PDL

Question 1

The PDL fibers running between two adjacent teeth:
a- Belong to the dento-alveolar group.
b-Are gingival fibers.
c- Are transseptal fibers.
       d- Are oxytalan fibers.

Answer 1

C

Question 2

Which of the following is not true of the alveolodental periodontal fibers? They:
a- Are organized into bundles with different orientation.
b- Are derived from epithelial rests of Malassez.
c- Undergo continuous remodeling.
d- Are formed and partially resorbed by fibroblasts.

Answer 2

B

Question 3

Which of the following is not present in the periodontal ligament?
a- Epithelial rests of Malassez.
b- Fibroblasts.
c- Cementoblasts.
d- Osteocytes.

Answer 3

D

Question 4

Which of the following principal fibers groups constitutes the main attachment of the tooth?
a- Oblique group.
b- Apical group.
c- Horizontal group.
d- Alveolar group.

Answer 4

A

Question 5

Which groups of tissues comprise the periodontium?

Answer 5

Cementum, alveolar bone, periodontal ligament, gingiva.

Question 6

The width of the periodontal ligament:
a- It is thiner when teeth are functioning normally.
b- It is narrowest at the level of the midroot area.
c- It becomes wider with aging.
d- It is of uniform width around multi-rooted teeth.

Answer 6

B

Question 7

The periodontal ligament develops from what?

Answer 7

The dental sac

Question 8

Elasticity of periodontal ligament is due to what?

Answer 8

Wavy coarse of collagen fibers.

Question 9

The principal fibre of periodontal ligament is what?

Answer 9

collagen

Question 10

Function of oxytalan fibers:
a- Support nerves. b- Support blood vessels.
c- Help fibroblasts migration. d- All of the above.

Answer 10

D

Question 11

Open faced nucleus is found in:
a- Resorptive cells. b- Synthetic cells.
c- Defensive cells. d- Progenitor cells.

Answer 11

B

Question 12

The periodontal ligament is formed of:
a- Cells only. b- Fibers only.
c- Ground substances only. d- All of the above

Answer 12

D

Question 13

The protective function of periodontal ligament is achieved by its:
a- Fibers. b- Blood vessels.
c- Nerves. d- All of the above.

Answer 13

D

Question 14

The periodontal ligament
a, Derives its blood supply primarily from the branches of vessels entering the pulp
b. Has a slow rate of turn over
c. Contains epithelial cells
d. Comprises primarily of type II collagen

Answer 14

C

Question 15

Collagen molecule exhibits all of the following features except:
A. Triple pleated sheath
B Mostly contains glycine residues
C. Exhibit cross striations at 64 μm
D. Intracellular in nature

Answer 15

D

Question 16

Remnants of the Hertwig’s root sheath are found in:
A. Gingiva
B. Alveolar bone
C. Periodontal ligament
D. Cementum

Answer 16

C

Question 17

All of the following cells of periodontal ligament are of mesenchymal origin except:

A. Fibroblasts
B. Multi totipotent cells
C. Cementoblasts
D. Cell rests of malassez

Answer 17

D

Question 18

The attached apparatus of tooth is composed of:
A. Gingiva, cementum and alveolar bone
B. Gingiva and cementum
C. Cementum and periodontal ligament
D. Peridontal ligament the cementum and the alveolar bone

Answer 18

D

Question 19

The vascular supply of the periodontal ligament is:
A. Greatest in the middle-third of a multirooted tooth
B. A net like plexus that runs closer to the cementum than to the bone
C. A net like plexus that runs closer to the bone than to the cementum
D. Greatest in the middle-third of a single rotted tooth

Answer 19

C

Question 20

Fibres of periodontal ligament embedded in the bone are:
A. Sharpey's fibres
B. Tomes fibres
C. Elastic fibres
D. Ray's fibres

Answer 20

A

Question 21

Group of fibres, which resist the masticatory forces
A. Dentogingival
B. Transeptal
C. Oblique
D. Horizontal

Answer 21

C

Question 22

Intermediate plexus is seen in the:
A.  Cementum
B. PDL
C. Pulp
D. Dentin

Answer 22

B

Question 23

In mammals independent and tough suspension for teeth is provided by:
A. Alveolar sockets
B. Cementum
C. Gubernacular cords
D. Periodontal membrane

Answer 23

D

Question 24

Bone adjacent to periodontal ligament that contains a great number of sharpey’s fibres is known B. Bundle bone
C. Lamina
D. Lamina densa

Answer 24

B

Question 25

``` The most abundant principle fibre group in periodontal A. Horizontal B. Transeptal C. Apical D. Oblique ```

Answer 25

D

Question 26

``` Collagen biosynthesis occurs inside the: A. Chondroblasts B. Odontoblasts C. Osteoblasts D. Fibroblasts ```

Answer 26

D

Question 27

``` Which of the following groups of fibres are not attached to alveolar bone? A. Transseptal B. Horizontal C. Oblique d. Apical ```

Answer 27

A

Question 28

``` Principal fibres of periodontal ligament are attached to: A. Alveolar bone proper B. Bundle bone C. Lamellar bone D. Cortical bone ```

Answer 28

B

Question 29

``` The calcified mass found in the PDL are: A. Cementicles B. Osteoblasts C. Cementoclasts D. Osteoclasts ```

Answer 29

A

Question 30

``` Sharpey’s fibres are derived from: A. Hertwig's root sheath B. Epithelial rests of malassez C. Alveolar bone D. Dental follicle ```

Answer 30

D

Question 31

``` Sharpey’s fibres are present in: A. Bone B. Periosteum C. Periodontal ligament D. All of the abov ```

Answer 31

A

Question 32

Interdependency of osteoblasts and osteoclasts in bone remodeling is called as: Lacunae Coupling Reversal lines Canaliculi

Answer 32

B

Question 33

True about osteoclasts A. Monocytes are precursor cells of osteoclasts B. The plasma membrane of osteoclasts adjacent to bone that is being resorbed is known as striated or ruffled border C. Contain lysosomes with acid phosphates D. All of the above are true

Answer 33

D

Question 34

Which of the following is correct A, Fibronectin helps in attachment of fibroblasts to collagen B. Cementicles are found in periodontal ligament of order individuals C. The large nerve fibres are myelinated and are concerned with discerment of touch D. The small nerve fibres may or may not be myelinated and are concerned with discrement of pain E. All of the above

Answer 34

E

Question 35

``` Cementicles are found in the; A. Gingiva B. Periodontal ligament C. Alveolar bone D. Cementum ```

Answer 35

B

Question 36

``` The rest of malassez in the periodontal ligament are derived from A. Dental pulp B. Lamina propria C. Odontogenic epithelium D. Vestibular lamina ```

Answer 36

C

Question 37

``` Development of supporting tissues of the tooth is initiated by: A. Cells of dental follicle B. Cells of odontogenic layer C. Cementoblasts D. Cells of the gingiva ```

Answer 37

A

Question 38

``` The main function of horizontal fibres of P.D ligament is: A. Prevent extrusion B. Prevent rotation C. Maintains the mesiodistal width D. All of the above ```

Answer 38

C

Question 39

The periodontal ligament is approximately a. 0.25 mm in thickness b. 0.5 mm in thickness c. 0.75 mm in thickness d. 1.0 mm in thickness

Answer 39

A

Question 40

``` The component of future T.M.J shows development at? A. 6 weeks B. 10 weeks C. 18 weeks D. 16 weeks ```

Answer 40

B