Syndromes and Other Rare Diseases

Question 1

Special dental considerations

Answer 1

-Patients with rare diseases often have special health care needs:
1. Dysmorphic features can cause psychosocial challenges leading to reduced motivation and poor self-care
2. Affect quality of life
3. Often affect multiple organ systems requiring specialized, multidisciplinary oral health care
-Make special effort to create a positive dental experience

Question 2

Brachycephaly

Answer 2

Wider (M-L) and shorter head (A-P). May also have increased head height
-Due to premature fusion of coronal suture or external deformation (prolonged lying on the back)

Question 3

Dolichocephaly (Scaphocephaly)

Answer 3

Longer (A-P) head
-Due to premature fusion of the sagittal suture or from external deformation

Question 4

Cleidocranial Dysplasia

Answer 4

-Autosomal dominant in most cases
-Defect of the RUNX2 gene involved in osteoblastic differentiation and odontogenesis

Question 5

Clinical features of Cleidocranial Dysplasia

Answer 5

Skull
-Brachycephaly, frontal bossing, open fontanels, wormian bones

Skeleton
-Clavicles are hypoplastic/malformed or absent
-Ocular hypertelorism

Oral
-High, narrow palate and/or clefting, short lower face height, delayed/failed eruption, supernumerary teeth

Question 6

Cleidocranial Dysplasia Tx

Answer 6

-Protect fontanels- remain open or show delayed closure
-Treat only the dental problems:
1. full-mouth extractions/dentures
-Removal of primary teeth with extrusion of permanent teeth

Question 7

Mandibulofacial Dysostosis

Answer 7

-Aka: Treacher Collins Syndrome
-Mostly new mutations, 40% autosomal dominant
-Variable expressivity

Question 8

Clinical Features of Mandibulofacial Dysostosis

Answer 8

Skull/Face
-Bird-like face
-Hypoplastic zygoma –> downslanting eyes
-Colobomas - specifically a notch in outer lower portion of the eyelid
-Missing eyelashes
-Ear anomalies, may have hearing deficits
-NO cognitive deficit

Oral
-Underdeveloped mandible with retruded chin
-Macrostomia (with lateral facial clefting)
-Coronoid and condylar hypoplasia
-High arched palate, some have clefting

Pharyngeal hypoplasia can lead to respiratory difficulties and lead to death

Question 9

Crouzon Syndrome

Answer 9

-Aka: Craniofacial Dysostosis
-Due to craniosynostosis = premature closing of sutures
-Autosomal dominant
-Possibly caused by a mutation in fibroblast growth factor receptor 2 (FGFR2)

Question 10

Crouzon Syndrome Clinical Features

Answer 10

Skull
-Variety of head shape changes (brachycephaly, dolichocephaly or trigonocephaly [triangle-shaped]) due to craniosynostosis, digital markings (beaten metal), increased intracranial pressure

Face
-Hypertelorism, strabismus, ocular proptosis due to shallow orbits, maxillary hypoplasia

Oral
-High arched/narrow palate, Class III malocclusion

Question 11

Crouzon Syndrome Tx

Answer 11

-Correct strabismus early (<3yrs) or blindness can occur
-Open sutures to prevent retardation (it is uncommon to see marked mental deficiency)
-Midface advancement