Pathology of the Oral Cavity

1. Pathology of the Oral Cavity

2. Diseases of the Oral Cavity • To learn: • Disorders of the Oral Mucosa and Gingiva • Disorders of the Salivary glands • Disorders of the Teeth and Jaw bones • Disorders due to the Systemic Diseases

3. Disorders of the Oral Mucosa and Gingiva • Ulcerative and inflammatory lesions • Aphtous ulcers • Herpes virus infections • Fungal infections • Hyperkeratotic lesions • Leukoplakia • Erythroplakia • Tumors • Benign tumors • Malignant tumors

4. Ulcerative and inflammatory lesions Aphtous ulcers • Extremely common superficial ulcerations (erosions) of the oral mucosa • Painful • Single or multiple • Shallow • Hyperemic (erythematous) or yellowish-gray • Less than 5 mm in diameter • Covered by a thin exudate and rimmed by a narrow zone of erythema

6. Location: • Soft palate • Buccolabial mucosa • Floor of the mouth • Lateral borders of the tongue

7. Triggers or Etiology: • Inflammatory bowel diseases • Behçet’s disease • Hypersensitivity reactions • Emotional stress • Endocrine influences (pregnancy, menstruation) • Autoimmune reactions (involving both cellular and humoral mechanisms) • Infectious diseases

8. Herpes virus infections • Orofacial herpetic infections are caused by HSV type 1 (HHV-1) • HHV-2 most often involves the genital tract • Most primary oral infections with HSV-1 are trivial “cold sores” • Adults harbor latent HHV-1: • upper respiratory tract infections • excessive exposure to cold, wind, or sunlight • allergic reactions

10. Herpetic gingivostomatitis • Generally acute • Common in AIDS patients • In severe cases  • keratoconjunctivitis • encephalitis • Lesions: • the oral and pharyngeal mucosa • the tongue • the gingivae

11. Herpes simplex Herpetic gingivostomatitis (HIV-positive patient)

13. Fungal infections Candida albicans • Superficial, curdy, gray to white inflammatory membrane • Fibrinosuppurative exudate + C.albicanswith an underlying erythematous inflammatory base • Risk factors: • diabetes mellitus • neutropenia • immune deficiency syndromes • AIDS • antibiotic therapy

14. Oral trush

15. Candida albicans

17. Hyperkeratotic lesions Leukoplakia(white plaque) • White plaque on the oral mucous membranes that cannot be removed by scraping • Precancerous lesion • Range from completely benign epithelial thickenings to highly atypical lesions with dysplastic changes that merge with carcinoma in situ (CIS) • Etiology: • Tobacco • smoking (cigar, cigarette, pipe) • Chewing tobaco • Alcohol • Chronic irritations (i.e. cheek bite)

18. Leukoplakia

19. Erythroplakia (dysplastic leukoplakia) • Red, velvety, possibly eroded area • Higher risk of malignant transformation • more than 50% • Etiology: • Tobacco (cigarettes, pipes, cigars, and particularly chewing tobacco ) • alcohol • Chronic exposure to persistent irritants • ill-fitting dentures • hot meals • HPV

20. Erythroplakia

21. Tumors Benign tumors and tumor-like conditions • Tumors • Papilloma (HPV serotypes 6 and 11) • Angioma (hemangioma & lymphangioma) • Tumor-like conditions • Fordyce spots (ectopic sebaceous glands) • Mucocele (minor salivary glands – destruction of ductus)

24. Malignant tumors Squamous cell carcinoma: 95% of cancers of the oral cavity and the tongue • The small residual includes • adenocarcinoma (of salivary gland origin) • melanoma • various carcinomas

25. Squamous cell carcinoma (Epidermoid carcinoma) • Location (most predicted): • Lower lip • Floor of the mouth • Tongue (lateral borders) • Etiology: • Leukoplakia and erythroplakia • Tobacco : alcohol&smoking, tobacco chewing • Ill-fitting dentures • Jagged teeth • HPV • Sunlight (lower lip) • Chronic infections

26. Morphology • In the early stage: • Raised, firm, pearly plaques • irregular - roughened • verrucose areas of mucosal thickening • Differential diagnosis : leukoplakia & erythroplakia • As these lesions enlarge: • protruding masses • undergo central necrosis • irregular, shaggy ulcer rimmed by elevated, firm, rolled borders

28. Microscopy • with leukoplakia and erythroplakia • well-differentiated keratinizing neoplasms • or anaplastic • or sometimes undifferentiated (sarcomatoid) tumors • Metastases: • regional and mediastinal lymph nodes • lungs • liver • bones

29. Squamous cell carcinoma

30. Disorders of the Salivary glands Inflammatory disorders • Sialadenitis • Sjögren syndrome • Mikulicz syndrome Tumors • Benign tumors • Plemorphic adenoma • Warthin tumor • Malignant tumors • Mucoepidermoid carcinoma • Adenoid cystic carcinoma

31. Inflammatory Disorders of the Salivary glands • Viral (mumps) • Bacterial (complication of sialolithiasis) • Autoimmune origin • Sjögren’s syndrome: • involvement of the salivary glands  xerostomia (dry mouth) • involvement lacrimal glands  keratoconjunctivitis sicca (dry eyes) • Sarcoidosis : • bilateral sarcoidosis of the parotid, submaxillary, and sublingual glands • uvea involvement

32. Sjögren’s syndrome Mikulicz syndrome

33. Tumors of the Salivary glands Benign tumors Plemorphic adenoma • Mostly parotid gland • Painless swelling at the angle of the jaw • Excision; may recur (10%)

34. Microscopy • Composed of epithelial elements and myoepithelial cells dispersed throughout a matrix of • mucoid, • myxoid, • chondroid tissue  a mixed tumor

36. Warthin Tumor(Papillary Cystadenoma Lymphomatosum) • Almost always in the parotid gland • Small, round to oval, encapsulated mass • Excision; may recur (10%) • Microscopy: • (1) spaces are lined by a double layer of epithelial cells • (2) dense lymphoid stroma sometimes forming germinal centers

37. Malignant tumors Mucoepidermoid carcinoma • Particularly the minor salivary glands • Radiation-induced neoplasm • Mixture of squamous cells, mucus-secreting cells • May recur ( 30%) • Disseminate to distant sites (30%) Adenoid cystic carcinoma • Particularly the minor salivary glands • Frank pain due to neural invasion • Microscopy: round-cystic spaces filled by mucus

38. Tumors of the Salivary glands

39. Disorders of the Teeth and Jaw bones • Teeth • Caries • Inflammation (pulpitis, apical granuloma & cyst) • Jaw bones • Fractures • Inflammation (osteomyelitis) • Cysts (odontogenic; non-odontogenic) • Tumors • Soft tissues • Bone & Cartilage • Odontogenic

41. Odontogeic cysts & tumors

42. Disorders due to the Systemic Diseases INFECTIOUS DISEASES • Measles: Koplik’s spots • Infectious mononucleosis: acute tonsillitis/pharyngitis, cervical lymphadenopathy • Diphtheria: pseudomembrane (tonsils/retropharynx) • AIDS: Herpesvirus infection (gingivostomatitis), Candida albicans, Kaposi sarcoma

43. DERMATOLOGIC DISORDERS • Lichen planus: reticulate, white (keratotic) lesions • Pemphigus: vesicles and erosions • Bullous pemphigoid: bullae and erosions • Erythema multiforme (Stevens-Johnson syndrome): maculopapular-vesiculobullous lesions • follows an infection • drug • cancer • auto-immune disorder

44. Pemphigus vulgaris

45. HEMATOLOGIC DISORDERS • Pancytopenia and/or Leukemia • gingivitis • pharyngitis • tonsillitis • neck cellulitis (Ludwig’s angina) • Monocytic leukemia • gingival infiltration

46. MISCELLANEOUS • Melanotic pigmentation: • Albright’s syndrome • Peutz-Jegher’s syndrome • Dilantin (phenytoin): gingival hyperplasia • Pregnancy: granuloma gravidarum • Other Syndromes: oral manifestations can be found in the hereditary or acquired syndromes • Teeth anomalies • Macroglossia • Bifid palate/tongue/lip • Hemangiomas, ect.

47. Peutz-Jegher’s syndrome; Gingival hyperplasia