Skull development Flashcards
what are the 5 mesenchymal prominences?
2 mandibular
2 maxillary
frontonasal
what does the frontonasal prominence become?
2 lateral and medial nasal prominences
how does the frontonasal prominence become the lateral and medial prominences?
2 nasal pits develop and ventrolateral aspects
what do the mandibular prominences become?
mandible
lower lip
what do the maxillary prominences fuse with?
lateral nasal prominences
what fuses to form the nasolacrimal groove?
maxillary prominences
lateral nasal prominences
what does the nasolacrimal groove become?
nasolacrimal duct and lacrimal sac
what pushes the medial nasal prominences together?
maxillary prominences
what do the medial nasal prominences form?
philtrum and midline nose
what does the superior frontonasal prominence form?
forehead
bridge of nose
what does the inferior frontonasal prominence form?
allows fusion of the medial nasal processes
what does the lateral nasal prominence form?
alae of nose
what do the maxillary prominences form?
cheeks
lateral upper lip
how do facial anomalies come about?
disruption of devlopment to any facial prominences
what results in hare lip?
fusion failure of maxillary and medial nasal prominences
what results in oblique facial cleft?
fusion failure of maxillary and lateral nasal prominences
what results in macrostomia?
incomplete merging of maxillary and mandibular prominences
what results in median cleft lip?
incomplete fusion of medial nasal prominences
what results in frontonasal dysplasia?
hyperplasia of inferior frontonasal prominences
which prevents fusion of medial nasal prominences
what does neural crest mesenchyme become?
Visceroscranium
hyoid bone
laryngeal cartilage
where is the viscerocranium derived from?
neural crest mesenchyme
what process creates the viscerocranium?
membranous ossification
where is the hyoid bone derived from?
neural crest mesenchyme which becomes pharyngeal arches 2 and 3
where is the laryngeal cartilage derived from?
neural crest mesenchyme which becomes pharyngeal arches 4 and 6
what does the paraxial mesoderm become?
chondrocranium
neurocranium
where is the chondrocranium derived from?
paraxial mesoderm
where is the neurocranium derived from?
paraxial mesoderm
what process forms chondrocranium from paraxial mesoderm?
endochondral ossification
what process forms neurocranium from paraxial mesoderm?
membranous ossification
what sutures mark the site of the posterior fontanelle?
lambdoid
sagittal
when do the lambdoid and sagittal sutures close?
3-6 months postnatally
what sutures mark the site of the anterior fontanelle?
sagittal
coronal
frontal
when do the sagittal coronal and frontal sutures close?
1.5-2 years postnatally
