s-g

advertisement
Salivary gland diseases
5th Class
Oral Medicine
Lec 6
Dr. Jamal al dewan
BDS , Diploma (oral diagnosis),MSc (oral
med.)
Saliva
is a watery substance formed in the mouths of animals,
secreted by the salivary glands. Human saliva comprises
99.5% mostly water, plus electrolytes, mucus,
white blood cells, epithelial cells (which can be used to
extract
DNA),
glycoproteins,
enzymes
(such
as amylase and lipase), antimicrobial agents such as
secretory IgA and lysozyme.
The enzymes found in saliva are essential in beginning
the process of digestion of dietary starches and fats.
The amount of saliva that is produced in a healthy person per
day; estimates range from 0.75 to 1.5 litres per day while it is
generally accepted that during sleep the amount drops to
nearly zero.
In humans, the submandibular gland contributes around 70–
75% of secretion, while the parotid gland secretes about 20–
25% and small amounts are secreted from the other salivary
glands.
Functions of saliva ????
• Parotid
saliva is pure serous and secreted
through Stensen’s ducts, the orifices of
which are visible on the buccal mucosa in
the vicinity of the maxillary first or
second molar.
• Submandibular gland
saliva is mix of mucous and serous
types and secreted through the
submandibular
duct (Wharton’s duct), which exits at
side of the lingual frenulum.
• sublingual gland
saliva is primarily mucous and may enter the
floor of the mouth directly
via the short, independent ducts of Rivinus.
One or more of these ductules may converge
to form the major duct also known as
Bartholin’s duct, which opens into or near the
submandibular duct.
Investigations for salivary glands
1-Sialometry:
is the collection and measurement of the
amount of saliva produced in a certain
time.
2-Sialochemistry:
examination of the composition of the
saliva like electrolytes and enzymes.
3- Imaging
• Plain Film Radiography like panoramic or lateral
oblique and occlusal projections.
• Ultrasonography
• CT scan and MRI.
• Sialography: using iodine containing contrast media
which introduced through the salivary gland duct
followed by multiple x-ray views.
• Scintigraphy:
by
using
radioactive
isotopes(Technetium ) to demonstrate the salivary
gland function and to determine abnormalities in
gland uptake and excretion.
Sialoliths
(also termed salivary calculi or salivary
stones)
• typically calcified masses that form within the
secretory system of the major salivary glands.
• composed of organic and inorganic substances
including calcium and phosphates, cellular
debris, glycoproteins, and
mucopolysaccharides.
• Although the exact mechanism of sialolith
formation has not been proven but there are
etiologic factors favoring salivary stone formation
• irregularities in the duct system,
• local inflammation,
• dehydration,
• medications such as anticholinergics and diuretics
• calcium saturation
The higher rate of sialolith formation in
the submandibular gland is due to
• (1) the torturous course of Wharton’s
duct,
• (2) the higher calcium and phosphate
levels of the secretion
• (3) the increased mucoid nature of the
secretion
Clinical Presentation
• Patients with sialoliths most commonly present
with a history of acute, periprandial pain and
intermittent swelling of the affected major
salivary gland.
• If there is concurrent infection, there may be
expressible suppurative or nonsuppurative
drainage and erythema or warmth in the
overlying skin. The patient may complain from
systemic manifestations such as fever
Treatment
• During the acute phase of sialolithiasis,
therapy is primarily supportive.
• Stones at or near the orifice of the duct
can often be removed by milking the
gland, but deeper stones require
intervention with conventional surgery.
Mucocele
• Mucocele is a clinical term that describes
swelling caused by the accumulation of saliva
at the site of a traumatized or obstructed
minor salivary gland duct.
• Mucoceles can be classified histologically as
extravasation types or retention types.
Clinical Presentation
• Mucoceles often present as discrete, painless,
smooth-surfaced swellings that can range from a
few millimeters to a few centimeters in diameter.
Superficial lesions frequently have a characteristic
blue hue.
• Deeper lesions can be more diffuse, covered by
normal-appearing mucosa.
• The lesions vary in size over time; and frequently
traumatized, causing them to drain and deflate.
• Extravasation mucoceles most frequently
occur on the lower lip, followed by
buccal mucosa, tongue, floor of the
mouth, and retromolar region while
mucous retention cysts are more
commonly found on the upper lip, palate,
buccal mucosa, floor of the mouth
Treatment
• Conventional definitive surgical treatment of
mucoceles involves removal of the entire
lesion along with the feeder salivary glands
and duct.
• Alternative treatments that have been
explored with varying degrees of success
include cryosurgery and laser surgery.
Ranula
• A form of mucocele located in the floor of the
mouth is known as a Ranulas are believed to
arise from the sublingual gland usually
following mechanical trauma to its ducts of
Rivinus, resulting in extravasation of saliva.
• Other possible causes include an obstructed
salivary duct or a ductal aneurysm.
Clinical Presentation
• It is presented as painless, slow-growing, fluctuant,
movable mass located in the floor of the mouth.
• Usually, the lesion forms to one side of the lingual
frenulum; however, if the lesion extends deep into the soft
tissue, it can cross the midline.
• The superficial ranulas can have a typical bluish hue, but
when the lesion is deeply seated, the overlying mucosa
may have a normal appearance. The size of
• the lesions can vary, and larger lesions can cause deviation
of the tongue. In a “plunging” ranula, the swelling may
observed extraorally.
treatment
• The most predictable method of
eradicating both oral and plunging
ranulas is to remove the associated
sublingual gland because this will
almost certainly eliminate
recurrences
Necrotizing Sialometaplasia
• Necrotizing sialometaplasia is a benign, selflimiting, reactive inflammatory disorder of
salivary tissue.
• Clinically and histopathologically, NS can
resemble a malignancy and its misdiagnosis has
resulted in unnecessary radical surgery.
• The etiology is unknown, although it likely
represents a local ischemic event, infectious
process, or perhaps an immune response to an
unknown allergen.
• Development of NS has been associated
with:
• smoking
• trauma
• denture wear
• surgical procedures.
Clinical Presentation
• The incidence of NS appears to be higher in male
patients and especially in those older than 40
years
• Most commonly it presents as a painful, rapidly
progressing swelling usually unilateral of the hard
palate with central ulceration and peripheral
erythema.
• Numbness or\ anesthesia in the associated area
may be an early finding.
• The lesions are typically of rapid onset and range
in size from 1 to 3 cm.
Diagnosis
• Histopathologic diagnosis is
warranted to rule out a malignant
process, biopsy specimens should be
submitted to a pathologist with
extensive training in oral and
maxillofacial pathology.
Treatment
• NS is considered a self-limiting
condition typically resolving within
3–12 weeks.
• During this time, supportive and
symptomatic treatment is usually
adequate.
Download
Related flashcards
Create Flashcards