Histology: Early Tooth Development

Front 1

Which develops first, the crown of a tooth or the root?

Back 1

crown develops before root

Front 2

The enamel organ portion of a tooth is derived from what?

Back 2

modified oral epithelium

Front 3

Ectomesenchyme is derived from _________ _________ _______ and forms the dentin and pulp of both crown and root.

Back 3

neural crest cells

Front 4

What are the main stages of the life cycle of a tooth?

Back 4

1. Growth
2. Calcification
3. Eruption
4. Attrition

Front 5

What are the 5 stages of growth in the life cycle of a tooth?

Back 5

1. initiation
2. proliferation
3. morphodifferentiation
4. histodifferentiation
5. appositional growth

Front 6

"oral epithelium" is gingiva prior to what?

Back 6

the presence of teeth

Front 7

The dental lamina stage and the dental bud stage are part of which stage of odontogeneiss?

Back 7

initiation

Front 8

The first sign of tooth development; 6th week in utero; horse-shoe shaped

Back 8

formation of the dental lamina

Front 9

along 10 specific points on the the mandible and maxilla arch the oral epithelium grows downwards into ectomesenchyme; becomes bulbous and looks like a boot

Back 9

dental bud stage; formation of tooth bud

Front 10

formation fo the dental cap is a part of which stage of odontogenesis?

Back 10

proliferation

Front 11

during the formation of the tooth bud mitosis on the superior surface and distal tip form concavity which is filled in by ____________ and represents the future dental papilla.

Back 11

ectomesenchyme

Front 12

during the _______ __________, molecule control of the shaping of the tooth is passed from epithelium to ectomesenchyme.

Back 12

cap stage

Front 13

What are the three layers of the enamel organ associated with the cap stage?

Back 13

1. outer enamel epithelium
2. inner enamel epithelium
3. stellate reticulum

Front 14

junction where outer and inner enamel epithelium come together; involved in root formation

Back 14

cervical loop

Front 15

single layer of cuboidal cells along cap convexity (sides of cap)

Back 15

outer enamel epithelium

Front 16

single layer of columnar epithelial cells along cap concavity (bottom of cap)

Back 16

inner enamel epithelium

Front 17

What is the stellate reticulum composed of?

Back 17

stellate shaped cells separated by glycosaminoglycans

Front 18

What is dental papilla?

Back 18

ectomesenchyme in concavity underneath the inner enamel epithelium

Front 19

What is the dental sac?

Back 19

loosely organized ectomesenchyme that surrounds developing enamel organ and which will form the cementum, PDL and alveola

Front 20

Dental bell formation is a part of which stage of odontogenesis?

Back 20

morphodifferentiation and histodifferentiation

Front 21

morphodifferentiation refers to the determination of the ________ of the tooth

Back 21

shape

Front 22

histodifferentiation refers to the differentiation of the ameloblasts from the ________ enamel epithelium and the odontoblasts from the ___________ __________.

Back 22

inner; dental papilla

Front 23

Shape of the tooth is determined by the ectomesenchyme of the __________ _________ with the molecular events occuring during the _____ stage and the structural changes occurring during the _____ stage.

Back 23

dental papilla; cap stage; bell

Front 24

differentiation always begins at the _________ _____ and moves cervically

Back 24

cuspal tip

Front 25

ameloblasts are the cells that form___________.

Back 25

enamel

Front 26

the columnar cells of the inner enamel epithelium form ____________

Back 26

ameloblasts

Front 27

forms complexes around blood vessels and degenerate to form gaps

Back 27

outer enamel epithelium

Front 28

2 to 3 cell layers on the surface of the inner enamel epithelium; the nutritional layer essential for the formation of enamel by ameloblasts

Back 28

stratum intermedium

Front 29

During the bell stage, the __________ __________ continues to secrete GAGs to facilitate the growth of the crown.

Back 29

stellate reticulum

Front 30

What two dental tissues develop from the dental lamina?

Back 30

dental pulp and dentin (odontoblasts)

Front 31

What is the last layer of the enamel organ to develop?

Back 31

stratum intermedium; forms on surface of inner enamel epithelium; required for ameloblasts to secrete enamel

Front 32

involved in the formation of the root after the crown has formed

Back 32

cervical loop

Front 33

the thickening of oral epithelium lateral to the dental lamina; cells grow downward into CT and degenerate in center forming a cavity

Back 33

vestibular lamina

Front 34

successional lamina is found ________ to the tooth

Back 34

medial

Front 35

The extension of dental lamina lingual to the tooth; forms 20 of the permanent teeth

Back 35

successional lamina

Front 36

remains of the original dental lamina

Back 36

parent dental lamina

Front 37

connects developing primary tooth to parent lamina

Back 37

lateral lamina

Front 38

the lamina for permanent molars is derived from distal portion of dental lamina without a ________ ________ _________.

Back 38

primary tooth precursor

Front 39

In the ________ stage, the enamel organ loses contact with the oral epithelium and the _________ lamina degenerates.

Back 39

bell; parent lamina degenerates

Front 40

What are epithelial rests?

Back 40

islands of epithelium surrounded by CT that form from the breakdown of epithelial tissue and form supernumerary teeth, tumors, cysts, etc.

Front 41

when epithelial rests are found in the gingival CT they are referred to as what?

Back 41

Rests of Serres

Front 42

If rests of Serres are calcified then they are called what?

Back 42

Pearls of Serres

Front 43

Rests of Serres are analogous to the rests in the PDL which go by which name?

Back 43

Rests of Malassez; when calcified in PDL called cementicle instead of pearl