Enamel And Its Significance In The Study Of Cariology

Question 1

An acellular, avascular, and highly mineralized material that covers the anatomic crown of a tooth.

Answer 1

Enamel

Question 2

Thickness of the enamel at the incisal edges of incisors

Answer 2

2mm

Question 3

The enamel gets progressively thinner towards the CEJ.

Answer 3

False

Question 4

A hard, stiff, and wear resistant tissue.

Answer 4

Enamel

Question 5

The 96% inorganic material in the enamel.

Answer 5

Hydroxyapatite

Question 6

Development of the dental lamina from the oral epithelium.

Answer 6

Initiation stage

Question 7

Proliferation of the dental lamina into ectomesenchyme.

Answer 7

Bud stage

Question 8

Proliferation and differentiation to form the tooth germ.

Answer 8

Cap stage

Question 9

The innermost margin of the cap shape of the enamel organ forms the future crown form of the tooth, such as cusps.

Answer 9

Enamel knots

Question 10

Differentiation of the enamel organ and dental papilla into different layers.

Answer 10

Bell stage

Question 11

Differentiation of preameloblast to ameloblasts and beginning of amelogenesis from Tomes process.

Answer 11

Apposition stage

Question 12

Not a true process, and is the projection of the secretiry end of each ameloblast that faces the DEJ

Answer 12

Tomes process

Question 13

Fuses with the oral epithelium then degenerates.

Answer 13

Reduced Enamel Epithelium (REE)

Question 14

Green-gray residue of the fused tissue of the REE and oral epithelium.

Answer 14

Nasmyth membrane/Primary enamel cuticle

Question 15

The 4 lobes of the anterior teeth.

Answer 15

Medial, labial, distal, lingual

Question 16

Deep invaination of the enamel surface, resulting from failure of the developmental lobes to coalesce.

Answer 16

Fissures

Question 17

Non-coalesced enamel at the deepest point of a fossa

Answer 17

Pits

Question 18

Fundamental crystalline organizational unit of enamel

Answer 18

Enamel rods

Question 19

The enamel rods are prismatic in cross-section but become irregular once fully matured

Answer 19

True

Question 20

Structural components of enamel rods that are millions of small and vary in size and shape

Answer 20

Apatite crystallites

Question 21

Organically rich interspace

Answer 21

Rod sheath

Question 22

Pit and Fissure caries appears smaller than assumed at the surface

Answer 22

False

Question 23

Occurs near the cervical regions and incisal and occlusal areas, and is not subject to fracture as much as regular enamel.

Answer 23

Gnarled enamel

Question 24

Alternate light and dark zones of varying widths that have slightly different permeability and organic content.

Answer 24

Hunter-Schreger Bands

Question 25

Hypomineralized enamel structures of the enamel rods and interrod substance that project between adjacent groups of rods from teh DEJ

Answer 25

Enamel tufts

Question 26

Odontoblasts that crossed the basement membrane before it mineralized into the DEJ

Answer 26

Enamel spindles

Question 27

Thin, leaf-like faults between enamel rod groups that extend from the enamel surface to the DEJ, sometimes into dentin.

Answer 27

Enamel lamellae

Question 28

The enamel lamellae contain mostly inorganic material.

Answer 28

False

Question 29

Series of alternating grooves formed when striae of Retzius circles are incomplete at the enamel surface

Answer 29

Imbrication lines of Pickerill

Question 30

Elevations between the grooves, usually continuous around a tooth and usually lie parallel to the CEJ and each other.

Answer 30

Perikymata

Question 31

The interface of enamel and dentin.

Answer 31

Dentinoenamel Junction

Question 32

Outline of the DEJ

Answer 32

scalloped or wavy

Question 33

The enamel hardness and density decreases towards the DEJ.

Answer 33

True

Question 34

Teeth have very thin enamel that chips off or have no enamel at all, and there are yellow crowns due to exposed dentin.

Answer 34

Amelogenesis imperfecta

Question 35

Type of Amelogenesis Imperfecta with defective matrix formation and the enamel is not formed to full normal thickness.

Answer 35

Type I: Hypoplastic Amelogenesis Imperfecta

Question 36

Reduction in quantity of enamel matrix; pitting and grooves on the enamel surface.

Answer 36

Enamel hypoplasia

Question 37

Type of Amelogenesis Imperfecta wherein the enamel crystallites remain immature, normal thickness. The defective enamel can be chipped away from the dentin matrix using an instrument under firm pressure.

Answer 37

Type II: Hypomature Amelogenesis Imperfecta

Question 38

Reduction in the quality of the enamel maturation; opaque, yellower, or even browner due to intrinsic staining.

Answer 38

Enamel hypocalcification

Question 39

Caused by excessive systemic fluoride during enamel matrix formation and calcification

Answer 39

Fluorosis

Question 40

Pit and fissure take up the configuration following the direction of enamel rods wherein the broader base is oriented towards the enamel surface

Answer 40

True

Question 41

Gnarled enamel appears as concentric circles in enamel due to the incremental formation of the enamel

Answer 41

False