C1 Anatomy of the Periodontium

Question 1

Oral mucosa consists of the following three zones:

Answer 1

1. Masticatory mucosa (gingiva + covering of the hard palate)
2. Specialized mucosa (dorsum of the tongue)
3. Oral mucous membrane lining the remainder of the oral cavity

Question 2

The gingiva is anatomically divided into:

Answer 2

1. Marginal gingiva
2. attached gingiva
3. interdental gingiva

Question 3

Terminal edge or border of the gingiva that surrounds the teeth in collarlike fashion

Answer 3

Marginal or unattached gingiva

Question 4

Demarcates the marginal gingiva from the attached gingiva

Answer 4

Free gingival groove

Question 5

What do you call the most apical point of the marginal gingival scallop

Answer 5

gingival zenith

Question 6

It is the shallow crevice or space around the tooth bounded by the surface of the tooth on one side and the epithelium lining the free margin of the gingiva on the other side

Answer 6

Gingival sulcus

Question 7

T/F The histologic depth of a sulcus is exactly equal to the depth of penetration of the probe.

Answer 7

F. affected by different factors such as diameter, probing force, and level of inflammation

Question 8

Normal probing depth of a clinically normal gingival sulcus in humans

Answer 8

2-3mm

Question 9

Describe the attached gingiva

Answer 9

Firm, resilient and tightly bound to the underlying periosteum of alveolar bone

Question 10

Demarcates the attached gingiva and the relatively loose and movable alveolar mucosa

Answer 10

Mucogingival junction

Question 11

Where is the width of the attached gingiva a.) widest? b.) narrowest?

Answer 11

Generally greatest in the incisor region and narrower in the posterior segments

Question 12

T/F Mucogingival junction remains stationary throughout adult life

Answer 12

True. Changes in the width of the attached gingiva are caused by modifications in the position of its coronal portion

Question 13

What is “col” in the interdental gingiva?

Answer 13

It is a valleylike depression that connects a facial and lingual papilla

Question 14

microscopic features of the gingiva

Answer 14

Composed of overlying stratified squamous epithelium and the underlying connective tissue. CT composed of primarily collagen fibers and ground substance

Question 15

Microscopic feature of col

Answer 15

Nonkeratinized stratified squamous epithelium

Question 16

Three different areas of gingival epithelium that can be defined from the morphologic and functional points of view

Answer 16

1. oral epithelium (parakeratinized/keratinized stratified squamous)
2. sulcular epithelium (nonkeratinized stratified squamous)
3. junctional epithelium (nonkeratinized stratified squamous)

Question 17

What is the primary cell type of the gingival epithelium

Answer 17

Keratinocytes.

Langerhans cells, merkel cells, and melanocytes can also be found.

Question 18

Dendritic cells located in the basal and spinous layers of the gingival epithelium

Answer 18

Melanocytes

Question 19

Dendritic cells located among keratinocytes at all suprabasal levels

Answer 19

Langerhans cells (modified monocytes from the bone marrow)

Question 20

Tactile perceptors located in the deeper layers of the epithelium which harbor nerve endings. They are connected to the adjacent cells by desmosomes.

Answer 20

Merkel cells.

Question 21

Where is the oral epithelium located

Answer 21

Covers the crest and outer surface of the marginal gingiva and the surface of the attached gingiva

Question 22

Prevalent surface of Oral epithelium

Answer 22

Parakeratinized. however, it can be keratinized or combination of both.

Question 23

Lines the gingival sulcus

Answer 23

sulcular epithelium

Question 24

Location, Lining, and permeability of sulcular epithelium

Answer 24

Extends from the coronal limit of the junctional epithelium to the crest of the gingival margin
Nonkeratinized stratified squamous without rete pegs.
** despite this, it can keratinize if exposed to the oral cavity
Semipermeable membrane through which bacterial products pass into the gingiva and through which tissue fluid from the gingiva seeps into the sulcus

Question 25

Attaches the Junctional epithelium to the tooth surface

Answer 25

Internal basal lamina

Question 26

T/F The junctional epithelium is a continually self-renewing structure

Answer 26

True. It has mitotic activity occurring in all cell layers.

Question 27

How does junctional epithelium contribute in preventing pathogenic bacterial flora from colonizing the subgingival tooth surface

Answer 27

1. JE firmly attached to the tooth surface (barrier)
2. JE allows access of gingival fluid, inflammatory cells, and components of the immunologic host defense to the gingival margin.
3. JE exhibits rapid turnover –> contributes host-parasite equilibrium ad rapid repair of damaged tissue

Question 28

Function of gingival fluid/sulcular fluid

Answer 28

1. cleanse material from the sulcus
2. contain plasma proteins –> improve adhesion of the epithelium to the tooth
3. possess antimicrobial properties
4. exert antibody activity to defend the gingiva

Question 29

During inflammation, gingival fluid ______

Answer 29

increases.

in the healthy sulcus, GF is minimal/very small.

Question 30

Functions of gingival fibers

Answer 30

1. to brace the marginal gingiva firmly against the tooth
2. provide rigidity –> to withstand forces of mastication
3. to unite free marginal gingiva with the cementum of the root and the adjacent attached gingiva

Question 31

Describe the different gingival fibers

Answer 31

1. gingivodental/dento-gingival fibers - fanlke conformation from the cementum to the crest of marginal gingiva and outer surface
2. circular fibers - CT of marginal and interdental gingiva; encircles the tooth
3. transseptal fibers - located interproximally between teeth
4. dentoperiostal - cementum to periosteum of the bone
5. alveologingival - alveolar bone to the gingiva

Question 32

Blood supply to the gingiva

Answer 32

1. supraperiosteal arterioles
2. vessels of the periodontal ligament
3. arterioles from the crest of the interdental septa

Question 33

factors affecting color of gingiva

Answer 33

vascular supply, degree of keratinization, presence of pigment-containing cells

Question 34

factors affecting size and shape of gingiva

Answer 34

location and size of proximal contact, shape and alignment of teeth. dimensions of gingival embrasure, contour of proximal tooth surfaces

Question 35

what determines the firmness consistency of the gingiva

Answer 35

collagenous nature of the lamina propria and its contiguity with the mucoperiosteum of the alveolar bone