Syndromes Relevant to Dentistry

The word syndrome is derived from greek and means 'runs together'. Syndromes refer to medical conditions that have signs and symptoms that often occur together. A syndrome has no known cause, but may still be referred to as a syndrome even after the cause has been discovered, e.g. AIDS. If a dentist is alerted to one or more signs and/or symptoms of a suspected syndrome, they should look out for the other common signs and symptoms of the syndrome.

Neural Crest Syndromes

• DiGeorge Syndrome - remember the description of this syndrome with the mnemonic CATCH 22 - Cleft palate, Abnormal facies, Thymic aplasia, Cardiac defects, Hypocalcaemia, 22q11.2 deletion. May be caused by migration defects of neural crest derived tissues.
  
• Hemifacial microsomnia - lower half of face affected (on one or both sides). Most commonly mouth, mandible and ears.
• Sturge-Weber Syndrome - most obvious feature is a port-wine stain on the face. Neurological abnormalities are also commonly seen as angiomas can develp on the brain (the same side as the port-wine stain). Glaucoma also commonly develops. Increased vascularity of the hard and soft tissue of the jaw on the same side as the port-wine stain may occur and this can cause dental problems such as swelling, premature tooth eruption and periodontal problems.
  
• Thalidomide malformations - phocomelia (very short or absent long bones). (S) enantiomer of thalidomide thought to be the neural crest toxin.
  
• Treacher-Collins - often present with underdeveloped facial bones, micrognathia, microtia, cleft palate. Half have hearing problems due to defects in middle ear bones.