Kharkov National Medical University

1
Kharkov National Medical University
LECTURE for dentistry students

• Department of
• Histology, cytology and embryology

2
MICROMORPHOLOGY AND EMBRYOLOGY OF THE ORAL CAVITY
3
FACE AND ORAL CAVITY ORGANS DEVELOP FROM
MESENCHYME, ECTODERM AND ENDODERM

• On the 3-4-th week the stomatodaeum (oral bay -
  ectodermal invagination ) is formed.
• This will fuse with the gut through
  oropharyngeal membrane.

4
Oropharyngeal Membrane
Amnion gut
Stomatodaeum Yolk sac
5
(No Transcript)
6

• Pharynx wall forms 4 thickenings pharyngeal
  arches

Pharynx
7
1. Each consists of
mesenchyme, outer ectoderm and inner endoderm.
2. Arches mesenchyme provides the skeletal
muscle and c.t.
3. They
form 1) face, nasal cavities,

2) mouth, larynx,

3) pharynx, and neck.


8
(No Transcript)
9
Development of oral cavity begins with the
formation of frontal process over the oral bay
and growth of the 1-st ph. arch, which divides
on maxillar and mandibular processes
10
Frontal process
Ectoderm
Pharyngeal Pouches
11
Frontal Process
Maxillary
Mandibular
12
In the frontal process are formed olfactory pits.
They divide f.p. on medial and lateral nasal
processes Latter fuse with maxillar and
mandibular processes and nose and lips appear
13
NASOMEDIAL PROCESS Nasolateral process
Olfactory pit
MAXILLARY PROCESSES
grow to meet just off the midline, which is
occupied by the fusing medial nasal processes
FRONTONASAL REGION gets back by merging
nasomedial processes
FACE
14
7-w/19mm EMBRYO
NASOMEDIAL PROCESS
EYE
MAXILLARY PROCESS
MOUTH
MANDIBULAR PR.
HYOID BONE
LARYNGEAL CARTILAGES
FACE
15
(No Transcript)
16
Malformation 1.Clefts involving the upper
lip 2.Unilateral and 3.Bilateral cleft lip
result if maxillary and medial nasal processes do
not fuse.
4. Cleft palate leaves the
nasal and oral cavities connected.
This
causes nursing problem for the new born.
17
FACE
18
Bilateral Facial clefts and bilateral cleft lip
Cleft Upper lip hairlip
19
PALATE developes by fushion of maxillar processes
20
PALATAL DEFECTS I Partial failures to fuse
UNILATERAL CLEFT LIP
ANTERIOR CLEFT PALATE Incomplete
Unilateral
CLEFT UVULA
Lateral palatines
21
PALATAL DEFECTS II Failures to fuse
COMPLETE UNILATERAL ANTERIOR CLEFT Palate
Lip
POSTERIOR CLEFT PALATE
Can occur independently can be partial anterior
can be bilateral
PALATE
22
(No Transcript)
23
(No Transcript)
24
TONGUE
25
ORAL CAVITY IS LINED BY MUCOSA, CONSISTS OF
STRATIFIED NONKERATINIZED EPITHELIUM AND C.T.
LAMINA PROPRIA FUNCTIONS 1. PROTECTIVE 2.
SECRETORY 3. SENSORY
26
(No Transcript)
27
ORAL MUCOSAE Classification
MASTICATORY (CHEWING)
Epithelium undergoes keratinization
HARD PALATe
GINGIVAe
SPECIALIZED
DORSAL LINGUAL
LINING (COVERING)
LABIAL
BUCCAL
ALVEOLAR
SOFT PALATAL
28
LIP
2. RED MARGIN VERMILION transitional
3. LABIAL MUCOSA thick inner
GLAND mucous
1. HAIRY SKIN anterior
MUSCLE
29
(No Transcript)
30
HARD PALATE Cross-section
PALATE BONE why it is hard!
Periosteum
2. Palatal seam
1.Fatty zone anterior 3. Glandular zone
MUCOUS GLANDS - posterior
STRATIFIED SQUAMOUS EPITHELIUM slightly-keratinize
d
31
TONGUE - dorsum
TONSILS
CIRCUMVALLATE PAPILLA
Trench
FUNGIFORM PAPILLA
FILIFORM PAPILLAE General sensation
Taste bud
FOLIATE PAPILLAE on the lateral t.
32
SALIVARY GLANDS - major minor
Parotid
Sub-mandibular
Sub-lingual
MINOR Labial. Buccal. Lingual. Palatal
33
(No Transcript)
34
MATERIALS Water
Mucins (glycoproteins) Antibodies IgAs Lysozyme
Defensins Ions - tooth mineral Amylase
Iodine
35
SCHEME OF SALIVARY GLANDS
SECRETORY UNITS

General duct
Lobule
Interlobular duct
STRIATED duct
Intercalated ducts
See SALIVA Powerpoint
36
(No Transcript)
37
(No Transcript)
38
(No Transcript)
39
SUBLINGUAL GLAND (muco-serous)
INTER LOBULAR DUCT
MIXED MUCOUS TUBULES
SEROUS demilune
MUCOUS LE
STRIATED DUCT (few)