Development Of Orofacial Structrues Flashcards
Facial development depends on inductive ____ between the forebrain, frontonasal region, and developing eye
Five facial primordial appear during early ____ week as prominences around the stomodeum (entrance to oral cavity)
What are they?
What separates the prominences from the cavity of primordial pharynx?
4th
Maxillary prominences (2) Mandibular prominences (2) Frontonasal prominence (1)
Oropharyngeal membrane
When does facial development occur?
____ surrounds the ventrolateral part of the forebrain. The frontal part becomes the ____; nasal portion becomes the roster all boundary of the ____ and ____; form from ____ of the forebrain and midbrain.
Weeks 4-8
J
J
Lower jaw and lower lip are the first parts of the face to form. The ____ disintegrates and there is extension and fusion of _____ towards the midline.
Oropharyngeal membrane
Mandibular prominences
By end of ____ week, nasal placodes form on the inferolateral part of the ____. They are oval thickening of surface ectoderm that are primordia of _____.
4th
Frontonasal prominence
Nasal epithelium
Placodal edges proliferate to produce _____ and _____. The nasal placodes lie in depressions called ____ that form the nostrils anal nasal cavities. _____ forms the alae (sides) of the nose.
Medial and lateral nasal prominences
Nasal pits
Lateral nasal prominences
_____ grow medially towards each other and the median nasal prominences. This results in movement of the median nasal prominence towards the midline.
Lateral nasal prominence is separated form the maxillary prominence by a cleft called ____.
Theses two prominences merge at ____ week and contribute to _____.
Maxillary prominence
Nasolacrimal groove
6th
Upper lip
During ____ weeks, the medial nasal prominences merge with the maxillary and lateral nasal prominences.
They form the ____ that becomes the upper lip/philtrum, premaxillary part of maxilla, primary palate.
7-10
Intermaxillary segment
Mesenchyme in PA2 forms ____ innervates by the facial N.
Mesenchyme in PA1 forms _____ innervated by trigeminal N.
Facial muscles
Muscles of mastication
As face develops, nasal placodes are depressed forming ____.
Expansion of the MNP and LNP mesenchyme causes the nasal pits to deepen forming _____.
Nasal pits
Primordial nasal sacs
Nasal sacs grow dorsally and ventrally to the developing forebrain. Sacs are separated from the oral cavity by _____. Ruptures end of ___ week.
Oronasal membrane
6th
Palatogenesis begins ____ week and completed by _____ week.
The critical period is the end of the ___ week to beginning of ___ week.
6th; 12th
6th; 9th
Merging of the MNP forms the ____. This is a wedge-shaped mass of mesenchyme between the maxillary prominences and forming the ______.
Median palatine process (primary palate)
Premaxillary part of the maxilla
Secondary palate develops during early ____ week from ____.
6th
Lateral palatine processes (palatal shelves)
F
F
Bone gradually develops in the primary palate forming the ____, which lodges the incisor teeth.
Bone extends from maxillae and palatine bones into lateral palatine processes to form the ____.
Nasopalatine canal persists in the median plane, represented in the adult hard palate by the ____.
Premaxillary part of maxilla
Hard palate
Incisive fossa
The posterior portions of the hard palate do not ossify. They extend posteriorly and fuse forming the ____ and ____.
____ is the line of fusion.
Soft palate and uvula
Palatine raphe
____ extends through upper lip; clefts nose and/or maxilla
Cleft lip
____ is a cleft of secondary palate to incisive fossa.
Cleft palate
Nasal septum forms from down growth of the internal parts of the merged ____.
Fusion of nasal septum and palatine processes begin anteriorly during ___ week and is completed posteriorly during ____ week.
Median nasal prominences
9th; 12th
_____ appears at the end of the 4th week; it is the first indication of tongue development.
Median lingual swelling
J
J
The pharyngeal part of the tongue are formed from the ventromedial parts of the PA2 fuse
N
H
H
What are three tongue abnormalities?
Glossoschissis (Bifid tongue)
Ankyloglossia
Macroglossia (large tongue)
The skull is divided into two parts?
Neurocranium: bony case that encloses the brain
Viscerocranium: bones comprising the facial skeleton
N
N
N
N
N
N
Membranous viscerocranium
J
Premature fusion of cranial sutures is called ___.
Scaphocephaly
Brachycephaly
Plagiocephaly
Trigonocephaly
Craniosynostosis
Premature closure of sagittal suture -> cranium becomes long narrow and wedge shaped
Premature closure of the coronal suture
Premature closure of the coronal suture on one side
Premature closure to the frontal suture
Odontogeneses/ teeth development from reciprocal inductions between ____ induced mesenchyme and overlying epithelium.
Neural crest
Tooth bud is invested by ____.
Consists of enamel organ, dental papilla, and dental sac.
Mesenchyme
