Midterms Flashcards
(110 cards)
1
Q
The second hardest mineralized tissue
A
dentin
2
Q
most prominent in the tooth, lies between the
enamel & the pulp chamber near the
dentinoenamel junction (DEJ).
A
Primary dentin
3
Q
It outlines the pulp chamber and referred to as
A
circumpulpal dentin
4
Q
It is mineralized and in the structural inter-
relation between the collagenous and
noncollagenous matrix components.
A
Primary dentin
5
Q
the outer layer closest to enamel is known as
A
mantle dentin
6
Q
Formed after root formation is complete, normally
after the tooth has erupted and is functional.
A
secondary dentin
7
Q
It grows much more slowly than primary dentin but
maintains its incremental aspect of growth.
A
secondary dentin
8
Q
this is important in determining the
form of cavity preparation for certain dental
restorative procedures.
A
pulp recession
9
Q
produced in reaction to various stimuli, such
as attrition, caries, or a restorative dental
procedure.
A
tertiary dentin
10
Q
it is produced by those cells directly affected
by the stimulus not like primary and secondary
dentin where it forms along the entire pulp-
dentin border.
A
tertiary dentin
11
Q
the cells forming tertiary
dentin line its surface or become included in
the dentin.
A
osteodentin
12
Q
tertiary dentin is also referred to as
A
reactive ot reparative dentin
13
Q
dentin begins at what stage of tooth development
A
bell stage
14
Q
dentin formation spreads down the cusp slope
as far as the ____ of the enamel
organ, and the dentin thickens until all the
coronal dentin is formed.
A
cervical loop
15
Q
are specialized cells that produce dentin through the
secretion of its collagenous and noncollagenous organic matrix
components and by controlling the mineralization process.
A
odontoblasts
16
Q
odontoblasts and fibroblasts slowly move towards the center of the tooth
by growing a protrusion from themselves,
which stays in place, embedded within the matrix, while the rest of the
cell moves toward the center of the tooth, towards the pulp. What is this process called
A
odontogenic processes
17
Q
The odontogenic processes secrete _______ , which
forms crystals and mineralizes the predentin
A
calcium hydroxyapatite
18
Q
In dentinogenesis, the odontoblasts secrete a soft organic matrix made out of proteins,
which is called
A
predentin
19
Q
Fibroblasts assist by creating a mesh
of thick collagen fibers, called
_____ which become the
framework for dentinogenesis
A
Korff’s fibers
20
Q
are thick collageneous fibers in the
developing tooth that begin in the dental papilla, spiral between the cells of the
odontoblast layer, and form the matrix of the dentin.
A
Korff fibers, also von Korff
21
Q
As the odontoblasts continue to increase in
size, they produce smaller collagen type 1
fibrils, oriented parallel to the future DEJ. In
this way, what layer appears
A
mantle predentin
22
Q
The plasma membrane of odontoblasts
adjacent to the differentiating ameloblasts
extends stubby processes into the forming
A
extracellular matrix
23
Q
One of these processes may penetrate the
basal lamina and interpose itself between
the cells of the IEE to form the
A
enamel
spindle
24
Q
As the odontoblasts forms these processes,
it also buds off membrane bound vesicles
A
matrix vesicles
25
The odontoblasts develop a cell process called the __________ which is left
behind in the forming dentin matrix as the
odontoblasts moves toward the pulp.
odontoblast process or Tomes fiber
26
is formed after root formation is
completed by the same odontoblasts that form
primary dentin
Secondary Dentin
27
extend
through the entire thickness
of the dentin from the DEJ to
the mineralization front and
form a network for the
diffusion of nutrients
throughout the dentin.
dentinal tubules
28
has
been shown to be
hypermineralized compared
to the intertubular dentin
though precise composition is
still not known
peritubular dentin
29
composes the main body of dentin
intertubular dentin
30
It is located between dentinal tubules or, more
specifically, between the zones of peritubular dentin
intertubular dentin
31
Term used to describe areas of
unmineralized or hypomineralized
dentin where calcospherites (globular
zones of mineralization) have FAILED to
fuse into a homogeneous mass within
mature dentin.
interglobular dentin
32
It is most common in circumpulpal
dentin (just below the mantle dentin).
interglobular dentin
33
Dentinal tubules which have become occluded with
calcified material
Sclerotic dentin
34
When the dentin of the root is viewed in
Ground Sections under transmitted light,
an area called ______ can
be seen just below the surface of the
dentin where the root is covered by
cementum.
granular layer of Tomes
35
soft connective that supports the
dentin
pulp
36
four distinct zones of pulp
odontoblastic zone
cell-free zone
cell-rich zone
pulp core
37
principal cells of the pulp
odontoblast, fibroblasts, undifferentiated ectomesenchymal cells, immunocompetent cells
38
It forms the natural barrier between the mineralized
tissues. Its active phase, prominent organelles and
resting phase smaller cells with fewer organelles.
ODONTOBLAST
39
The most abundant cells in the pulp. It maintains and form
the pulp matrix.
FIBROBLASTS
40
Referred to as "reserve cells" ,capable of maturing into
macrophages.
UNDIFFERENTIATED ECTOMESENCHYMAL CELLS
41
Has macrophages, Dendritic cells, and lymphocytes
IMMUNOCOMPETENT CELLS
42
- suggests that the dentin is innervated directly.
- It is not exactly the nerves that are simulated.
- It is the odontoblast itself that serves and acts as a receptor.
Transduction Theory`
43
- suggests that the odontoblast acts as a receptor.
- The sensitivity is caused by the movement of the dentinal tubules contents.
- Movement of fluid will cause sensitivity.
Hydrodynamic Theory
44
- suggests that the receptors at the base of odontoblasts are stimulated directly or
indirectly by fluid movement through the tubules.
- Any stimulation of the nerve endings found in the dentinal tubules will be the one
to receive
Direct Conduction Theory
45
Also referred to as denticles
pulp stone
46
Frequently found in pulp tissue, more
common at the orifice of the pulp
chamber or within the root canal.
pulp stone
47
- Progressive narrowing of the pulp space
- Due to the continuous deposition of dentin
- When pulp is getting thicker, pulp cavity
becomes smaller
PULP RECESSION
48
decrease in size of the pulp due to structural
ATROPHY OF PULP
49
deep carious lesions
CHRONIC PATHOLOGICAL PROCESSES
50
deep carious lesions
CHRONIC PATHOLOGICAL PROCESSES
51
differentiating
ameloblasts acquire their phenotype, change polarity, develop an
extensive protein synthetic apparatus, and prepare to secrete the
organic matrix of enamel. What is this stage
presecretory stage
52
during this stage, ameloblasts elaborate
and organize the entire enamel thickness, resulting in the formation
of a highly ordered tissue.
secretory stage
53
ameloblasts
modulate and transport specific ions required for the concurrent
accretion of mineral. Ameloblasts now are considered to be cells that
carry out multiple activities throughout their life cycle and that
upregulate or downregulate some or all of them, according to the
developmental requirements. What stage is this
maturation stage
54
The function of ameloblasts during this stage is determination of
shape of the tooth.
Morphogenetic stage - presecretory stage
55
The inner enamel epithelium interacts with underlying connective
tissue and through differential growth helps to establish the
dentino-enamel junction and thereby determine the shape of the
tooth to be formed.
Morphogenetic stage - presecretory stage
56
During this stage, the inner enamel epithelial cells undergo
differentiation to ameloblasts as a prerequisite for enamel
formation.
differentiation stage - presecretory stage
57
This stage is also named as organizing stage because during this
stage, the ameloblasts exert organizing influence on dental papilla
cells which are adjacent to them and help in their differentiation to
odontoblasts.
differentiation stage - presecretory stage
58
In this stage, ameloblasts perform the function of secretion of
enamel matrix and partial mineralization.
secretory stage
59
During this stage, ameloblasts helps in the mineralization and
maturation of enamel.
maturation stage - post-secretory stage
60
In this stage, ameloblasts have
to introduce the inorganic material necessary for maturation and also
reabsorb proteins and water to provide space for the minerals.
maturation stage - post-secretory stage
61
In this stage, ameloblasts along with other layers of enamel organ has to
perform a protective function.
protectice stage - post-secretory stage
62
what covers the newly formed enamel and protects it in post-secretory stage
reduced enamel epithelium
63
In this stage the reduced enamel epithelium secretes collagenase
enzyme which destroy the connective tissue between oral mucosa
and erupting tooth.
desmolytic stage - post-secretory stage
64
During this stage the reduced
enamel epithelium proliferates and fuses with the oral epithelium to
form a solid plug of epithelial cells.
65
During this stage the reduced
enamel epithelium proliferates and fuses with the oral epithelium to
form a solid plug of epithelial cells.
desmolytic stage - post-secretory stage
66
During this stage the reduced
enamel epithelium proliferates and fuses with the oral epithelium to
form a solid plug of epithelial cells.
desmolytic stage - post-secretory stage
67
2 step process of enamel formation
- enamel matrix deposition
- enamel matrix mineralization
68
The secretory ameloblasts which are
structurally suited for synthesis and secretion
of enamel proteins, start secretory function
after a layer of dentin is deposited. The
enamel matrix deposition
69
small to normal tops (crowns) of the teeth, upper and
lower teeth that do not meet showing a poor bite, and teeth that vary in color
from off-white to yellow-brown. The enamel thickness varies from thin and
smooth to normal, with grooves, lines and/or pits.
Hypoplastic (Type 1)
70
exhibits a normal thickness of the enamel, but its density
is the same as that of dentin. Commonly associated with an open bite and creamy
white to yellow-brown roughly surfaced teeth that may be tender and sore. The
enamel is generally normal in thickness but tends to be chipped away or scraped.
Hypomaturation (Type 2)
71
imperfection in the formation of enamel
amelogenesis imperfecta
72
enamel thickness is normal, but its density is even less
(more radiolucent) than that of dentin. Patients with an open bite and creamy white
to yellow-brown rough enamel-surfaced teeth that may be tender and sore. These
teeth usually carry substantial precipitates of stony material from the fluids of the
mouth (calculi). The enamel is generally normal in thickness but tends to be chipped
away or scraped.
Hypocalcified (Type 3) -
73
smaller than normal
teeth, the color of which may range from white to yellow-brown, and teeth that
appear to be mottled or spotted. The enamel is thinner than normal with areas that
are clearly less dense (hypomineralized) and pitted.
Hypomaturated-hypoplastic with taurodontism (Type 4)
74
formative cell of dentin
odontoblast
75
formative organ of dentin
dental papilla
76
embryonic origin of dentin
ectomesenchyme
77
The ______ from what used to
be as dental papilla is due to the expression of
signaling molecules and growth factors in cells of
IEE.
Odontoblast differentiation
78
containing fine collagen
fibrils, separates undifferentiated cell of
dental papilla (preodontoblasts) from
differentiating IEE (ameloblasts)
acellular zone
79
formation of mantle dentin
deposition of matrix and mineralization
80
An avascular hard tissue that covers
the roots of teeth from CEJ to apex
cementum
81
2 development of cementum
prefunctional and functional stage
82
A development stage of cementum that occurs during root formation
Prefunctional Stage
83
A development stage of cementum that occurs throughout occlusion and life
functional stage
84
types of cementum
acellular and cellular
85
a type of cementum that is for attachment of teeth to PDL
acellular cementum
86
a type of cementum that is for the continuous repair and movement of periodontium
cellular cementum
87
functions of cementum
anchorage, coverage, compensation, eruption and resorption and repair
88
Formerly called as
“Coronal Cementum"
A mineralized matrix that contains
neither collagen fibers nor
cementocytes
acellular afibrillar cementum
89
Referred to as
“ Secondary Cementum”
Contains both extrinsic Sharpey’s
fibers & intrinsic bundles of collagen
fibers in the cementum
CELLULAR MIXED FIBER
CEMENTUM
90
Formerly called as
“Primary Cementum ” or “Fibrous Cementum”
- Consists of Sharpey’s Fibers
- Extrinsic collagen fibrils
ACELLULAR EXTRINSIC
FIBER CEMENTUM
91
- Contains both cementocytes &
intrinsic bundles of collagen fibrils
- Products that are specific to
cementoblasts
- Formed only during reparative
process
CELLULAR INTRINSIC
FIBER CEMENTUM
92
- A thin, non-cellular, amorphous layer of hard tissue (10 μm thick)
- The first layer deposited
- Deposited in the epithelial root sheath's
inner layer
- Seals the tubules of
dentin
- Composed of enamelin
instead of collagen
INTERMEDIATE
CEMENTUM
93
spaces within the matrix which houses the cell bodies of cementocytes
lacunae
94
elongated, tiny spaces housing the processes
Canaliculi
95
- Collagen fiber formed by fibroblasts of the PDL
- Referred to as extrinsic fibers.
- Partly incorporated into the cementum.
sharpey's fibers
96
The cementoblasts also lay down fine collagen fibers in the
cementum
Intrinsic Fibers
97
- growth lines of cementum
- parallel with the cementum surface
- cementum is laid down at intervals as evidenced by the
appearance of resting lines (light & dark banding pattern) in
the cementum
- These lines indicate alternating periods of deposition and lack
of deposition of cementum.
Incremental Lines of Salter
98
- Form the cementum
- Found lining the root surface
Interposed between bundles of PDL
- a cell found in cementum
Cementoblasts:
99
- Cementoblasts that are trapped in the lacunae during its
development
- Sparse amount of cytoplasm and numerous processes occupying
the canaliculi in the mineralized cementum matrix
Cementocytes
100
morphology of CEJ
30% percent of human teeth
10% have gaps between cementum and enamel
60% of the cementum overlaps the enamel
101
- Also known as excementosis
- characterized as the excessive
cementum formed usually
along the apical portion of
root
- can cause difficulty in
execution of certain dental
procedures (e.g. tooth
extractions, root canals etc.)
HYPERCEMENTOSIS
102
steps in cementum formation
matrix deposition and mineralization
103
- Extension of the cervical loop (OEE+IEE)
- This bilayered sheath has dental papilla
on one side and dental sac on the other
side.
Hertwig’s Epithelial Root Sheath (HERS)
104
- It sends signals to the dental papilla to
differentiate into odontoblasts
- The odontoblasts start depositing the
radical dentin.
- The root dentin deposition sends signals
for the differentiation of cementoblasts
Hertwig’s Epithelial Root Sheath (HERS)
105
this degeneration exposes the
ectomesenchymal cells of the
dental sac to the radical dentin = deposit cementum
cells of the dental follicle
106
the cells of HERS starts degenerating
CELLS OF THE DENTAL FOLLICLE
107
the HERS receives signals that form the epithelial
mesenchymal transformation
differentiate into cementoblasts
= deposit cementum
CELLS OF HERS
108
FORMATION OF CELLULAR INTRINSIC
FIBER CEMENTUM
CELLS OF THE DENTAL FOLLICLE
109
FORMATION OF
ACELLULAR
INTRINSIC FIBER
CEMENTUM
CELLS OF HERS
110
an outermost thin layer of non-mineralized cementum just adjacent to the cementoblast
cementoid
