Face Development Flashcards
When does the external face begin to develop?
Week 4-6
When does the palate begin to develop?
Week 6-8
How does the oral cavity develop?
Week 3 - oropharyngeal membrane appears
During 4th week - breaks own to become oral cavity
What are the sources of the structures of the external face?
Frontonasal prominence
Mandibular prominence
Maxillary prominence
What forms the frontonasal prominence?
Proliferation of mesenchymal neural crest cells ventral to the forebrain
What forms the mandibular and maxillary prominences?
1st pharyngeal arch
What lies between the maxillary prominences?
Stomatodeum - precursor to the mouth and pituitary gland
How does the nose develop?
Raised bumps called nasal placodes arise on both sides of the frontonasal prominence
Form nasal pits - with lateral and medial nasal prominences
As maxillary prominences grow - nasal prominences pushed into midline
Maxillary prominences fuse with nasal prominences
Fuse in midline
What is derived from the frontonasal prominence?
Forehead
Bridge of nose
What is derived from the medial nasal prominence?
Philtrum
Primary palate
Upper 4 incisors + associated jaw
What is derived from the lateral nasal prominence?
Sides of the nose
What is derived from the maxillary prominence?
Cheeks
Lateral upper lip
Secondary palate
Lateral upper jaw
What is derived form the mandibular prominence?
Lower lip
Lower jaw
What separates the oral cavity from the nasal cavity?
Development of the palate
How does the palate develop?
Fusion of medial nasal prominences creates intermaxillary segment
Intermaxillary segement = primary palate
Maxillary prominences expand medially to give palatal shelves
Palatal shelves advance medially fusing superior to the tongue in the midline
