Odontogenesis- EXAM I Flashcards
1
Q
What four components make up the tooth?
A
Enamel, dentin, cementum & pulp
2
Q
What four components make up the periodontium?
A
Gingiva, periodontal ligament, cementum, alveolar bone proper
3
Q
List the six stages of tooth development:
A
- Initiation
- Bud stage
- Cap stage
- Bell stage
- Apposition
- Maturation
4
Q
During the initiation stage of tooth development what occurs?
A
Cellular induction
5
Q
During the bud stage of tooth development what occurs?
A
Cellular proliferation
6
Q
During the cap stage of tooth development what occurs?
A
Proliferation, differentiation & morphogenesis
7
Q
During the bell stage of tooth development what occurs?
A
Proliferation, differentiation & morphogenesis
8
Q
During the apposition stage of tooth development what occurs?
A
Induction & proliferation
9
Q
During the maturation stage of tooth development what occurs?
A
Maturation
10
Q
Plays an instructional role during the pre-tooth bud stage of tooth formation
A
Epithelium (Ectoderm)
11
Q
What dictates what type of tooth will be formed?
A
Neural crest cells (mesenchyme)
12
Q
The enamel organ is derived from:
A
Primitive oral ectoderm
13
Q
What three structures are prominent during the induction stage of tooth development:
A
- Oral ectoderm
- Neural crest cells
- Dental lamina
14
Q
When does the induction stage of tooth development occur?
A
6th-7th week
15
Q
During the induction stage when the ectoderm invaginates into the mesenchyme it can now be referred to as:
A
Dental lamina
16
Q
The dental lamina is separated from the surrounding mesenchyme by a:
A
Basement membrane
17
Q
When does the bud stage of tooth development occur?
A
8th week
18
Q
During the bud stage of tooth development the proliferating oral ectoderm makes the transition into:
A
Dental lamina
19
Q
When does the early cap stage of tooth development take place?
A
9th to 10th week
20
Q
During the early cap stage, ______ occurs resulting in the creation of buccal vestibule
A
Apoptosis
21
Q
Help to hold the shape of the enamel organ during the cap stage of tooth development
A
Stellate reticulum
22
Q
Cells that are still undifferentiated but make their way up into the inner enamel epithelium area
A
Dental papilla
23
Q
Some of the dental papilla cells will end up becoming:
A
Odontoblasts & pulp
24
Q
During the cap stage of tooth development what surrounds the enamel organ, inner enamel epithelium & dental papilla
A
Dental follicle
25
The dental follicle may also be called the:
Dental sac
26
The dental follicle encapsulates the entire enamel organ & will eventually become the:
Periodontal ligament, cementum, & alveolar bone
27
At this stage, all layers of the enamel organ can be differentiated:
Bell stage
28
During the bell stage, the inside of the enamel organ is comprised of:
Inner enamel epithelium
29
During the bell stage, the enamel organ is covered by _____ on the outside
Outter enamel epithelium
30
The double layer of flattened cells on top of the inner enamel epithelium during the bell stage of developement:
Stratum intermedium
31
During the bell stage, the loosely packed cells on the inside of the stratum intermedium:
Stellate reticulum
32
The rounded cells lining the basement membrane, during the bell stage of tooth development:
Pre-odontoblasts
33
The outer enamel epithelium is comprised of _____ cells & serves as _____
Cuboidal cells
Protective barrier
34
The inner enamel epithelium is comprised of ____ cells & differentiates into _____
Cuboidal cells
Ameloblasts
35
The stellate reticulum are ____ shaped ells forming the network inside the ______
Star-shaped
Enamel organ
36
What serves as the supportive function in enamel production:
Stellate reticulum & Stratum intermedium
37
The stratum intermedium is a compressed layer of:
Flat cuboidal cells
38
The dental sac consists of _____ fibers around the _____
Collagen
Enamel organ
39
What will the dental sac eventually differentiate into?
1. Cementum
2. PDL
3. Alveolar bone
40
The cells nearest to the IEE that have basement membrane separation:
Dental papilla
41
The outter cells of the dental papilla differentiate into:
Odontoblasts
42
The inner cells of the dental papilla differentiate into:
Pulp tissue
43
During the bell stage of tooth development- at the bottom where the inner & outer epithelium meet form the:
Cervical loop
44
During root development, the junction of the outer & inner enamel epithelia:
Cervical loop
45
The cervical loop is the site of _____ in the adult tooth
Cemento-enamel junction (CEJ)
46
Fusion of the apical extension of the outer & inner enamel epithelia:
Hertwig's epithelial root sheath
47
What determine the outline of the root, dentin & number of roots the tooth will have?
Hertwig's epithelial root sheath
48
Hertwig's epithelial root sheath is removed before the _____ is laid down
Cementum
49
Enamel formation stops at the termination of the:
Enamel organ
50
Enamel formation stops at the termination of the enamel organ, but _____ continues & pushes the tooth ______
Dentin formation
Occlusally
51
The epithelial diaphragm is the modification of the Hertwig's sheath creating septa that divide into ____ & create _______
Pulpal tissue
Multiple roots
52
Root length is not complete until _______ after the tooth is emerged into the oral cavity
1 to 4 years
53
After the tooth is emerged into the oral cavity what happens with the roots?
Pulp chamber narrows
Apical opening constricts
54
What type of growth described tooth development?
Appositional growth
55
During the apposition stage of tooth development, the stratum intermedium produces:
Alkaline phosphatase
56
During the apposition stage the inner enamel epithelium forms _____ which will ultimately form ____
Ameloblasts
Enamel
57
During the aposition stage of tooth development the peripheral cells of the dental papillae forms _____ which will ultimately form _____
Odontoblasts
Dentin
58
What is the first formed dentin called?
Mantle dentin
59
Mantle dentin contains what types of collagen?
Type I & III
60
In the mantle dentin, the collagen fiber in the matrix are oriented ____ to the DEJ
Perpendicular
61
The presence of the mantle dentin stimulates the:
Ameloblasts to secrete enamel matrix
62
During the aposition stage of tooth development the ameloblasts migrate ____ while the odontoblasts migrate ____
Ameloblasts- peripherally
Odontoblasts- inward (centrally)
63
Describe actively secreting ameloblasts:
Describe inactive ameloblasts:
Tall, columnar cells
Short columnar or elongated cuboidal cells
64
At the final stage of mineralization the reduced ameloblasts with the remaining cells of the outer enamel epithelium, stellate reticulum & stratum intermedium form a membrane on the surface of the enamel. This is termed:
Primary cuticle
65
The primary cuticle may also be called:
Nasmyth's membrane
66
What are the four abnormal development categories:
1. Anodontia
2. Hypodontia
3. Oligodontia
4. Hyperdontia
67
Refers to the total lack of tooth development:
Anodontia
68
Refers to the lack of development of one or more teeth
Hypodontia
69
Refers to the lack of formation of six or more teeth (a subdivision of hypodontia)
Oligodontia
70
Refers to the development of an increased number of teeth (the additional teeth are termed supernumerary)
Hyperdontia
71
Defect that originates during initiation stage that results in the development of one ore more extra teeth:
Supernumerary teeth
72
What stage do supernumerary teeth arise in:
Initiation stage
73
The most common manifestation of supernumerary tooth formation:
Mesodens
74
Results in multiple small fragments of tooth structure, consisting of dentin, enamel, cementum or any combination, this occurs during the initiation stage
Odontoma
75
What stage does odontoma occur in?
Initiation stage
76
Comprised of a conglomerate mass of enamel & dentin that bears no anatomic resemblance to a tooth:
Complex odontoma
77
Comprised of multiple tooth-like structures:
Compound odontoma
78
An enlargement of the body & pulp chamber of multirooted teeth with apical displacement of the bifurcation (for example an exceptionally long root trunk with very short roots):
Taurodontism
79
Defined as an abnormal angulation or bend in the root:
Dilaceration
80
Defect that originates during Cap stage of development that results in large single-rooted tooth with one pulp cavity & exhibits "twinning" in crown area:
Gemination
81
During what stage of tooth development does gemination take place in?
Cap stage
82
Tooth count is normal when the double tooth is counted as one in this form of abnormal tooth development:
Gemination
83
Refers to a double tooth in which the tooth count reveals a missing tooth when the double tooth is counted as one:
Fusion
84
Defect occurring during apposition & maturation stages that results in union of root structure of two or more teeth by cementum:
Concresence
85
Defect occurring during cap stage of development that results in an extra cusp due to defects on the enamel organ:
Tubercle formation
86
During what stage of tooth development does the concresence occur in?
Apposition & maturation stages
87
At what stage of tooth development does tubercle formation occur in?
Cap stage
88
Originates by separation of the dental follicle (dental sac) from the crown of an unerupted tooth:
Dentigerous cyst (AKA follicular cyst)
89
A dentigerous cyst is attached at the:
CEJ
90
Comprises 20% of all jaw cysts:
20%
91
Arise from the cells rests of the dental lamina (also called rests of serres)
Keratocystic odontogenic tumor
92
The OKC constitutes _____ of all odontogenic cysts
3-11%
93
60% of all cases of all odontogenic keratocyst cases are diagnosed in patients between the ages of:
10 & 40 years
94
OKCs are considered ______ cysts
Bone expanding
95
OCKs located in the posterior mandible often present as:
Multilocular lesions
96
What is the treatment choice for an OKC?
Surgical removal
97
What occurs 30% of the time following surgical removal of OKCs
Recurrence
98
Cyst wall of a keratocystic odontogenic tumor consists of a 6-8 cell layer of stratified squamous epithelium with _____ at the luminal surface
Parakeratosis
99
The lumen of an odontogenic keratocyst (OKC) is often filled with:
Keratin
100
In an OKC, the presence of inflammation will generally cause epithelial ____ & _____ of the basal cell layer
Proliferation
Pallisading
101
The most common neoplastic lesion arising from odontogenic epithelium:
Ameloblastoma
102
What type of epithelium does an ameloblastoma arise from?
Odontogenic
103
Considered a slow growing, locally invasive tumor that has a multiolocular or "soap bubble" appearance on radiographs:
Ameloblastoma
104
Ameloblastomas are ______ when it comes to radiation
Radio-resistant
