This document discusses necrotizing sialometaplasia, an uncommon condition affecting the salivary glands that is believed to be caused by ischemia and local infarction of salivary tissue. It most frequently presents as a non-ulcerated swelling or pain on the hard palate, and can develop into a crater-like ulcer. Histopathology shows acinar necrosis and squamous metaplasia of salivary ducts. While the cause is unknown, predisposing factors include trauma, dental procedures, tumors, and infections. The condition is self-limiting and typically heals without complications.

1. NECROTIZING
SIALOMETAPLASIA

2. Necrotizing Sialometaplasia
• Uncommon locally destructive
inflammatory condition of the
salivary glands.
• Cause: unknown but they believe it
is the result of ischemia of the
salivary tissue that leads to local
infaction.

3. ISCHEMIA AND LOCAL INFARCTION
LEADING TO NECROTIZING
SIALOMETAPLASIA
OXYGEN
No blood supply
No oxygen
No ATP
No glucose

4. Predisposing factors:
–Traumatic injuries
–Dental injections
–Ill fitting dentures
–Upper respiratory
infections
–Adjacent tumors
–Previous tumors
***However many cases occur without any
known predisposing factors.

5. CLINICAL FEATURES
• Most frequently develops in the
palatal salivary glands
• Hard palate > soft palate
***2/3 of palatal cases are
unilateral, with the rest being bilateral
or midline in location

6. Unilateral

7. Bilateral
Midline
in location

8. CLINICAL FEATURES
• Has also been reported in other
minor salivary gland sites and
occasionally in the parotid gland.
• Submandibular and sublingual
glands are rarely affected.

9. CLINICAL FEATURES
• Most common in adults and in men
• The condition appears initially as a
non-ulcerated swelling often
associated with pain or paresthesia
with crater-like ulcer that can range
from less than 1cm to more than
5cm in diameter appearing within 2
to 3 weeks.

10. CLINICAL FEATURES

11. HISTOPATHOLOGIC FEATURES
• Microscopic appearance of
necrotizing sialometaplasia is
characterized by acinar necrosis in
early lesions, followed by associated
squamous metaplasia of the salivary
ducts.

12. HISTOPATHOLOGIC FEATURES

13. Treatment
• The lesion is self-limiting in most
instances and heals uneventfully.

14. Xerostomia

15. Xerostomia
• Refers to subjective sensation of
a “dry mouth”
• Frequently but not always
associated with salivary gland
hypofunction.

16. Xerostomia

17. CAUSES
• DEVELOPMENTAL
-Salivary gland aplasia
• WATER OR METABOLITE LOSS impaired
fluid intake
-impaired fluid intake
-hemorrhage
-vomiting or diarrhea

18. CAUSES
• IATROGENIC
-medications
• LOCAL FACTORS
-decreased mastication
-smoking
-mouth breathing

19. CAUSES
• SYSTEMIC DISEASES
-Sjogren’s syndrome
-diabetes mellitus
-diabetes insipidus
-sarcoiadosis
-HIV infection
-Graft-versus-host disease
-psychogenic disorder