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cementum.pptx
1. PRESENTED BY – Dr. SONAM RANI
PRESENTED TO – Dr. Viniti Goel(HOD)
Dr. Deepak Grover( professor)
Dr. Deepak Bala(Reader)
Dr.Tanvi Ohri (senior lecturer)
My seniors – Dr. Shikha, Dr. Jaspreet, Dr. Sarvani,
Dr. Vikram, Co-PG- Dr. Malti
CEMENTUM
2. •CEMENTUM – a part of periodontium which covers
the anatomical roots of human teeth 1
•First demonstrated microscopically by 2 Pupils of
Purkinje in 1835 ( Frankel & Raschkow)1
•Its prime function is to give attachment to collagen
fibre of PDL
3. Cementum is the calcified ,avascular mesenchymal tissue that
forms the outer covering of the anatomic root( Newman et
al,2006)
Cementum or simply cement is a component of the
tooth as well as of the periodontium . covers the entire
surface of anatomical roots of it is a mineralized
connective tissue, in part not unlike bone, that
teeth(Shroeder)
4. PERMEABLITY
•More permeable than
dentine
•Also endotoxins
secreted by bacteria gets
absorbed onto the
superfecial layer of
cementum
• Dimnishes with age
•Canaliculi of cementum
may be contiguous with
dentinal tubuli( BLayney
et al, 1941)
COLOUR
• Light yellow
•Distinguished from
enamel as it Lack
luster and is darker in
hue
•Distinguished from
dentine as it is lighter
in colour
HARDNESS
•Hardness of fully mineralized
cementum is less than that of
dentine
5. THICKNESS
•Thinnest cervically (20-50 μm) & thick toward apex (150-
200 μm)
Distal surface is thicker than the mesial surface because of
functional stimulation from mesial drift over t ime
( Dasmalch et al 1990)
6. On the basis Inorganic
material
Organic
material
water
Wet –weight2 65% 23% 12%
Dry-weight1 45-50% 50-55%
volume1 45% 33% 12%
INORGANIC PORTION
1. Calcium & phosphate (hydroxyapatite)
2. 0.5-0.9% magnesium
3. trace element ( copper,zinc & sodium)
4. Highest fluoride content of All mineralized tissue
7. ORGANIC PORTION
. Type 1collagen mainly (proteoglycans)
.Other type III,IV,XII,XIV
NON COLLAGENOUS PROTEIN
. Alkaline phosphate
.Bone sialoprotein
.Dentine matrix protein
.Dentine sialoprotein
.Fibronectin
.Osteocalcin
.Osteonectin
.Proteoglycans
.Proteolipids
.Tenascin
.Several growth factor
8. 2 unique cementum molecules –1. Cementum attachment protein
(CAP)-
2.An insulin like growth factor
CAP - as present only in cementum (marker to differentiate bone and
cementum )
- it helps in attachment of mesenchymal cells to the extracellular
matrix
Proteoglycans – play major role in regulating cell–cell and cell–matrix
interactions
associated with cementocytes and cementoblasts .
Matrix of bone and cementum shows similar growth factors
(TGBF,BMP’s, FGF,IGF,EGF,PDGF)
9. It take place in two phases
Matrix formation
Mineralization
There are 3 type of cell responsible
Cementoblast
Cementocytes
Fibroblasts
All of these cells are derived from the ectomesenchymal cells
10. FORMATION OF CEMENTOBLAST
Cementum formation results from either of two ways
from HERS
From dental follicle
• Soon after HERS break down
Epithelial cells of
hertwig’s root sheath
undergo epithelial
mesenchymal
transformation
cementoblast
11. Cementoblast are Ecto-mesenchyme in origin
These cells are rich in numerous Mitochondria ,well
formed Golgi apparatus, and larger amounts of
Granular Endoplasmic Reticulum
Electron microscopically cementoblasts
show Mitochondria and Endoplasmic
reticulum
www.periobasic.com
12. Cementoblast synthesize collagen & protein
polyasaccarides
Cementoblasts derived from dental follicle have
similar phenotype to osteoblasts ,it is shown to be
involed in formation of Cellular Intrinsic
fiber Cementum.
Cementoblasts derived from HERS has different
phenotype than osteoblasts and are shown to be
involved in Acellular Intrinsic Fiber Cementum
13. entrapped cementoblasts
in the mineralized cementum
They first project numerous cytoplasmic process into
the loose dentinal matrix and immediately commence to
implant the initial collagen fibrils
www.dentalimage.com
Ultastructure
of
cementocyte
CEMENTOCYTES
15. Based on location
Based on time of formation
RADICULAR CORONAL
PRIMARY SECONDARY
16. BASED ON CELLULARITY
BASED ON THE PRESENCE OR ABSENCE OF
COLLAGENOUS FIBRILS
ACELLULAR CELLULAR
FIBRILLAR AFIBRILLAR
17. BASED ON THE ORIGIN OF COLLAGENOUS FIBRILS
INTRINSIC FIBRE EXTRINSIC FIBRE
Which are formed due to
cementoblast activity
•Are found between the
Sharpey’fibres
•Arranged either
randomly or parallel to
the surface of the
cementum
The first group is made
of the embedded parts of
the principal fibres of the
periodontal ligaments
which are known as
Sharpey’s fibres
(extrinsic group)
The are formed by the
fibroblast of PDL
19. ACELLULAR CEMENTUM 1
• Thickness is 20-50 µ
• It is clear and structureless
• Covers the coronal half of the root.
• Incremental lines of Salter are parallel to the surface.
• Alternating layers of
acellular and cellular cementum could be seen
Acellular
16-60 um
Cellular
150-200 um www.dentalimage.co
m
20. CELLULAR CEMENTUM1
• Also known secondary cementum, contain cementocytes
• Formed after tooth reaches it’s occlusal plane
• More rapidly formed ,less calcified
• Mainly involved in adaptation ,repair of cementum
• Thickest around the apex
Cellular cementum
Acellular cementum
www.juniordental.com
21.
22. • Found on mature enamel surfaces i.e
coronal cementum
• Appear as cemental spurs or cementum
islands on the crown of erupted teeth
• It represent an aberration of the
developmental process in which parts
of the REE disaggregates and allows
cells from the dental follicle to interact
with the exposed enamel matrix,
leading to cementum deposition www.dentalimage.com
23. It extend from cervical margin to apical 1/3rd
Only type of cementum seen in single rooted
teeth(mostly)
Composed of densely packed bundles of sharpey’s fibers
Thickness 30-230μm
24. Location found in middle and
apical third
Contains cells but no extrinsic
collagen fibres.
Formed by cementoblasts
It has major role in adaptation &
repair
Its formation on the developing
root commenses in closest
proximity to the advancing root
edge
www.periobasic.com
25. Alternative layer of acellular & cellular cementum
Composed of extrinsic & intrinsic fibres & contain cells
Form bulk of secondary cementum
Co-product of cementoblasts & fibroblasts
Jan Lindhe ; Clinical Periodontology & Implant
Dentistry , 5th edition, vol 1 , chap-1, 8-
15
30. Union of the root of two or more adjoining completely formed teeth
along the line of cementum
Etiology – .traumatic injury
. crowding of teeth
. hypercementosis associated with chronic
inflammation
www.dentalimage.com
31. Hemispheric structures consisting entirely of enamel
or contain underlying dentin and pulp tissue
• Projects from surface of root more in maxillary
molars
• Majority in furcation area or CEJ
www.periobasic.com
32. Defined by Orban as an abnormal thickening
of the cementum,it may be diffused or
circumscribed
SITE : Premolars affected most frequently
Frequency increases with age
33. Pathological wearing away of tooth substance through some
abnormal mechanical process
CAUSES – .faulty toothbrushing
. habitual abrasion
. occupational abrasion
.due to faulty clasp design
CLINICAL FEATURE - V shaped or wedge shaped ditch on root
side of CEJ in teeth with some gingival
recession
Notch have sharp angles and highly
polished dentin surface
34. Root resorption occurs as a result of differentiation
of macrophages into osteoclasts in surrounding tissue.
LOCAL FACTOR FOR CEMENTUM
RESORPTION
•TRAUMA FROM OCCLUSION
•ORTHODONTIC MOVEMENT
•PERIAPIACL DISEASE
• PRESSURE FROM MALIGNANT
ERUPTING TEETH
Which if in close proximity to the root surface will
resorb the root surface cementum and underlying root
dentine.
SYSTEMIC CONDITION
PREDISPOSING TO OR
INDUCING CEMENTUM
•CALCIUM DEFICIENCY
•HYPOTHYROIDISM
•PAGET’S DISEASE
•HEREDITARY FIBROUS
OSTEODYSTROPHY
35. CEMENTOBLASTOMA12 arises from the cementoblast cells of the
cemental layer of the apical third of a vital teeth
Age – second and third decade of life
Sex- more in males
CLINICAL
PRESENTATION
. Slow, enlarging,
bony hard swelling of
the jaw
. Both buccal &
lingual plates
are expanded
uniformly
. Dull sound on
percussion
. Low grade
intermittent pain
36. RADIOGRAPHICAL FEATURES
• Large , dense , radiopaque mass that is often attached to one
or more vital tooth roots
• Lesion is surrounded by thin zone of radiolucency at the
periphery
• Roots adjacent exhibits resorption
at their apical third
TREATMENT – surgical excision
37. Relatively uncommon odontogenic
neoplasm occurring in relation to
the periapical bone and cementum
at the root apex of vital tooth
Age- usually third and fourth
decades of life
Sex- more in females
Site – mostly in relation to
mandibular anterior teeth
Clinical presentation
Mostly asymptomatic usually small
and multiple in number found in
association with vital teeth
38. RADIOGRAPHIC FEATURES
Varies in 3 stages-
• Osteolytic stage- initial stage in which lesion appears as a
small, well defined,radiolucent area near the apex of tooth
• Cementoblastic stage- lesion appears as a radiolucent and
containing small radiopaque foci
• Mature stage- cementoma presents a well defined radiopaque
mass at root apex being surrounded by thin radiolucent zone
TREATMENT
Periodic observation and time to time
vitality test
39. 4.FOCAL CEMENTOOSEOUS DYSPLASIA11
◦ Benign fibroosseous condition
◦ SITE: Single site of involvement
:Can be seen in dentulous and edentulous
patients
: Mostly posterior mandible
◦ Asymptomatic lesion
◦ Needs no treatment but follow up is essential as it
can progress to a condition called florid cemento-
osseous dysplasia
RADIOGRAPHIC FEATURE- varies from completely
radiolucent to dense radiopaque
40. CLEIDOCRANIAL DYSPLASIA12
Rare genetic disorder characterized by
abnormal growth of the bones in
clavicle,skull and the face with a tendency
for failure of tooth eruption
Origin-autosomal dominant
Clinical features
* Multiple embedded and impacted
permanent teeth
* Multiple retained deciduous teeth with
delayed eruption of permanent teeth
* Roots of the teeth are often thin and
short
12.Oral & Maxillofacial
pathology, Neville, 2nd
edition
41. RADIOGRAPHIC FEATURES
• Absence of cellular cementum
• There may be hypoplasia of alveolar process
• Ascending ramus of mandible is narrower
TREATMENT
No treatment is possible
42. uncoordinated phases of bone resorption and
subsequent deposition of new bone in the same area
resulting in severe distortion and weakening of
affected bone
Age- usually fifth,sixth and seventh decade of life
Sites – more in maxilla
Oral manifestations
- Diastema , loosening of teeth
- Flattening of palate
- Retroclination of incisors and palatoversion of
posterior teeth
- Maxillary lesions often cross midline and involve both
quadrants of the jaw
- Hypercementosis of teeth
- Pathological fractures in affected bones
9.Shafer’s textbook
of oral pathology,
6th edition
43. PAPILLON LEFEVRE SYNDROME
It is typically characterised by:
hyperkeratosis affecting the palms
of the hands and soles of the feet
and
It consists of dramatically advanced
early periodontitis in both
deciduous and the permanent
dentitions.
Teeth lacks osseous support and
rapid loss of attachment occurs.
Radiographically teeth appear to
float in the soft tissue
Textbook of Oral Medicine, Anil
Govindra Ghom, 2nd edition
44. A rare autosomal recessive
disease that damages
immune system cells, leaving
them unable to fight off
invaders such as viruses and
bacteria effectively.
Have repeated and persistent
infections starting in infancy
or early childhood including
periodontal diseases of the
primary dentition
Textbook of Oral Medicine, Anil
Govindra Ghom, 2nd edition
45. 1. Orban’s oral histology and embryology ,12th edition ,pg
137
2. Berkovitz Oral anatomy , histology and embryology ,4TH
EDITION, PG 169- 178
3. Bosshardt DD, Selvig KA. Dental cementum: the
dynamic tissue covering of the root. Periodontol 2000
1997; 13: 41-75
4. Saygin NE, Giannobile WV, Somerman MJ. Molecular and
cell biology of cementum. Periodontol 2000; 24: 73-
98.
5. Donald A. Kerr. The Cementum: Its Role In Periodontal
Health and Disease. Journal of Periodontology.July
1961, Vol. 32, No. 3, Pages 183-189
