clinical examination of the mouth and tongue

Last reviewed 01/2018

Inspection of the mouth and tongue may yield important information:


  • the tongue is blue in patients with central cyanosis
  • the tongue is red and sore in iron- and B-vitamin -deficient patients
  • the tongue is enlarged in:
    • acromegaly
    • amyloidosis
    • myxoedema
  • the tongue is spastic in motor neurone disease


  • bleeding gums are characteristic of:
    • periodontal disease
    • leukaemia
    • scurvy
  • hypertrophied gums may indicate chronic phenytoin use
  • a blue line along the margin of the teeth indicates lead poisoning


  • yellow teeth may indicate tetracycline use in early life
  • caries may be cause local and systemic infection
  • hypoplastic teeth may indicate dentinogenesis imperfecta
  • Hutchison's teeth are seen in congenital syphilis


  • angular stomatitis is common in iron deficiency
  • aphthous ulceration
  • leukoplakia
  • herpes simplex infection
  • pigmented lesions of Peutz-Jeghers syndrome
  • white reticular lesions of lichen planus
  • the tight mouth of scleroderma
  • oropharyngeal cancer may present as an ulcer or a mass