Facial Development Flashcards
Embryology
- Embryo – facial development
•Very early in development
•Starts at 3 weeks I.U.
Tissue Layers
•Ectoderm – skin, hair, lens of eye, nose and external ear lining etc
•Mesoderm – muscle, bone, heart, lungs, blood cells
•Endoderm – throat lining, lung lining
Neural Crest cells
Ectomesenchyme
–Ms CT of pharyngeal arches
–Meninges
–Cranial nerve ganglia
–Pigment cells in skin
–Skin head
Elicit responses from other tissues
–Epithelia tooth development
Facial Development
- Lateral nasal prominence
Medial nasal prominence
Maxillary prominence
Mandibular prominence
Pharyngeal Arch
•Nerves
–Motor
–Sensory
•Muscle
•Cartilage
Arch development
Cartilage
–Meckels cartilage – 1st arch
•Malleus
•Ligaments
•NOT mandible
–Reicharts cartilage – 2nd arch
•Stapes
•Styloid process
Tongue Development
Starts 4 weeks I.U.
•First structures to be completed
•Mesoderm swellings
Tongue Development
Macroglossia
–Downs Syndrome
–Cretinism
–Beckwith Weidemann Syndrome
Palate Development
Primary palate
•Anterior 2-2 region
•Medial nasal and maxillary processes
2.Secondary palate
•Maxillary process
•Starts 6 weeks I.U.
•Completed 12 weeks I.U.
Van Der Woudes Syndrome
1in 28000 live births
•No other features
•Mutation IRF-6 gene
1st arch
Pierre Robin Sequence
1.Micrognathia
2.Macroglossia
3.Gastric reflux
•+/- CP
•Management
–Airway
–Feeding
–Growth - normal
Sticklers Syndrome
1 in 10000
•Connective tissue defect
•Eyes – myopia
•Facial – midface retruded
•Joints – flexible/arthritis
1st and 2nd arch –
Goldenhars Syndrome
1 in 4000 births
•Thymic and parathyroid glands
•Facial
•Prone to infections
•Cardiac
•Learning difficulties
Tooth Development -Stages
- Thickening
- Bud
- Cap
- Bell
- Erupt
