Oral Medicine #2

Notes

Salivary Gland Disease

Sialometry

unstimulated salivary flow : 0.3 - 0.4 ml/min

clinically significant xerostomia : ≤ 0.1 ml/min

drug ↑ : pilocarpine (radiation-induced xerostomia, Sjogren's syndrome)

drug ↓ : bendroflumethiazide (diuretic)

Radiology

Calculus?

• Plain radiographs
• Parotid glands - AP radiograph
• SM gland - true occlusal
• Ultrasound

Obstruction?

• Sialography

Mass?

• Ultrasound (first-line)
• CT / MRI

Abnormal function?

• Radioisotope imaging

Salivary Gland Disorders

Obstructive

• Extraductal - neoplasia, trauma
• Duct wall thickening - fibrosis → stricture, papilloma
• Intraductal - calculus

Sialadenitis

• Acute
• Viral (mumps - paramyxovirus)
• Bacterial (↓ salivary flow)
• Chronic
• Bacterial
• Relapsing - congenital duct abnormality
• Radiation
• Sclerosing (Kuttner tumor) - immune disorder
• Sarcoidosis - chronic granulomatous inflammation
• Sialosis - abnormal neurosecretory control

Sjogren's syndrome

• Primary
• Secondary + RA, SLE, progressive systemic sclerosis, primary biliary cirrhosis, renal tubular acidosis, mixed connective tissue disorder

👉 sialometry (salivary) and Schirmer test (lacrimal)

👉 autoantibodies against Ro (SS-A) and La (SS-B)

👉 labial gland biopsy → histopathological diagnosis

Salivary Gland Tumors

Benign

• Pleomorphic adenoma
• Wharthin's tumor (bilateral) = papillary cystadenoma lymphomatosum

Malignant

• Adenoid cystic carcinoma - spread along nerve
• Mucoepidermoid carcinoma
• Acinic-cell carcinoma
• Polymorphous low-grade adenocarcinoma - infiltrative but good prognosis

Salivary Gland Cysts

Mucous extravasation mucocele (most frequent) - lower labial

Mucous retention mucocele - upper labial

SM gland surgery : 

facial nerve damage → weakness of lower lip

lingual nerve damage → lingual paresthesia

Parotidectomy :

→ facial weakness

→ numbness of ear (great auricular nerve)

→ Frey's syndrome = sweating around the ear when patient eats (gustatory sweating)

→ salivary fistula

Orofacial Pain

Assessment

👉 History taking

👉 Examination : TMJ, muscles of mastication, cranial nerves

👉 TRO : cracked tooth syndrome, dentine sensitivity, pulpitis, periapical periodontitis, periodontal abscess

Disorders of TMJ

Examination

• movement - pain / obstruction / path / deviation
• palpation - pain
• auscultation - click / crepitus
• muscle tenderness - medial pterygoid cannot be examined

Radiology

• ✖ muscular parafunction
• ✖ internal disc derangements
• ✔ bony abnormality (RA / oeteoarthrosis)
• OPG
• Transcranial oblique lateral view (whole joint)
• MRI (disc)
• Arthrography

Arthroscopy - visual examination of upper joint space

TMJ Disorders

Facial Nerve Palsy

Upper motor neurone lesion → only lower part of face on opposite side (contralateral)

• Cerebrovascular accident
• Multiple sclerosis

Lower motor neurone lesion → whole face on same side (ipsilateral)

• Bell's palsy - Prednisolone 80mg/day x 5 + 5 days (tail off)
• Trauma
• Cerebellopontine angle tumors
• Malignant parotid gland tumor
• Otitis media
• Sarcoidosis
• Lyme disease

HIV Infection and Acquired Immune Deficiency Syndrome (AIDS)