRANT GLANDS• APLASIA AND HYPERPLASIA• ATRESIA

OBSTRUCTIVE DISORDERS

• SIALOLITHIASIS• MUCOCELE• NECROTIZING SIALOMETAPLASIA

NEOPLASTIC DISORDERS

• BENIGN• MALIGNANT

• SJOGREN’S SYNDROME• RADIATION• XEROSTOMIA

INFLAMMATORY DISORDERS

• VIRAL• BACTERIAL

Textbook of Oral Medicine, A.V.Ghom, 3rd edtn

DEGENERATIVE CONDITION- SJOGREN’S SYNDROME

• A.k.a Gougerot Sjogren’s Syndrome/ Sicca Syndome

• It is an autoimmune disorder described as a triad of : -Keratoconjuctivitis sicca -Xerostomia -Rheumatoid arthritis

Two types: -Primary -Secondary

Keratoconjunctivitis sicca

Xerostomi

a

Rheumato

id arthri

tis

Sjogren’s syndrom

e

Clinical freatures:•Dry mouth and dry eyes

•Dry and fissured tongue

•Primary sjogren’s syndrome are associated with parotid gland enlargment, purpura, lymphadenopathy.

Treatment: 1. Ocular lubricants and salivary

substitutes,2. maintenance of oral hygiene3. Frequent fluoride application,4. sialogogues.

Fig- DRY AND FISSURED TONGUE

SALIVARY GLAND IMAGING MODALITIES

1. PLAIN FILM RADIOGRAPHY• OCCLUSAL VIEW• ORTHOPANTOGRAPH• LATERAL OBLIQUE• POSTERIOR ANTERIOR SKULL PROJECTION 2. SIALOGRAPHY

3. ULTRASONOGRAPHY

4. SCINTIGRAPHY

5. COMPUTED TOMOGRAPHY

6. MAGNETIC RESONANCE IMAGINGFig:- MANDIBULAR OCCLUAL VIEW OF A CALCIFIED STONE IN THE WHARTON’S DUCT

SCINTIGRAPHY

AXIAL CT

SIALOGRAPHY

SIALOGRAPHY• Retrograde injection of a iodinated

contrast agent into the ductal system of a salivary gland.

• Oldest imaging modality.

• First sialogram performed by CARPY 1904 on an isolated parotid using mercury as a contrast agent.

• Simple, quick and painless procedure

AMAMENTARIUMSialography cathetersLacrimal probesIodinated contrast agentCotton rolls

Maxillofacial Imaging, Angelo. M DelBalso

CONTRAST AGENTS

INJECTION TECHNIQUES

HYDROSTATIC INJECTION

DISTENTION INJECTION

HAND INJECTION

FAT SOLUBLE

•ETHIODOL•LIPIODOL•PANTOPAQUE

WATER SOLUBLE

•ANGIOGRAPHIC DYES•SINOGRAFIN

PHASES OF SIALOGRAPHY

DUCTAL PHASE ACINAR PHASE EVACUATION AND POST-EVACUATION PHASE

Maxillofacial Imaging, Angelo. M DelBalso

Saliva

INTRODUCTIONSaliva is a viscous, transparent liquid secreted by cells of the salivary glands.

Salivary flow facilitates-1. Speech2. Mastication3. Food Bolus Formation And Its

Swallowing4. General Oral Health And

Function.

It plays a critical role in retention of dentures due to its lubricating function and, thus, dry mucosa often leads to compromise in the retention of prosthesis.

DEFINITION “Saliva is clean, tasteless, odourless, slightly acidic viscous fluid,

consisting of secretions from the parotid, sublingual, submandibular salivary glands and the mucous glands of the oral cavity.” - Stedmans medical dictionary 26th edition

• Saliva is a clear, alkaline, somewhat viscid secretion from the parotid, submandibular, sublingual & smaller mucous glands of the mouth. – Dorland Medical dictionary

• Saliva is a complex fluid produced by the salivary glands , the most important function of which is to maintain the well being of the oral cavity . – Tencate’s Book of Oral Histology

WHOLE / TOTAL SALIVA

FLOW RATE(ML/MIN)

WHOLE SALIVA PAROTID GLAND SALIVA SUBLINGUAL GLAND AND SUBMANDIBULAR GLAND SALIVA

RESTING STATE 0.2-0.4 0.04 0.1

STIMULATED STATE

2.0-5.0 1.0-2.0 0.8

pH 6.7-7.4 6.0-7.8 6.0-7.4

Ten Cate’s Oral Histology, Development, Structure, and Function, Seventh Edition

COMPOSITION

WATER-99.5%

SOLID -0.5%

SOLID COMPOSITION OF SALIVA

ORGANIC• SECRETORY PROTEINS:• ENZYMES AMYLASE,RIBONUCLEASE,KALLIKREIN ESTERASE,CYSTATIN,PEROXIDE LYSOZYMES,LACTOFERRIN ACID PHOSPHATASE PROLINE RICH PROTEINS GLYCOPROTIENS• IMMUNOGLOBULINS IgG, IgM, IgA• BLOOD CLOTTING FACTORS• DESQUAMATED EPITHELIAL CELLS• MICROORGANISMS PRODUCTS• LEUKOCYTES• SERUM REMNANTS

INORGANIC

• ELECTROLYTES SODIUM POTASSIUM CALCIUM CHLORINE BICARBONATE PHOSPHATE MAGNESIUM SULPHATE IRON IODINE

FUNCTIONS

ANTI BACTERIAL• LYSOZYMES+LACTOFERRIN+LACTOPERO

XIDASE+IMMUNOGLOBULINS+CYSTATINS

ANTIFUNGAL • IMMUNOGLOBULINS+CHROMOGRAINS

ANTI VIRAL • CYSTATINS+MUCINS+IMMUNOGLOBULINS+SECRETORY LEUKOCYTE

BUFFER• BICARBON

ATE• PHOSPHA

TE• PROTEINS

PROTECTION AGAINST DEMINERALIZATION• MUCINS• CALCIUM• PHOSPHATE

LUBRICATION

GLYCOPROTEINS

MUCINS

REMINERALIZATIONSTATHERIN

PHOSPHATECALICUM

Bolus formationMUCINS+WATER

Taste of eatablesGUSTIN+WATER

Digestion of foodAMYLASE+PROTEASE+LIPASE

PROPERTIES

• Total amount : 1,200 – 1500 ml in 24 hrs. A large proportion of this volume is secreted at meal time, when the secretory rate is highest.

• Consistency : slightly cloudy, due to presence of cells and mucin.

• pH : usually slightly acidic (ph 6.35 – 6.85)

• Specific gravity : 1.002 – 1.012

• Freezing point : 0.07 – 0.340c.

Total volume secreted 1200ml to 1500ml/day

PAROTID GLAND

SUBLINGUAL GLANDMINOR GLANDS

SUBMANDIBULAR GLAND

20%

7- 8% <10%

65-70%

Saliva composition and functions: A comprehensive Review, The Journal of Contemporary Dental Practice vol(9),no 3,2008

FACTORS AFFECTING COMPOSITION OF SALIVA

Time of the day

Source of secretion

Pathology

Flow rate

Differential gland contribution

Circadian rhythm

Nature of stimuli

Diet and hydration

David T. Wong Salivary Diagnostics, Wiley-Blackwell

SALIVA: A DIAGNOSTIC TOOL

SALIVA

BACTERIA

VIRUSES

NEOPLASTIC

CONDITIONS

SYSTEMIC DISEASE

BIOMARKERS

DRUG ABUSE

CONDITIONS

David T. Wong Salivary Diagnostics, Wiley-Blackwell

Salivary testing is becoming more common as clinicians have begun to appreciate its

advantages & investigators defined its worth. Saliva proves to be a reflection of

the body.

SYSTEMIC DISEASES-

• HEREDITARY DISEASES- CYSTIC FIBROSIS

• AUTOIMMUNE DISEASES- SJOGREN’S SYNDROME

• MALIGNANCIES- ADENOCARCINOMA, BREAST CARCINOMA, OVARIAN

CANCER (MARKERS)

VIRAL INFECTION MARKERS-

• HIV

• OTHER VIRAL DISEASES (due to immunoglobulins present in saliva)

SALIVA AS A DIAGNOSTIC TOOL

DRUG MONITORING-• THERAPEUTIC- Carbamazepine, Diazepam, Ethosuximide,

Lithium, Tolbutamide, etc• RECREATIONAL- Nicotine, Cocaine, Barbiturates,

Benzodiapines, Marijuana, etc

MONITORING OF HORMONE LEVELS

DIAGNOSIS OF ORAL CONDITIONS ASSOCIATED WITH DEEPER SYSTEMIC CONDITIONS

• Forensic odontology- serological and cellular analysis of saliva aids in identification of accused

-Saxena S, Kumar S. Saliva in forensic odontology: A comprehensive update. J Oral Maxillofac Pathol [serial online] 2015 [cited 2016 Apr 24];19:263-5.

• Salivary pH assessment using telemetry:

Device called telemetry system is incorporated in the denture which has a radiosensitive diode, oscillator, ph sensor, and a computer analyzer

METHODS OF COLLECTION OF SALIVA

• Draining method- funnel placed near lip and patient asked to expectorate saliva into the funnel to collect in a pre-weighed test tube

• Spitting method- saliva allowed to accumulate in the floor of the mouth and then spat into a pre-weighed tube. For stimulated saliva patient is asked to chew on paraffin.

• Suction method- saliva is aspirated into a pre-weighed container using a saliva ejector.

• Absorbent method- preweighed swab, cotton roll, gauze sponge.

APPLICATION IN PROSTHODONTICS

62

• Adhesion• Cohesion • Surface Tension• Capillary Attraction• Atmospheric

Pressure• Viscosity of Saliva

ROLE OF SALIVA IN COMPLETE DENTURE RETENTION

Adhesion: It is achieved through ionic forces between charged salivary glycoproteins and surface epithelium or acrylic resin.

According to Bernard Levin– the most adhesive saliva is thin but containing some mucous component

Cohesion: It is a retentive force because it occurs within the layer of fluid (saliva) that is present between the denture base and the mucosa and works to maintain the integrity of the interposed fluid.

Interfacial force/ Surface tension• It is the resistance to separation of two

parallel surfaces that is imparted by a film of liquid between them.

• It is dependent on the ability of the fluid to ‘ wet’ the rigid surrounding material (WETTABILITY).

Capillary Action

• Capillarity is what causes a liquid to rise in capillary tube

• • When adaptation of denture base to mucosa on

which it rests is sufficiently close, the space filled with thin film of saliva acts like capillary tube in that liquid ,seeks to increase contact with both denture and mucosal surface.

Atmospheric pressure

•The cohesive forces result in the formation of a concave meniscus at the surface of the saliva in the border region of the denture.

•When a fluid film is bounded by a concave meniscus the pressure within the fluid is less than that of the surrounding medium;

•Thus a pressure differential will exist between saliva film and air and thereby aids in the retention of the denture

XEROSTOMIA AND HYPERSALIVATIONXEROSTOMIA• Dry mouth/ pasties/ cotton mouth• Hyposalivation or Aptyalism

Causes-• Dehydration or Renal Failure• Sjogren’s Syndrome• Radiotherapy• Trauma to Salivary gland or duct• Drugs• Smoking of marijuana/cannabis• Shock

HYPERSALIVATION• Excess saliva secretion• Physiological- Pregnancy• Pathological is called Ptyalism,

Sialorrhea, Sialosis

Causes-• Decay of tooth or a neoplasm• Disease of foregut, stomach or

intestine• Cerebral Palsy• Parkinsonism

DID YOU KNOW?In ancient China, a suspect would be made to chew dry rice while being questioned. When the suspect spat out the rice, they were assumed to be guilty if the grains remained stuck to their tongue. The reason was that the stress caused slow saliva flow and induced a dry mouth (activation of the sympathetic nervous system).

PROSTHODONTIC MANAGEMENT OF PATIENT WITH XEROSTOMIA

In dry environment, fixed non tissue bearing prosthesis are preferred where indicated

FPDs should have full coverage retainers and easily cleaned pontics and connectors

Margins of retainers should be supragingival

Health of residual teeth and periodontal tissues

Use of gingivally approching clasp avoided

Tooth supported denture with minimal tissue coverage

Metal denture bases are preferred

FIXED PARTIAL DENTURE PROSTHESIS

REMOVABLE PARTIAL DENTURE PROSTHESIS

Procedures -aim at optimizing retention and stability

Use dentures with metal bases

Use of soft liners to improve comfort

Use of denture adhesives to augment retention

Frequent recall – As more prone to candidal infections

COMPLETE DENTURE PROSTHESIS

TREATMENT OPTIONS

•Use of sialogogues•Saliva reservoirs•Flexible dentures

SALIVA RESERVOIS

Pattanaik B, Pattanaik S. Prosthetic rehabilitation of a xerostomia patient with a mandibular split salivary reservoir denture. Annals and Essences of dentistry 2010;3:32–5

SPLIT DENTURES

Mendoza AR, Tomlinson MJ. The split denture: a new technique for artificial saliva reservoirs in mandibular dentures. Aust Dent J 2003;48:190–4

Flexible denturesSaliva substitutes are contraindicated in • asthma• iritis• Glaucoma

limitations of the split dentures • Require adequate vertical dimension• Structure weakened• repair and relining are difficult• Too bulky

Flexible dentures-• Long lasting• do not warp or become brittle• exhibit better accuracy• softer material locks into the undercuts of the ridges

thereby adapting to the constant movement• Can retain a small percentage of water- more

compatibility and softer than acrylic

• Dental restorations are affected by saliva. They have ability to dissolve silicates.

• Changes physical properties of various impression materials.

• Causes electro-galvanisation between silver and gold discolors the restoration, causes pain.

• Hampers clinicians view and contaminates working area.

ISOLATION:

METHODS OF FLUID CONTROL

SALIVA EJECTORS RUBBER DAMSVEDOPTER

ANTI-SIALOGOGUES RETRACTION CORDS GAUZE AND COTTON ROLLS

IMPLANTS

• Failure of Implants is seen due to microbiota present in saliva.

• Bacterial species from human saliva may penetrate along the implant-abutment interface

• Essentials of Human Anatomy- Head and Neck, 4th Edition- A K Datta• Orbans Oral Histology & Embryology, 14th Edition• David T. Wong Salivary Diagnostics, Wiley-Blackwell• Ten Cate’s Oral Histology, Development, Structure, and Function, Seventh Edition• Oral Radiology Principles And Interpretation Sixth Edition,Stuart C. White and

Michael J. Pharoah• Textbook of Oral Medicine, A.V.Ghom, Third Edition• Physiology, Robert M. Berne and Matthew N. Levy, Third Edition• Syllabus of Complete Dentures, Charles M. Heartwell and Arthur O. Rahn, Fourth

Edition• A contemporary review of the factors involved in complete denture retention,

stability, and support. Part I: retention. Jacobson TE, Krol AJ. J Prosthet Dent. 1983 Jan;49(1):5-15.

REFERENCES

•Essentials Of Medical Physiology K. Sembulingam 4th Edition

•Syllabus of Complete Dentures, Charles M. Heartwell and Arthur O. Rahn, 4th edtn

• Ten Cate’s Oral Histology, Development, Structure, and Function, Seventh Edition

•Mendoza AR, Tomlinson MJ. The split denture: a new technique for artificial saliva reservoirs in mandibular dentures. Aust Dent J 2003;48:190–4

•Pattanaik B, Pattanaik S. Prosthetic rehabilitation of a xerostomia patient with a mandibular split salivary reservoir denture. Annals and Essences of dentistry 2010;3:32–5

•Saliva composition and functions: A comprehensive Review, The Journal of Contemporary Dental Practice vol(9),no 3,2008

•Kaufman E, Lamster IB. The diagnostic applications of saliva--a review. Crit Rev Oral Biol Med. 2002;13(2):197-212.

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