Nonneoplastic pathology
1. Metabolic conditions
2. Infectious conditions
3. Immunologic conditions
Neoplastic pathology
Postoperative complications
Parotid Gland
Largest of the major salivary glands (28 g)
Located inferior to zygomatic arch,
anterior to the mastoid process and
external auditory meatus and posterior to
the ramus
Stensen's duct is approximately 6 cm in
length and penetrates the buccinator
muscle and exits opposite the second
molar
The facial nerve divides the parotid gland
into superficial and deep lobes
Submandibular Gland
Located in the anterior part of the
submandibular triangle
Wharton's duct also is approximately
6 cm long penetrates the mylohyoid
and enters the mouth at the lingual
frenulum
Sublingual Gland
The almond-shaped sublingual gland is
the smallest of major salivary glands (2.0
g)It is located in the sublingual space
The numerous Rivinus' ducts or plica
enter the floor of the mouth separately
Occasionally, these multiple short ducts
form a larger sublingual duct, which
opens into the submandibular duct
Minor Salivary Glands
There are approximately 1,000 minor
salivary glands located in the
mucosa of the lips, cheeks, hard and
soft palate, uvula, floor of mouth,
posterior part of the tongue,
retromolar area, peritonsillar region,
trachea, and lacrimal system.
Function of Salivary Glands
The chief function of this network of major
and minor salivary glands and ducts is to
maintain the fluid homeostasis of the oral
cavity.
The serous-mucous fluid (ie, saliva)
hydrolyzes starches to maltose.
Lubrication of the mucosa, teeth, and
tongue facilitates clear, understandable
speech.
Function of Salivary Glands
Approximately 1,500 mL of saliva are
produced every 24 hours
• 90% of the total quantity produced by
the parotid and submandibular glands
• 5% by the sublingual glands
• 5% by the remaining minor glands
Diagnosis of Salivary Gland
Disorders
Diagnosis of salivary gland disorders
is based on presenting signs and
symptoms, preexisting diseases, and
physical examination.
• plain-film radiography and sialography
to assist with diagnosis of
nonneoplastic pathology
• CT and MRI to delineate the size and
extent of salivary neoplasms
Non-neoplastic Disorders
• Reactive conditions
• mucoceles and ranulas
• irradiation reactions
• sialolithiasis
• necrotizing sialometaplasia
• Infectious
• Nutrition disorders
• Medication reactions
• Immunologic disorders
Mucoceles
Most common reactive condition of
the minor salivary glands
Mucoceles form when trauma to
excretory ducts of the minor glands
allows the spillage of mucus into the
surrounding connective tissue
formation of painless, smoothsurfaced,
bluish lesions
Mucoceles
The lower lip is the most frequent
site followed by the buccal mucosa,
the ventral surface of the tongue, the
floor of the mouth, and the
retromolar region
Treatment:
• observation
• surgical excision
Ranulas
The result of blocked sublingual gland
ducts
Ranulas are unilateral, soft-tissue lesions,
often with a bluish appearance.
They vary in size and may cross the
midline of the mouth and cause deviation
of the tongue
A mucosal extravasation that herniates
the mylohyoid muscle is called a
"plunging" ranula
Treatment of a Ranula
Surgical excision of the involved gland
and marsupialization
• Marsupialization: suturing its walls to
an adjacent structure, leaving the
packed cavity to close by granulation
Irradiation Reaction
A common side effect of tumoricidal
doses of ionizing radiation is xerostomia
Frequent sips of water and frequent mouth
care are the most effective interventions
for xerostomia
Saliva substitutes (eg, mixed solutions of
methylcellulose, glycerin, and saline) or
pilocarpine hydrochloride may help these
symptoms
Sialolithiasis
Salivary gland calculi form when the
• glands are inactive
• metabolic conditions that promote salt
precipitation in the glands.
• Dehydration and poor oral hygiene also are
predisposing factors for salivary gland calculi
Calculi may cause partial or total
occlusion of the major salivary gland
ducts
Sialolithiasis
Middle-aged patients most frequently
affected
85% of all salivary stones are located in
the submandibular gland
Patients with sialolithiasis typically
complain of recurrent episodes of pain
and swelling when the gland is stimulated
to secrete, as when chewing food
Sialolithiasis
Treatment
excision of salivary calculi from
Wharton's duct (ie, sialolithotomy) and
the administration of antibiotics for
underlying salivary gland infections
and/or
excision of the entire submandibular
gland
Necrotizing Sialometaplasia
Usually involves minor salivary glands
Occurs secondary to vascular infarct due
to
smoking, trauma, DM, vascular disease,
L/A
Age range 23-66 yrs
1-4 cm ulceration
resembles mucoepidermoid carcinoma
and SCCA clinically and histologically
Usually heal in 6-10 weeks
Nutrition Disorders
Nutrition disorders such as pellagra (ie,
niacin deficiency), kwashiorkor (ie, protein
deficiency), beriberi (ie, thiamine
deficiency), and vitamin A deficiency are
associated with parotid gland enlargement
Malabsorption syndromes (eg, parasitic
and protozoan infections, amebic
dysentery, celiac sprue) also can cause
malnutrition and result in salivary gland
dysfunction
Medication Reactions
Many medications (eg, amitriptyline,
imipramine, nortriptyline, atropine,
phenothiazine derivatives,
antihistamines) decrease salivary
flow and cause parotid enlargement
Metabolic Conditions
Patients with alcoholic cirrhosis often
experience asymptomatic enlargements of
their parotid glands, which are attributed
to chronic protein deficiency
Diabetes mellitus and hyperlipidemia
cause fatty infiltrations that replace the
functional parenchyma of the salivary
glands and decrease the flow of saliva
Infectious Conditions
Mumps
Cytomegalovirus (CMV), which is a
DNA, ether-sensitive virus of the
herpes family that is transmitted by
human contact.
Bacterial infections
acute and recurrent chronic sialadenitis
Etiology: Staphylococcus aureus,
Staphylococcus pyogenes, Streptococcus
pneumoniae, and Escherichia coli
Predisposing factor: reduction in salivary
flow (ie, secondary to dehydration,
debilitation, medication side effects)
Treatment is directed at elimination of the
causative agent, rehydration of the
patient, and surgical drainage of
purulence when indicated
Immunologic conditions
HIV may manifest with parotid gland
enlargement and parotid
lymphadenopathy often are observed in
these immunocompromised patients.
Parotid gland enlargement may be caused
by benign lymphoepithelial lesions in the
gland, hypertrophied periparotid lymph
nodes, or secondary infections from CMV
Sjogren's syndrome
Autoimmune disorder characterized
by a chronic inflammatory reaction of
exocrine glands +/or systemic
connective tissues
Sjogren's syndrome includes any of
the three findings:
1. keratoconjunctivitis sicca (ie, dry eyes)
2. salivary gland enlargement, and xerostomia
3. vasculitis
4. purpura
5. hepatosplenomegally
6. obstructive pulmonary disease
7. anemia
8. rheumatoid arthritis
Neoplasms
Salivary neoplasms generally present as
painless, slow-growing masses
Neoplasms of the major salivary glands
usually are benign
Neoplasms of the minor salivary glands
usually are malignant
Rapidly expanding salivary neoplasms
that are associated with pain and neural
dysfunction are more likely to be
malignant
Neoplasms
85% of salivary neoplasms arise in
the parotid
10% in the submandibular gland
5% in the minor salivary glands
Salivary neoplasms rarely occur in
the sublingual glands
Benign salivary neoplasms
Histologically, benign neoplasms are
classified as:
pleomorphic adenomas / benign mixed
tumors
1. papillary cystadenolymphomas
2. /Warthin's tumors
3. oncocytomas
4. monomorphic adenomas
5. benign lymphoepithelial lesions
Benign salivary neoplasms
The most common benign neoplasm is pleomorphic adenoma
parotid gland 92.5%
submandibular gland 6.5%
The treatment of choice for benign
neoplasms is surgical excision
Malignant salivary neoplasms
Malignant salivary neoplasms are classified
as:
1. malignant mixed tumors
2. mucoepidermoid carcinoma
3. adenocarcinoma
4. acinic cell carcinoma
5. squamous cell carcinoma
6. adenoid cystic carcinoma
7. metastatic melanoma and SCCA
Malignant salivary neoplasms
Surgery is the treatment of choice for
resectable malignant salivary neoplasms
Surgeons also may perform neck
dissections if lymph node involvement is
present or suspected
Postoperative radiation therapy may be
used as an adjunctive treatment to
eradicate microscopic or residual disease
Complications
Xerostomia
Hemorrhage
Temporary facial nerve paralysis 15%
Long-term facial nerve paralysis
Frey's syndrome
Salivary Gland Disorders
Clinicians are frequently confronted
with the necessity of assessing and
managing salivary gland disorders
This basic knowledge of salivary
gland anatomy, physiology,
pathophysiology is necessary to
treat your patients properly
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