Cleidocranial dysplasia

Cleidocranialdyplasia

1. Cleidocranial dysplasia Maryam Arbab House Officer SBDC

2. DEFINITION It is a condition characterized by defective development of the cranial bones and by the complete or partial absence of the collar bones (clavicles). It is also characterized by late ossification of cranial sutures and delayed tooth eruption. ( cleido = collar bone, cranial = head, dysplasia = abnormal forming ) Also known as Cleidocranial Dysostosis and Marie- Sainton Disease.

3. ETIOLOGY It is familial and appears as true dominant characteristic. Mutations in the core binding factor alpha 1 (CBFA) gene located on chromosome 6p21 is the cause of cleidocranial dysplasia. A parent with the condition has a 50:50 chance that each of their children will have the condition. Boys and girls stand an equal chance of being affected

4. EPIDEMIOLOGY The incidence is estimated at 1:200,000.

5. CLINICAL FEATURES Delayed closure (ossification) of the space between the bones of the skull (fontanels) Premature closing of the coronal suture Protruding jaw and protruding brow bone (frontal bossing) Hypertelorism – wide nasal bridge due to increased space between the eyes

6. hypertelorism

7. High arched palate or possible cleft palate Short stature Osteopenia - decreased bone density

8. ORAL MANIFESTATIONS Dental abnormalities seen in cleidocranial dysplasia may include: Delayed loss of the primary teeth Delayed appearance of the secondary teeth Unusually shaped, peg-like teeth Misalignment of the teeth and jaws (malocclusion) Supernumerary teeth, sometimes accompanied by cysts in the gums .

9. Maxilla & paranasal sinuses are underdeveloped resulting in maxillary macrognathia. Complete absence of cementum. Roots of teeth are often short and thinner than normal. Crown may be pilled as a result of enamel hypoplasia.

10. DIAGNOSIS Radiological imaging helps in confirming the diagnosis. Clavicles are typically reduced to single or double fragments on each side with middle part being deficient. Changes are asymmetric. Large fontanelles, multiple wormian bones and underdeveloped paranasal sinuses.

11. TREATMENT No specific treatment. But certain procedures can be performed : Around 5 years of age, surgical correction may be necessary to prevent any worsening of the deformity. Craniofacial surgery may be necessary to correct skull defects

12. Dental treatment : Due to the fact that the dental problems are the most significant complications, appropriate dental/orthodontic work is vital. Some of the suggested treatment options include the following: Apply dentures over the unerupted teeth.

13. Teeth removal as they erupt, because very little bone structure would be left if the supernumerary, impacted, and unerupted teeth were all extracted at once. Speech therapy may be required during periods of dental treatment. Retained deciduous teeth should be restored if they become carious.

14. In case of open fontanelle, appropriate headgear may be advised by the orthopedist for protection from injury.