Introduction to the Salivary Glands Dennis E. Lopatin, Ph.D Dept. of Biologic & Materials Sciences

Even Science Fiction Has Discovered the Importance of Saliva!

Saliva in Oral Health: Protective Functions Lubrication Lubrication Mucins, proline-rich glycoproteins, water Mucins, proline-rich glycoproteins, water Antimicrobial Antimicrobial Amylase, complement, defensins, lysozyme, lactoferrin, lactoperoxidase, mucins, cystatins, proline-rich glycoproteins, secretory IgA, secretory leukocyte protease inhibitor, statherin, thrombospondin Amylase, complement, defensins, lysozyme, lactoferrin, lactoperoxidase, mucins, cystatins, proline-rich glycoproteins, secretory IgA, secretory leukocyte protease inhibitor, statherin, thrombospondin

Saliva in Oral Health: Protective Functions (cont’d) Growth Factors Growth Factors Epidermal growth factor (EGF), transforming growth factor-alpha (TGF-  ), transforming growth factor- alpha (TGF-  ), fibroblast growth factor (FGF), insulin-like growth factor (IGF-I & IGF-II), nerve growth factor (NGF) Epidermal growth factor (EGF), transforming growth factor-alpha (TGF-  ), transforming growth factor- alpha (TGF-  ), fibroblast growth factor (FGF), insulin-like growth factor (IGF-I & IGF-II), nerve growth factor (NGF) Mucosal Integrity Mucosal Integrity Mucins, electrolytes, water Mucins, electrolytes, water

Saliva in Oral Health: Protective Functions (cont’d) Lavage/cleansing Lavage/cleansing Water Water Buffering Buffering Bicarbonate, phosphate ions, proteins Bicarbonate, phosphate ions, proteins Remineralization Remineralization Calcium, phosphate, statherin, anionic proline- rich proteins Calcium, phosphate, statherin, anionic proline- rich proteins

Saliva in Oral Health: Food and Speech-related functions Food Preparation Food Preparation Water, mucins Water, mucins Digestion Digestion Amylases, lipase, ribonuclease, proteases, water mucins Amylases, lipase, ribonuclease, proteases, water mucins Taste Taste Water, gustin Water, gustin Speech Speech Water, mucins Water, mucins

Salivary Gland Anatomy Parotid Gland Parotid Gland Submandibular Gland Submandibular Gland Sublingual Gland Sublingual Gland Minor Glands Minor Glands

Major Salivary Glands Parotid Glands Submandibular Glands

Structure of the Ducts

Salivary Constituents Water & electrolytes Water & electrolytes Proteins Proteins Non-electrolytes Non-electrolytes Non-glandular proteins Non-glandular proteins

Components of Whole Saliva Salivary glands Salivary glands Water, proteins, electrolytes, small organic molecules Water, proteins, electrolytes, small organic molecules Blood and blood derivatives Blood and blood derivatives Intraoral bleeding, gingival crevicular fluid (serum & inflammatory cells) Intraoral bleeding, gingival crevicular fluid (serum & inflammatory cells) Extrinsic substances Extrinsic substances Food debris, toothpaste and mouth rinse Food debris, toothpaste and mouth rinse Other fluids Other fluids Bronchial and nasal secretions Bronchial and nasal secretions Lining cells Lining cells Epithelial keratins Epithelial keratins Microbiota Microbiota

Factors Contributing to Saliva Content Normal Human Variability Normal Human Variability Unstimulated vs. stimulated saliva Unstimulated vs. stimulated saliva Aging Aging Medications Medications Disease Disease Circadian rhythms Circadian rhythms Objective vs. subjective determinations Objective vs. subjective determinations

Human Variations Large range defines “normality” Large range defines “normality” A little goes a long way A little goes a long way Changes over time Changes over time

Normal Variations in Saliva Output

Unstimulated vs. Stimulated Saliva Unstimulated Unstimulated Basal production Basal production Confers most protection Confers most protection Importance of minor and submandibular output Importance of minor and submandibular output Low output during sleeping hours Low output during sleeping hours Stimulated Stimulated Protection during mastication Protection during mastication Assists in deglutition Assists in deglutition Importance of parotid output Importance of parotid output

Circadian Rhythm

Effects of Aging on Saliva Quantity Quantity No significant changes in major secretions No significant changes in major secretions No significant changes in minor secretions No significant changes in minor secretions Quality Quality No general changes No general changes

Stimulated Parotid Flow Over Time

Assessment of Salivary Flow Objective measures (Clinical tests) Objective measures (Clinical tests) Major gland secretions Major gland secretions Minor gland secretions Minor gland secretions Whole saliva Whole saliva Subjective measures (Patient perceptions) Subjective measures (Patient perceptions) Xerostomia (Do you have a dry mouth?) Xerostomia (Do you have a dry mouth?) Questionnaires (Dry mouth, trouble swallowing?) Questionnaires (Dry mouth, trouble swallowing?) Thirst (Are you often thirsty?) Thirst (Are you often thirsty?)

Factors Affecting Salivary Production Local diseases Local diseases Systemic diseases Systemic diseases Medications Medications Head and neck radiation Head and neck radiation Chemotherapy Chemotherapy

Local Factors Affecting Saliva Obstructive Diseases Obstructive Diseases Neoplasms, mucous plugs, calculi Neoplasms, mucous plugs, calculi Inflammatory Diseases Inflammatory Diseases Acute viral sialadenitis (myxovirus of mumps) Acute viral sialadenitis (myxovirus of mumps) Acute suppurative bacterial sialadenitis Acute suppurative bacterial sialadenitis Chronic recurrent sialadenitis Chronic recurrent sialadenitis Allergic parotiditis Allergic parotiditis Head and Neck Irradiation Head and Neck Irradiation Diet Diet

Sialadenitis: Inflammation of the Salivary Gland

Bacterial Parotiditis: Inflammation of the Parotid Gland

Medications Influence Saliva Anti-cholinergics Anti-cholinergics Anti-histamines Anti-histamines Anti-depressants, antipsychotics Anti-depressants, antipsychotics Sedative and hypnotic agents Sedative and hypnotic agents Anti-hypertensives Anti-hypertensives Anti-Parkinson drugs Anti-Parkinson drugs

Oral Side-Effects of Prescribed Drugs RG Smith & AP Burtner, 1994 Xerostomia - Dry mouth Dysgeusia - Impairment of taste Stomatitis - Inflammation of oral mucous membranes Glossitis - Inflammation of tongue

Systemic Diseases That Influence Saliva Sjögren’s syndrome Sjögren’s syndrome Sarcoidosis (a systemic granulomatous disease, especially of lungs, but affecting many other organs, including parotid glands) Sarcoidosis (a systemic granulomatous disease, especially of lungs, but affecting many other organs, including parotid glands) Cystic fibrosis Cystic fibrosis Diabetes Diabetes Alzheimer’s disease Alzheimer’s disease AIDS AIDS Dehydration Dehydration

Submandibular Duct Obstruction 2° to Infection

Head and Neck Radiation Parotid vs. Submandibular Parotid vs. Submandibular Dysfunction is dose- and field-dependent Dysfunction is dose- and field-dependent Threshold of permanent destruction: cGy Threshold of permanent destruction: cGy

Salivary Flow Following Radiation Therapy

Chemotherapy Alters salivary constituents Alters salivary constituents Normal function returns Normal function returns Bone marrow transplantation: graft vs. host disease Bone marrow transplantation: graft vs. host disease

Salivary Dysfunction and Oral Sequelae Caries Caries Mucositis Mucositis Oral ulceration Oral ulceration Taste Taste Swallowing Swallowing Dentures Dentures Infections Infections

Salivary Dysfunction and Oral Sequelae: Caries Incipient decay Incipient decay Recurrent decay Recurrent decay Root vs. coronal decay Root vs. coronal decay

Extensive Caries in a post-radiation patient

Caries in a xerostomic individual Glossitis Mucositis Caries

Salivary Dysfunction and Oral Sequelae: Mucositis Pain Pain Infections Infections Dysphagia Dysphagia Impaired nutrition Impaired nutrition Dehydration Dehydration

Mucositis

Salivary Dysfunction and Oral Sequelae: Oral Ulceration Wound healing Wound healing Lichen planus Lichen planus Recurrent aphthous ulcers Recurrent aphthous ulcers Pain Pain Secondary infection (Candidiasis) Secondary infection (Candidiasis)

Xerostomia: Dry Fissured Tongue

Salivary Dysfunction and Oral Sequelae: Taste Reduced enjoyment of eating Reduced enjoyment of eating Altered supra-threshold and threshold performance Altered supra-threshold and threshold performance Sucrose, sodium chloride Sucrose, sodium chloride Citric acid, quinine sulfate Citric acid, quinine sulfate

Salivary Dysfunction and Oral Sequelae: Swallowing Subjective complaints of dysphagia Subjective complaints of dysphagia Increased duration in oral swallow times Increased duration in oral swallow times Dry swallows Dry swallows Wet swallows Wet swallows

Salivary Dysfunction and Oral Sequelae: Dentures Decreased retention and stability Decreased retention and stability Increased complaints Increased complaints Greater likelihood for Candida infections Greater likelihood for Candida infections

Salivary Dysfunction and Oral Sequelae: Infections Candidiasis Candidiasis Caries Caries Gingivitis Gingivitis Viral infections Viral infections Bacteremias Bacteremias Aspiration pneumonia Aspiration pneumonia

Candida 7th Week Following Tonsil Radiation Treatment

Candida/Denture Stomatitis

Saliva and Oral health: Conclusions Saliva in health Saliva in health Saliva in disease Saliva in disease Prevention of disease Prevention of disease Treatment of disease Treatment of disease

Saliva deficient