1. ODONTOGENESIS
Dr. Brian E. Esporlas

2. Stages in the life cycle of a
tooth
1. Growth
Physiologic process
a. Initiation
b. Prolifiration
c. Histodifferentiation
d. Morphodifferentiation
e. Apposition
2. Calcification
3. Eruption
4. apposition

3. 3 developmental process before
function
 Grow
 Calcify
 Erupt
 Unlike kidney and heart.. Afte growth ..
Function
 Unlike bone… growth and calcify… function

4. Initiation stage
 6th weeks intra
uterine life: first sign
of tooth
development
 Dental lamina:
represent the first
sign of tooth
development. This
is the GERMINAL
BAND OF
EPITHELIUM

5. Function of dental lamina
 Initiate the development of the whole
deciduous dentition
 Initiate the development of the succedenuous
teeth, by proliferation of bud from enamel
organ
 Initiates the development of the accesional
teeth from the distal extention of the dental
lamina

6. Vestibular lamina
 After the dental
lamina, the
vestibular lamina will
arise as another
ectodermal
thickening, but
anterior to the dental
lamina.
 Then this will split to
form the vestibular
groove the future
vestibule.

7. Bud stage
 At certain point on DL
representing the location of
10 manibular and 10
maxillary deciduous teeth
cells multiply still more rapidly
and form a knob like
projections oward the
mesoderm
 Down ward growth creating
dental sac, dental papila and
dental organ
 For the mandibular anterior
6th to 7 weeks
 Max anterior 7th to 7 ½ week
 Deciduous molars 8th week

8. Cap stage
 The epithelial bud
will continue to
proliferate and
expand latrally
 Defferent part of the
bud will show
unequal growth
leading to the
formation of a cap
stage dental organ(
with invagination)

9. 3 layers of cap stage
 Outer dental epithelium
 Inner dental epithelium
 Stellate reticullum
(enamel pulp,
 Filled with mucoid fluid
rich in albumin)
Star shape cell
 During late cap stage
 Stratum intermedium :
flat cell between inner
dental epithelium and
stalate reticulum.

10.  Enamel knot: bud like enlargement , germinal
center for the demand of cell growth of tooth
 Enamel cord: vertical extension of the enamel
knot that maintain the cap shape dental organ
 Enamel naval: attachment of enamel cord to
outer dental epithelium

11. Bell stage
 .Dental lamina
2.Dental sac or follicle
3.Outer dental
epithelium
4.Stellate reticulum
5.Inner dental
epithelium
6.Dental papilla
7.Enamel cord
8.Enamel navel
9.Blood vessel
10.Enamel niche
11.Successional
dental lamina

14. Dental papilla
 The invaginated part of
the dental organ is
occupied by
condensation of
mesenchymal tissues.
 Peripheral cells (
cuboidal – columnar)
differentiates into
odontoblast through the
stimulation of the cell of
the IEE
 ODONTOBLAST –
formtive cell of dentin
 Central part will be the
pulp

15. Membrana preformativa
 Former basement
membrane
(separating the
dental papilla from
the IDE
 FUTURE dentino
enamel junction

16. Tooth germ and dental sac
 During bell stage, the mesodermal tissue
arround the enamel orgarn and the dental
papilla differentiates into connective tissue
capsule, dental sac.
 As a resulth 3 tooth germs are developed.
a. Dental organ – will give rise to enamel tissue
b. Dental papilla – give rise to dentin and pulp
c. Dental sac – give rise to cementum, pdl and
alveolar bone.

17. Dental organ
 Give rise to enamel
 Play an active role in the formation of dentin
 Play a role in formation of root via HERS or
hertwig’s epithelial root sheath. (from the
junction of the IDE and ODE)
 Produces enamel cuticle: last product of
ameloblast
 Remain as epithelial attachment of the neck of
the toth after the tooth has erupted

18. histodifferentiation
 Peripheral cells of the inner dental epithelium
differentiates into ameloblast (formative cells
of enamel)
 With the influence of the ameloblast, the
formative layer of dentin known as the
ODONTOBLAST are formed from the cells of
the periphery of the dental papill

19. Morphodifferentiation
 The shape and form of the crown is determine
by the membrana preformativa

20. Fate of dental lamina
 The remnant should be calcified and be
resorbed by osteoclast because it has no
function
 But, some group of epithelial cells may persist
to stay (called gland of serres) and
differentiates into ENAMEL
MASS, SUPERNUMERARY
TEETH, TUMORS OR CYST (
ameloblastoma)