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Question
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Answer
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1
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The components of periodontium
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Alveolar bone; Periodontal ligament; Cementum; Gingiva. Of these
calcified tissues are the cementum and alveolar bone. The fibrous connective tissues are the periodontal ligament and the lamina propria of the gingiva. |
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2
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The periodontium is attached to
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Dentin; Jaw bone; Lamina propria of gingiva
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3
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The majority of fibers of periodontal ligament are made up
of |
Collagen
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4
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The epithelium component in the periodontium is
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Cell rests of Malassez
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5
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The periodontal ligament occupies the space between
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Cementum and alveolar bone. Hence this space is called the
periodontal ligament space |
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6
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Perifollicular mesenchyme cells are the cells that surround
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Dental follicle. They give rise to Cementoblast, Osteoblast,
Fibroblast |
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7
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Epithelial cell rests of Malassez are strands of
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Hertwig’s root sheath
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8
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The principal cell of the periodontal ligament is
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Differentiated mesenchymal cell
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9
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The osteoblasts covering the periodontal surface of alveolar
bone are |
Modified endosteum
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10
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A periosteum is made up of
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Inner cambium and outer fibrous layer
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11
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The bone lining dental socket is regarded as
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Interior surface of bone
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12
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The precursor cells of osteoclasts are
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Circulating monocytes
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13
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In the osteoclasts occupy resorption bay, the adjacent plasma
membrane is known as |
Ruffled border
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14
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The parts of the active osteoclast that lie adjacent to the bone
have a |
Striated border. Also called as ruffled border, they increase
the surface area of the osteoclasts so that they can function efficiently. |
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15
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Osteoclasts are rich in
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Acid phosphatase. In order to cause the bone resorption an
excess of this enzyme is needed. |
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16
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Collagen synthesis in periodontal ligament is the function
of |
Fibroblast
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17
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Collagen degradation in periodontal ligament is the function
of |
Fibroblast
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18
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The cell junction most commonly observed between cells of
periodontal ligament is |
Gap junctions
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19
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The majority of fibers of periodontal ligament are
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Collagen
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20
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The majority of types of collagen in periodontal fibers are
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Type I and III
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21
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Collagen macromolecules are rod like and arranged to form
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Fibrils
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22
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Light microscopy can visualize collagen fibers of diameter
above |
0.2 micrometers
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23
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The most superficial fibers of periodontal ligament are the
fibers of the |
Alveolar crest group
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24
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The most numerous periodontal ligament fibers are the
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Oblique group
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25
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Coronal insertion of the oblique fibers of the periodontal
ligament is in |
Alveolar bone
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26
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The principle fibers of periodontal ligament frequently have
a |
Wavy course
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27
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Elastic fibers of periodontal ligament are generally restricted
to |
Blood vessels
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28
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The oxytalan fibers of periodontal ligament tend to run
from |
Axial direction
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29
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The oxytalan fibers form a complex network at
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Apex
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30
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In the periodontal ligament the oxytalan fibers
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Extends from superficial cementum apically to terminate in
association with blood vessels & nerves |
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31
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Periodontal ligament does not contain
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Mature Elastic fibers. It contains collagen, Oxytalan &
elaunin and Immature elastic fibers. |
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32
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Glycoprotein’s can be demonstrated in light microscopy by
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Periodic acid –Schiff method
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33
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Fibronectin is a
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Glycoprotein
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34
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The arterial supply of periodontal ligament is derived from
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Branches of apical vessels; Branches of intra-alveolar vessels;
Branches of gingival vessels |
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35
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The blood capillaries in the periodontal ligament are more
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Nearer to bone. The blood capillaries in the periodontal
ligament are nearer to bone and numerous in the apex and the cervical part of the ligament. |
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36
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The lymphatic flow in periodontal ligament is from the
periodontal ligament to the |
Alveolar bone
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37
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The fastest turnover rate of collagen in all the connective
tissue is seen with |
Periodontal ligament
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38
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Calcified bodies seen in periodontal ligament fibers are known
as |
Cementicles
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39
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When cementicles are attached to cementum it is referred as
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Excementoses
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40
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Periodontal ligament varies in width from
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0.15-0.38 millimeters
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41
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Periodontal ligament is thinnest at
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Middle third of the root
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42
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As compared to tooth in function, periodontal ligament in non
functional tooth is |
Thicker
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43
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The thickness of periodontal ligament in an embedded tooth
is |
Thin
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44
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The thickness of periodontium is maintained by
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Functional remodeling
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45
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The periodontal ligament increases in thickness in
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Excessive occlusal stresses.
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46
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The thin periodontal ligament at the middle third of root
indicates that |
Fulcrum of physiologic movement lies here
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47
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Occlusal trauma is always restricted to
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Intra-alveolar tissues
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48
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Orthodontic tooth movement relies on fact that there is possible
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Resorption of alveolar bone; Formation of alveolar bone;
Remodeling of periodontal ligament fibers |
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49
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The stimulus provided by the orthodontic treatment is
transmitted by the |
Periodontal ligament
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50
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Fibronexus involves
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Intracellular filaments; Dense cell membrane; Sticky attachment
glycoprotein fibronectin |
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51
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Fibroblasts are motile because of the action of
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Actin
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52
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Sharpey’s fibers are fully mineralized in
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Acellular cementum
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53
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Perforating arteries are more in
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Periodontal ligament of posterior teeth
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54
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The principal fiber of the periodontal ligament which extends
from tooth to tooth is |
Transseptal group
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55
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The initial attachment of periodontal ligament during
odontogenesis is modified by |
Pre-eruptive tooth movements; Eruptive tooth movements;
Adjustment of occlusion |
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56
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The fibers of periodontal ligament attain their maximum
thickness with |
Function. When the tooth comes in to function, the periodontal
ligament fiber bundles attain their maximum thickness. Also in the age group of 11 -18 years, the thickness is the highest. |
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57
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Root planning or removal of damaged cementum heals by a false
attachment because of the absence of |
Hyalin layer of Hopewell Smith. When this layer is removed
during root planning then the healing and the attachment is not perfect. |
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58
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The anatomical location of undifferentiated mesenchymal cells in
periodontal ligament fiber is at |
Perivascular region. The undifferentiated mesenchymal cells are
situated within 5 micrometers of the blood vessels. |
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59
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The base of the socket is
formed by the fibers of periodontal ligament belonging to |
Apical group
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60
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The fibers of the periodontal ligament that is associated with
the neural elements are the |
Oxytalan
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61
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The principal constituent of the glycosaminoglyans in PDL is the
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Dermatan sulfate
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62
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In maxillary central incisors, in the periodontal ligament,
numerous neural elements exist in the |
Coronal half of the labial periodontal ligament. In all other
tooth neural elements are seen in large numbers in the apical region and in the labial or buccal side. |
Prof. Rooban Thavarajah
Oral and Maxillofacial Pathologist
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