Lecture 2 -Oral Facial Dev & Tooth Dev

What develops in the lower face?

mandible

What develops in the upper face?

frontonasal process

What develops in the midface?

maxillary process

What is the primitive mouth?

stomodeum

What causes the stomodeum to initially be seen as a shallow depression before developing?

oropharyngeal membrane disintegrates

Facial development depends on the ____ (number) major facial processes.

5

What week do the major facial processes form?

4th

Give the 5 major facial processes and the single/paired status.

1 frontonasal, 2 maxillary, 2 mandibular

Which arch is responsible for forming most of the face?

mandibular

Give the top large structure.

frontonasal process

Give the purple and blue processes respectively.

maxillary, mandible

What is the center structure?

oropharyngeal membrane

What is the center black structure?

stomodeum

What are the smallest gray structures?

lens placode

The tongue also develops from_______________

mandibular arch

While the mandibular arch is developing, ___________________ forms within

each side of the arch. Later, as most of the cartilage disappears, the mandible

forms by __________

meckels cartilage, intramembranous ossification

The muscles of _____________________ are derived from the mesoderm as

the primitive muscle cells differentiate, and later from the mandibular arch.

mastication

What is the FIRST part of the face to form after the stomodeum?

mandibular arch

Give the 2 structures that form following the stomodeum.

mandibular processes, mandible arch

What are the two bulges of tissue appear inferior to the

primitive mouth?

mandibular proceses

The mandibular arch will eventually develop into what facial structures?

lower face (lower lip, mandible, mandibular teeth)

What 3 structures do the branchial arches form?

nerves muscles bones

What 4 structures do the mandibular arch form?

V nerve (trigeminal), muscles of mastication, ear bones, sphenoid

What 3 structures does the hyoid form?

VII (facial nerves), facial muscles, ear bones

Give pink.

frontal process

Give black.

oral pit

Give yellow.

maxillary process

Give blue.

mandibular arch

Give orange.

hyoid arch

Give the top arrow.

nasal pit

Give the left structure.

eye

Give the bottom structure.

oral pit

What causes a cleft lip?

lack of mesenchymal growth

Each pharyngeal arches has what 4 components within each mesodermal core:

cartilage, nerve, vasculature, muscle

What are the first two paired arches that develop to the greatest extent?

mandible, hyoid

The first two pharyngeal arches form what parts of face?

middle and lower

The lower four pairs of pharyngeal arches form what?

larynx and neck

What palatal portions form in the 5-6th week?

intermaxillary segment from fused nasal

What palatal portions form in the 6-12th week?

fused palatal shelves from maxillary

What palatal portions form in the 12th week?

all three processes fuse

The 5-6th week forms the _____ palate, the 6-12th week forms the _____, the 12th week forms the ______ palate.

primary, secondary, final

The paired medial nasal processes fuse on the inside of the stomodeum, forming the _______ _______.

intermaxillary segment

The intermaxillary segment is involved in the formation of…

max. incisors, primary palate, nasal septum

Which arch(es) form the anterior, movable part of the tongue?

first branchial

Which arch(es) form the posterior, immovable part of the tongue?

2, 3, 4

What cranial nerves innervate the tongue?

5, 7, 9, 10, 12 (trigeminal, facial, glossopharyngeal, vagus, hypoglossal)

What week does the tongue finish developing?

8

Most congenital malformations of the head and neck occur when the brachial apparatus…

transforms into adult structures

Give the term for “tongue tied”. This is a short lingual frenum attachment.

ankyloglossia

Define macroglossia.

excessively large tongue

Define microglossia.

abnormally small tongue

What is an abnormally small tongue associated with?

underdeveloped mandible

What fails to occur that causes a cleft tongue?

fusion of lateral lingual swellings

Give the term for tooth development.

odontogenesis

Give the 5 stages of tooth development.

initiation, bud, cap, bell, apposition maturation

What kind of tissue is enamel?

calcified, deposited by ectodermal cells

Why does enamel not have a healing ability?

epithelial cells are lost, is acellular

What kind of tissue is dentin?

calcified CT

What direction does dentin grow appositional?

inward toward pulp

What kind of tissue is cementum?

calcified CT

What direction does cementum grow appositional?

outward

What kind of tissue is pulp?

uncalcified loose CT

Give the 4 stages of the life cycle for primary dentition.

development, eruption function, exfoliation

Give the 3 stages of the life cycle for secondary dentition.

development, eruption, function

What embryonic tissues are responsible for odontogenesis?

mesenchyme, ectoderm

What kind of tissue is mesenchyme? Give 3 types.

embryonic CT, dentin cementum pulp

What kind of tissue is ectoderm? Give 1 type.

embryonic epithelium, enamel

What two main events must occur during tooth development?

morphodifferentiation, cytodifferentiation

Define morphodifferentiation.

individual tooth shape

Define cytodifferentiation.

cell diff

Define odontoblasts.

dentin forms

Define ameloblasts.

enamel forms

Define cementoblasts.

cementum forms

Define fibroblasts.

pulp forms