Dentin Flashcards
(97 cards)
0
Q
Characterized as positively birefringent?
A
Dentin
1
Q
Color of dentin?
A
Yellow intrinsic color
2
Q
Organic material of dentin? (3)
A
- Collagen
- Ground substance
- Water
3
Q
Types of dentin. (4)
A
- Primary
- Secondary
- Tertiary
- Predentin/dentinoid
4
Q
Also known as orthodentin or regular dentin?
A
Primary dentin
5
Q
Other terms of tertiary dentin?
A
- Reactive
- Reparative
- Irregular secondary dentin
6
Q
Primary dentin is developed before or after tooth eruption?
A
Before tooth eruption
7
Q
It has regularly arranged dentinal tubules?
A
Primary dentin
8
Q
Peripheral layer of dentin found adjacent to the enamel in the crown and cementum in the roots?
A
Mantle dentin
9
Q
Layer of dentin containing collagen alpha fibrils?
A
Mantle dentin
10
Q
True or false. Incremental lines can be found in mantle dentin?
A
False
11
Q
Makes up the bulk of dentin?
A
Circumpulpal dentin
12
Q
Dentin consisting of beta fibrils and mucopolysaccharide grounds substance?
A
Circumpulpal dentin
13
Q
Acts as a lubricant or as shock absorber?
A
Mucopolysaccharide
30
Q
True or false. Dentin is hydrophilic?
A
True
31
Q
Intertubular dentin consist of what type of collagen fibers?
A
Type 1
32
Q
Dentinal tubules exhibit ___? shaped curvature.
A
S shaped
33
Q
Regularly arranged canals from pulp to DEJ/DCJ
A
Dentinal tubules
34
Q
True or false. Dentinal tubules are more pronounced in the incisal and cuspal areas.
A
False
35
Q
Why are dentinal tubules few in incisal/cuspal areas?
A
Due to crowding of odontoblasts as more dentin is formed
36
Q
True or false. Tubules in root dentin has less S curvature?
A
True
37
Q
Types of branching. (2)
A
- Dichotomous
- Greater branching
38
Q
Contents of dentinal tubules. (3)
A
- Odontoblastic process
- Periodontal space
- Intratubular nerve
39
Q
Other term for odontoblastic process?
A
Tome’s fiber or dentinal fiber
40
Cytoplasmic extension of odontoblasts?
Odontoblastic process
41
Found between the odontoblatic process and wall of the tubule?
Periodontoblastic space
42
Periodontoblastic space contains \_\_\_\_?
Dentinal fluid
43
Dentinal tubules filled with air?
Dead tracts
44
Causes of dead tracts? (2)
* Retraction of odontoblastic process
* Death of odontoblast
45
Occurs when dentinal tubules have become occluded with calcified material?
Sclerotic dentin
46
Glossy appearance of dentin is due to formation of?
Sclerotic dentin
47
Note: In sclerotic dentin, there is no odontoblastic process..
Filled with intratubular dentin instead
48
True or false. Sclerotic dentin decrease with age.
False. *Increases*
49
Part of tooth where sclerotic dentin is found?
* Apical 1/3 of root
* Midways between DEJ and pulp
50
Globular zones of dentin mineralization?
Calcospherites
51
Areas of hypomineralized dentin where calcospherites failed to fuse?
Interglobular dentin
52
Formation of interglobular dentin is due to? (2)
* Vitamin D deficiency
* Exposure to high levels of fluoride
53
True or false. Tubules in interglobular dentin are uninterrupted.
True
54
True or false. Interglobular dentin is found in circumpulpal dentin.
True
55
Black structures located in the root dentin adjacent to cementum?
Granular layer of Tome's
56
True or false. Granular layers of tomes is seen decalcified section?
False. Seen only in *ground* section
57
Incremental lines of dentin?
Von Ebner
58
Dentin is mineralized in a __ hour cycle?
12
59
Changes in coloration of dentin?
Contour lines of Owen
60
It intercepts the DEJ and meet an accompanying Striae of Retzius?
Contour lines of Owen
61
Formative organ of dentin?
Dental papilla
62
Embryonic origin of dentin?
Ectomesenchyme
63
Formation of dentin begins at what stage of tooth development?
Late bell stage
64
First sign of dentin formation?
Appearance of Von Korff's fibers
65
Fibrils of odontoblasts?
Beta fibrils
66
Composition of predentin? (2)
* Collagen fibers
* Ground substance
67
Theories of dentin sensitivity? (3)
* Direct conduction
* Transduction
* Hydrodynamic theory
68
An unusual feature of dentin-pulp complex?
Dentin sensitivity
69
Overwhelming sensation percipeived by dentin-pulp complex?
Pain
70
Stimuli of dentin sensitivity comes from? (3)
* Airwater spray
* Contact with a bur or probe
* Dehydration
71
Part of tooth where dentin is more sensitive?
* Along the DEJ
* Near the pulp
72
Theory states that dentin is directly innervated?
Direct conduction
73
Downside of direct conduction theory?
Not all tubules have nerves
74
Theory states that odontoblasts acts as receptors?
Transduction theory
75
Theory that states: Fluid movement stimulates receptors in the pulp
Hydrodynamic theory
76
Two treatments for hypersensitivity.
* Interrupt neural response to pain
* Occlude open tubules
77
Disturbance of dentin mineralization causes?
Dentinogenesis imperfecta
78
Dentinogenesis imperfecta is characterized by? (3)
* Abnormally translucent enamel
* Bulbous crown with short root
* Obliteration of the pulp
79
Placement of calcium hydroxide liner for deep cavities?
Indirect pulp capping
80
True or false. Sclerotic dentin is observed after endodontic therapy.
False.
## Footnote
No pulp or odontoblasts, therefore no sclerotic dentin formed
81
Houses the pulpal tissue?
Pulp cavity
82
Occupies the coronal pulp?
Pulp chamber
83
Occupies the radicular pulp?
Root canal
84
Openings of the pulp is called?
Orifices
85
Lateral branching of the main root canal?
Accessory canal
86
Allows communication between pulp and periodontal ligament?
Accessory canal
87
Serves as an avenues for spread of disease from one tissue to another?
Accessory canal
88
Where blood vessels and nerves enter and exit the tooth?
Apical foramen
89
Describe the apical foramen of newly erupted teeth.
Open and should not be extracted
90
True or false. As tooth completes its development, apical foramen becomes more centrally located.
False. More *eccentric*
91
What makes apical foramen more occlusally located than the anatomical apex? (2)
* Deposition of cementum
* Resorption of dentin
92
Narrowest portion of pulp cavity?
Apical constriction
93
Functions of pulp. (5)
* Inductive
* Formative
* Sensory
* Nutritive
* Defensive
94
Morphotic response of pulp?
* Formation of tertiary dentin
* Formation of sclerotic dentin
95
Inflammatory response of pulp?
Pulpitis
96
Structural components of pulp (4)
* Odontoblastic zone
* Cell free zone
* Cell rich zone
* Pulp proper/pulp core
98
Develops after root formation is completed?
Secondary dentin
99
Asymmetric reduction in size and shape of the pulp chamber?
Pulp recession
100
True or false. Secondary dentin is deposited slower than primary dentin?
True
101
Change in direction which marks the separation of primary and secondary dentin?
Schreger's line
102
Formed in response to noxious stimuli?
Tertiary dentin
103
True or false. Tertiary dentin has more dentinal tubules?
False. Fewer dentinal tubules
104
True or false. Tertiary dentin is found only on areas needed.
True
105
Uncalcified dentin
Predentin
106
It lines the innermost portion of dentin
Predentin
107
Predentin is calcified within ___ hours?
24 hrs
108
Covers the walls of dentinal tubules?
Intratubular dentin
109
Another term for intratubular dentin?
Peritubular dentin
110
True or false. Peritubular dentin is more mineralized and dense than intertubular dentin.
True
111
True or false. Peritubular dentin is continuously formed.
True
112
Found between the dentinal tubules?
Intertubular dentin
113
It forms the main bulk of dentinal material?
Intertubular dentin
