Oral Cavity and Pharynx

1. Oral Cavity and Pharynx Hannah Lea M. David

2. Anatomy of the Lips and Oral Cavity

3. Oral Vestibule • bounded externally by the lips and cheeks and internally by the alveolar processes and teeth

5. Lips • Longer upper lip, shorter lower lip • Connected by the Labial commisures(corners) • Separated from the cheek by the nasolabial fold • Orbicularisoris- muscular foundation of the lips • Blood supply: Superior and inferior labial arteries (from the Facial artery) • Drained by the facial vein, which communicates with the orbital vein via the angular vein

6. Lips • Lymphatic drainage- submandibular and submental lymph nodes • Innervation: upper lip-infraorbital nerve; lower lip- mental nerve

7. Cheeks • Lateral boundaries of the oral vestibule • Buccinator- muscular framework, innervated by the facial nerve • Buccal fat pad- between the buccinator muscle and masseter • Excretory duct of the parotid gland- runs through the buccinator muscle and opens into the mucosa of the cheek opposite the upper second molar

8. Masticator muscles • Masseter • Temporalis muscle • Medial and Lateral pterygoid muscles • Supplied by the mandibular nerve (3rd div of the trigeminal nerve)

10. Teeth • Deciduous teeth, permanent teeth • 8 per maxilla/ mandible:2 incisors,1 canine, 2 premolars, 3 molars

12. Oral Cavity • Anterior and lateral: alveolar ridge and teeth • Superiorly: Hard and soft palate • Posteriorly: faucial isthmus

13. Palate • Hard palate- palatine process of the maxilla anteriorly, incisive bone, horizontal plates of the palatine bone posteriorly.\ • Soft palate- posterior; palatal muscles (tensor velipalatini, levatorvelipalatini, palatoglossus muscle) • Mucosa: contains numerous salivary glands (palatine glands) • Sensory innervation (mucosa): Greater and lesser palatine nerves • Blood supply: ascending palatine branch of the facial artery

14. Tongue • Mylohyoid muscle- muscular foundation • Sublingual folds and sublingual papillae- undersurface of the tongue on both sides of the frenulum • Apex, body, base • Terminal sulcus-: V-shaped groove which separates the body from the base

16. Tongue • Mucosa- numerous papillae (filiform, fungiform, vallate, foliate) • Blood supply (tongue and oral floor): Lingual and sublingual artery • Drainage: facial vein to the IJV • Lymphatic drainage: ipsilat and contralatsubmandibular and submental LN • Motor innervation: Hypoglossal nerve • Sensory innervation (terminal sulcus): lingual nerve, (base) glossopharyngeal and superior laryngeal nerve

17. Diseases of the Lips and Oral Cavity

18. Cleft Lip and Palate • Epidemiology: 1 in 500, one of the most common malformation • Classification: • Cleft lip and alveolar ridge • Cleft lip, alveolar ridge, and palate and isolated cleft palate • Symptoms: hypernasal speech (due to incomplete closure of the nasopharynx), recurrent middle ear effusions and inflammatioons, septal deviations

20. Pathogenesis: developmental anomaly of the embryonic head (genetic, viral infections, placental oxygen deficiency, intrauterine bleeding, exposure to ionizing radiation) • Diagnosis should include palaption of the hard palate • Tx: surgery

21. Dermoid cyst of the oral floor • Presents with submental swelling, tense bulging of the entire anterior and lateral oral floor • DDx: Dysgenetic salivary gland cyst • May also involve the tongue and mandible

22. Transverse facial cleft • Failure of the fusion of the maxillary and mandibular processes or failure of the buccal membrane to regress due to fusion of the myoblasts • Bilateral extension of the oral fissure • Aassociated with facial dysplasia and auricular dystropia

23. Inflammations of the Lips and Oral Cavity Herpes simplex Virus • Usually HSV type 1 • MOT: Contact or droplet infection • Symptoms: Primary infection- childhood, herpetic gingivostomatitis ( bullae/vesicles on the oral mucosa preceded by fever and lethargy accompanied by regional lymphadenitis) Reactivation- in response to physical exertion, fever, Uv radiation, stress, pregnancy, herpes labialism

24. SOP: Perioral region • Dx: History, clinical exam, Tzanck smear • Complications: secondary bacterial superinfection by Staphylococcus aureus (Herpes impetiginatus), ExudativeErythemamultiforme, Pospischill- Feyrteraphthoid, herpetic meningoenecephalitis • Tx: acyclovir

25. Varicella Zoster Virus • Chickenpox(primary), Zoster (reinfection) • Symptoms: Chickenpox- papulovesicular lesions esp on the head and trunk. Zoster- segmental distribution associated with neuropathic pain • Tx: acyclovir/ famciclovir

26. Herpangina • Causes: Group a coxsackie virus, Group B CV, Retrovirus, Echovirus • Symptoms: Fever, malaise, headache, muscle pain, bullous eruptions surrounded by red halo on the oral mucosa particularly on the anterior faucial pillars, uvula and palatine tonsils • DDx: Gingivostomatitis • Tx: Symptomatic

27. Recurrent aphthousstomatitis • Inflammatory shallow ulcers with slightly raised erythematous borders • Tx: Symptomatic

28. Oral hairy leukoplakia • Pathognomonic of HIV infection • Believed to be caused by EBV • Patchy, whitish, slightly raised lesions predominantly on the border of the tongue • Painless • Tx: topical Vit A and/or podophyllin

29. Oral floor Abscess • Usu. originates from the lower molars, mucosal injuries in the oral floor • Edematous expansion with a firm erythematous swelling in the submental to submandibular areas • Difficulty swallowing and speaking • High fever • May progress to ARDS or mediastinitis • Dx: US, CT to define the extent • Tx: Incision and drainage, antibiotic treatment

30. Candidiasis • Impaired immune sytem • Whitish, firmly adherent plaques that can be scraped from the mucosa, leaving an erythematous bleeding surface • Tx: Nystatin solution or amphotericin B lozenges

31. Lesions of the tongue • Hunter’s glossitis- atrophic inflammatory condition of the tongue base, acconpanying feature of PA, s/s: burning of the tongue, dry mouth, altered sense of taste, smooth shiny appearance of the tongue with partial atrophy of the filiform papillae • Fissured tongue- numerous furrows on the dorsal surface, maybe a sign of Melkersson-Rosenthal Synd • Angioedema- swelling of the face, lips, tongue and laryynx due to a pronounced vascular reaction usu in anaphylactic or anaphylactoid reactions

32. Geographic tongue- areas of desquamation of the filiform papillae on the dorsal surface with occ burning sensation • Black hairy tongue- hyperkeratosis of the filiform papillae due to failuure of desquamation of the cornified layers

33. ATROPHIC GLOSSITIS FISSURED TONGUE ANGIOEDEMA GEOGRAPHIC TONGUE BLACK HAIRY TONGUE

34. Benign Tumors • Epithelial or mesenchymal • Papilloma, pleomorphic adenoma, fibroma, lipoma, rhabdomyomas, leiomyomas, chondromas • Tx: surgical

35. Precancerous Lesions • Leukoplakia- asymptomatic, associated with denture pressure or alcohol/nicotine abuse, always investigated by biopsy, tx: complete surgical removal • Bowen’s disease- chronic inflam disease caused by intraepidermalcarcinomam

36. Malignant tumors (Lips) • Squamous cell carcinoma – usually affects the lower lip, associated with pipe smoking and sun exposure • Intractable ulcerations in the vermillion border of the lips or large exophytic lesions, tx: surgical removal • Basal cell Ca- involves the vermillion border of the lip only by secondary spread

37. Malignant Tumors (Oral cavity) • Squamous cell Ca- smoking and alcohol abuse, presents with painful swallowing, blood tinged saliva, fetid breath odor, or asymptomatic

38. Pharynx

39. Pharynx • Tubular, fibromuscular space extending from the skull base to the inlet of the esophagus • Consists of: nasopharynx, oropharynx, hypopharynx

40. Nasopharynx • Highest part of the pharynx • From the bony skull bbase to an imaginary horizontal line at the level of the velum • Communicates with the nasal cavity via the choanae and middle ear via the orifice of the eustachian tube • (S) floor of the sphenoid sinus and pharyngeal roof , (P) first cervical vertebra

41. Oropharynx • Communicates with oral cavity via the faucial isthmus • Extends inferiorly from the lowest border of the nasopharynx to the upper margin of the epiglottis • (A) tongue base, (P) C2, C3, (L) faucial pillars

42. Hypopharynx • Lowest segment • From the superior border of the epiglottis to the inf border of the cricoidcatilage • (P) C3-C6, (A) back of the larynx