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No.
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Question
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Answers
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1
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On dry weight basis, cementum has
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45% to 50% inorganic substances
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2
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Fluoride level is highest in
|
Cementum
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3
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The major constituent of collagen in
cementum belongs to |
Type I collagen
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4
|
Cementum formation occurs after
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Radicular dentin formation. This occurs
after the dentin deposition occurs along the inner enamel epithelium of Hertwig’s root sheath and its subsequent degeneration. |
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5
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Cementum is formed from cells of
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Dental sac
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6
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Cementoblasts are differentiated from
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Undifferentiated mesenchymal cells
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7
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Breakdown of Hertwig’s epithelial root
sheath involves degeneration of the basal lamina in the |
Outer enamel epithelium. The basal lamina is
reported to break down in the outer enamel epithelium. |
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8
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Cementoid refers to the
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Uncalcified cemental matrix
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9
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Connective tissue fibers embedded in to the
cementum are known as |
Sharpey’s fibers.
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10
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What are Kroff’s fibers
|
They are an imaginary fibers associated with
dentin caused by the silver staining of ground substances. |
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11
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Acellular cementum is not present at
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Apical third of root. At the apical third of
root cementum is entirely cellular type. Recent investigations point out that the classification of cementum based on cellular elements is biased. There seems to be an entirely different genotype and phenotype of cementoblasts responsible for secretion of these two types of cementum. |
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12
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Cementum is thinnest at the
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Cemento enamel junction. It is about 20 to
50 micrometer at the cementoenamel junction. |
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13
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The maximum thickness of cementum is
approximately |
150 to 200 micrometers
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14
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Cementum is thickest at the
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Apex
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15
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Uncalcified cementum is seen to be deposited
in the |
Cementodentinal junction. Though there is a
layer of uncalcified cementum on the entire cementum it is in its developmental process. Uncalcified cementum is seen along the cementodentinal junction. |
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16
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The processes of a cementocyte are generally
directed to the |
Periodontal surface
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17
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Incremental lines of cementum are
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Hypermineralized areas
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18
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A permanent human cementodentinal junction
is |
Relatively smooth
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19
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Intermediate cementum is found in between
|
Dentin and cementum
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20
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Intermediate cementum is commonly observed
in apical two thirds of |
Permanent premolars and molars
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21
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Intermediate cementum is the area
representing |
Entrapped Hertwig’s epithelial sheath
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22
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Cementum and enamel do not meet in
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10% of all teeth
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23
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An overlap of cementum on cervical end of
enamel occurs due to |
Premature loss of reduced enamel epithelium
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24
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When cementoblasts meet the smooth surfaces
of enamel it produces |
Afibrillar cementum
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25
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Total absence of cementum can be observed in
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Hypophosphatasia
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26
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The function of cementum does NOT include
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Self -resorption under normal condition
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27
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Loss of tooth substance from occlusal wear
is compensated by increase in |
Cementum at apex
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28
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Cemental hypertrophy is accompanied by
|
Increase in functional quality
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29
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In cementum hypertrophy spur can be formed
in teeth that are |
Exposed to great stress
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30
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Knob like projections of hyperplastic
cementum is referred as |
Excementoses
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31
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Extensive hyperplasia of cementum is
occasionally associated with |
Chronic periapical inflammation
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32
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Hyperplasia of cementum in nonfunctioning
teeth is characterized by |
A reduction in number of Sharpey’s fibers
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33
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Cementum differs from bone because bone is
|
Vascular
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34
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A tendency of cementum to reestablish the
former outline of root surface is termed as |
Anatomic repair
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35
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When the alveolar bone is modified to suit
the functional relationship of a damaged cementum the repair is said to be |
Functional repair
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36
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Afibrillar cementum is found at the
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Cervical margin of the tooth
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37
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Coronal cementum is a type of
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Afibrillar cementum
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38
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Incremental lines seen in cementum are
referred to as |
Incremental lines of Slater
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39
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The structureless, highly mineralized layer
that is about 10 micrometers thick on the surface of root dentin is |
Hyaline layer of Hopewell Smith. It is atubular
structure with a unique organic matrix and is more mineralized than cementum or dentin. It is believed to be the tissue that cements the cementum to the dentin. |
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40
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The first formed collagen fibrils by the
cementoblasts are deposited _________ to the root surface. |
In angular fashion
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41
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The first formed cementum is
|
Acellular type. As the cells forming the
first formed cementum does not incorporate the cementoblasts it self and instead found on the surface the first formed cementum is acellular. |
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42
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The function of acellular cementum is to
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Provide attachment for tooth. Though all the
functions described are functions of cementum, the acellular cementum maintains the anchorage part of the function and rest are performed by the cellular cementum. |
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43
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Cementum is classified on the basis of
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Time of formation; Presence of cells within
the matrix; Origin of collagen fibers. Cementum can be classified on the basis of time of formation (primary or secondary), by the presence of cells within the matrix (cellular or acellular) and origin of collagen fibers (intrinsic or extrinsic) |
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44
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The cementum that is formed before the
periodontal ligament formation is |
Primary acellular intrinsic fiber cementum.
Explanation Secondary cementum formation occurs after teeth eruption. Primary acellular extrinsic fiber cementum arises from the periodontal ligament only. |
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45
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The principal tissue of attachment of the
cementum is the |
Primary acellular extrinsic fiber cementum
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46
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In some of anterior teeth the only form of
cementum found is the |
Primary acellular extrinsic fiber cementum
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47
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The degree of mineralization of the primary
acellular extrinsic fiber cementum is about |
60%
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48
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The form of cementum that is always absent
in anterior teeth is the |
Secondary cellular intrinsic fiber cementum.
It is found only in the inter-radicular region and rarely only in apical regions. |
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49
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The bulk of the secondary cementum is made
up by the |
Secondary cellular mixed fiber cementum
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50
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The intrinsic fibers of the cementum are
arranged ________ to the root surface. |
Parallel. These are fine fibered, densely
packed fibers running parallel to the root surface whereas the extrinsic fibers are larger, haphazardly running and is oriented to root surfaces perpendicularly. |
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51
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A cementum that is a developmental anomaly
is |
Acellular afibrillar cementum. It is limited
to enamel surface as spurs close to cementoenamel junction and formed as a result of local disruption of reduced enamel epithelium. |
Prof. Rooban Thavarajah
Oral and Maxillofacial Pathologist
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