Midterm Exam Flashcards
1
Q
separates dentin from enamel
A
dentinoenamel junction
2
Q
What exits the apical foramen?
A
nerves
3
Q
where anatomic crown meets anatomical root
A
cementoenamel junction
4
Q
where cementum and dentin meet
A
cementodentinal junction
5
Q
no blood supply, no nerves
A
avascular
6
Q
What is the final job of ameloblasts?
A
to form nasmyth’s membrane
7
Q
What does nasmyth’s membrane do?
A
protects enamel
8
Q
imperfect enamel formation
- little holes in teeth, discolored
A
amelogenesis imperfecta
9
Q
What is the result of too much fluoride ingested?
- modeled, white coloration
A
fluorosis
10
Q
What happens in children that get lots of fevers and/or infections?
A
enamel damage
11
Q
hard tissue loss from tooth-to-tooth movement
- grinding, bruxism
A
attrition
12
Q
chemical means tooth decay
- acid reflex, bulimia, soda
A
erosion
13
Q
wearing away tooth surface by mechanical means
- brushing teeth too hard
A
abrasions
14
Q
combination of abrasion of CEJ and grinding
A
Abfraction
15
Q
what do dentin and pulp develop from
A
dental papilla
16
Q
What is softer than enamel but still as hard as bone?
A
Dentin
17
Q
genetic condition with imperfect genetic formation, dentin can’t support house
A
dentinogenisis imperfecta
18
Q
Babies teeth are affected because of mother taking tetracycline, grey colored
A
tetracycline staining
19
Q
secreted layers of enamel, dentin, and cementum matrix
A
apposition
20
Q
mineralization completes
A
maturation
21
Q
inner enamel epithelial cells elongate and differentiate into pre-ameloblasts
A
Bell stage
22
Q
What begin to lay down hydroxyapatite crystals and mineralization begins?
A
dentin and enamel
23
Q
process of enamel matrix formation known as the apposition stage of tooth development
A
amelogenesis
24
Q
what is the hardest tissue of the body
A
enamel
25
what can only be removed by rotary cutting instruments
enamel
26
what is 96% mineralized
enamel
27
what forms from ameloblasts and is avascular
enamel
28
what develops from the enamel organ
enamel matrix
29
outer layer of epithelial cells
ectoderm
30
what form from the inner enamel epithelium
ameloblasts
31
how many ameloblasts join together to form the enamel rod
3 to 4
32
a column of enamel that runs perpendicular to the CEJ and extends to the surface of the tooth
enamel rods
33
what is the stage when ameloblasts excrete the enamel matrix
mineralization stage
34
during what stage do crystals grow and begin to calcify
maturation stage
35
incremental growth lines seen in sections of enamel described as brown in color
lines of retzuis
36
horizontal lines seen on the labial surface of anterior teeth
imbrication lines
37
When does root development occur
after crown of tooth is formed
38
what is root development formed from
cervical loop
39
what is responsible for the shape of the roots
hertwigs epithelial root sheath
40
what has genetic control and determines the shape of tooth
the dental papilla
41
what is 70% mineralized
dentin
42
what is softer than enamel
dentin
43
what is formed from odontoblasts
dentin
44
what is yellow- white in color
dentin
45
what makes up the bulk of the tooth and is present on both the crown and root
dentin
46
what secrete the matrix at the dentoenamel junction and the cells move toward the pulp
odontoblasts
47
dentin that is formed before the apical foramen is complete in the root
primary or regular dentin
48
formed after the completion of the apical foramen and continues to form throughout the life of the apical tooth
secondary dentin
49
formed as a result of localized injury to exposed dentin; can form quickly
tertiary (reparative, reactive) dentin
50
dentinal tubules are fully calcified associated with chronic injury
sclerotic dentin
51
incremental lines (growth rings) in dentin similar to the lines of retzius in enamel
imbrication lines of von Ebner
52
what develops from the mesoderm tissue of the dental papilla
the pulp
53
where is the pulp chamber
in the crown
54
where is the pulp canal
in the root
55
what is blood vessels, lymphatic vessels, nerves, fibroblasts and collagen fibers and cells of connective tissue
the pulp
56
what is soft - not calcified or mineralized
pulp
57
last portion of tooth to form after the crown erupts
apical foramen
58
small calcified circular areas found in the pulp chambers of older persons
pulp stones
59
what function of dental pulp is dentin producing cells (odontoblasts)
formative
60
what function of dental pulp is the nerve ending relay sense of pain so we feel it
sensory
61
what function of dental pulp can pass from heart to tooth in 6 seconds
nutritive
62
what function of dental pulp lays reparative dentin
defensive or protective
63
what is the dull yellow external layer of tooth root
cementum
64
what is very thin especially at the cervical line
cementum
65
what is 50-65% mineralized
cementum
66
what is hard as bone but softer than enamel
cementum
67
what develops from dental sac
cementum
68
what is produced by cementoblasts
cementum
69
What is odontogenesis?
tooth development
70
when does odontogenesis begin
6 weeks in utero
71
what is the longest growth period of all organs
odontogenesis
72
What are the stages of tooth development in order?
Initiation stage
Bud stage
Cap stage
Bell stage
Apposition stage
Maturation stage
73
When is the initiation stage?
6-7 weeks
74
What week is the bud stage?
8th week
75
When is the cap stage?
9-10 weeks
76
What are the three MAIN stages of tooth development?
Bud, Cap, and Bell stages
77
What is the primitive mouth (stomodeum) lined by?
ectoderm
78
What gives rise to the oral epithelium?
ectoderm
79
Consists of two horseshoe-shaped bands of tissue which will become the two arches/jaw
oral epithelium
80
What migrates to area to influence ectomesenchyme tissue?
neural crest cells
81
What are the oral epithelium and ectomesenchyme separated by?
basement membrane
82
What grows at end of the 7th week?
oral epithelium
83
Oral epithelium grows deeper into ectomesenchyme to produce what?
dental lamina
84
What starts at the midline and spreads posteriorly to the molar area?
Dental lamina
85
Absence of single or multiple teeth
anodontia
86
extra tooth or teeth
supernumerary teeth
87
What stage is extensive growth of the dental lamina into tooth germ penetrating into ectomesenchyme?
Bud stage
88
How many buds will be present for primary and permanent dentitions?
Primary - 20 buds
Permanent - 32 buds
89
In areas where teeth don't develop the dental lamina remains thickened and becomes what?
oral mucosa
90
What stage is when proliferation of growth of cells continues?
Cap stage
91
What leads to the formation of a cap shape attached to the dental lamina?
Cap stage
92
predominant process during cap stage is what?
morphogenesis
93
A depression results in the deepest part of each tooth bud of dental lamina and forms a cap or what?
enamel organ
94
During cap stage, inner mass of ectomesenchyme now becomes what?
dental papilla
95
During cap stage, remaining ectomesenchyme surrounding the outside becomes what?
the dental sac
96
At the end of the cap stage, what three embryological structures are now considered to be tooth germs?
1. the enamel organ
2. dental papilla
3. dental sac
97
What will give rise to the four tissues that make up a tooth?
tooth germ
98
What are the four tissues that make up a tooth?
- enamel
- dentin
- cementum
- pulp
99
"tooth without tooth"
dental papilla
100
Formation of tooth bud in cap shape with deep central depression
enamel organ
101
what is the future dental tissue produced from the enamel organ?
enamel
102
Condensed mass of ectomesenchyme within the concavity of the enamel organ
dental papilla
103
what is the future dental tissue produced from dental papilla?
dentin and pulp
104
condensed mass of ectomesenchyme surrounding the enamel organ
dental sac
105
what future dental tissue is produced from the dental sac?
"PAC" the sac
PDL
Alveolar bone
Cementum
106
tooth germ tries to divide
- tooth count is normal
germination
107
union of two adjacent tooth germs
- one less tooth count
fusion
108
extra cusp
tubercle
109
What stage is the continuation of proliferation, differentiation, and morphogenesis?
Bell stage
110
What are the four developing tissues of the enamel organ?
- outer enamel epithelium
- stellate reticulum
- stratum intermedium
- inner enamel epithelium
111
Where are cubodial cells?
outer enamel epithelium
112
What is a protective barrier for enamel organ during enamel production?
outer enamel epithelium
113
more outer star-shaped cells in many layers forming a network
stellate reticulum
114
What supports production of enamel matrix?
- stellate reticulum
- stratum intermedium
115
compressed layer of flat to cubodial cells
stratum intermedium
116
what is the innermost layer?
inner enamel epithelium
117
What are tall columnar cells?
inner enamel epithelium
118
What will differentiate into enamel secreting cells (ameloblasts)?
Inner enamel epithelium
119
What are secreting cells?
ameloblasts
120
What are the two developing tissues of the dental papilla?
- outer and inner cells of the dental papilla
121
What are nearest to inner enamel epithelium?
outer cells of dental papilla
122
Where does the basement membrane exist between?
between the inner enamel epithelium and the outer cells
123
What will differentiate into odontoblasts that form dentin matrix?
Outer cells of dental papilla
124
- inner cell mass
- will differentiate into pulp tissue
inner cells of dental papilla
125
What stage is when enamel, dentin, and cementum secrete in successive layers initially as a matrix
Apposition stage
126
What stage is when dental tissues fully mineralize?
maturation
127
What is the order of odontogenesis?
1. ectoderm
2. dental lamina
3. enamel organ
4. inner enamel epithelium
5. ameloblasts
6. enamel
128
What numbers are the maxillary incisors?
#7-10
129
What numbers are the mandibular incisors?
#23-26
130
What years do the maxillary central incisors (#8-9) usually erupt?
years 7-8
131
What years do the maxillary lateral incisors (#7 and #10) usually erupt?
years 8-9
132
What years do the mandibular central incisors (#24-25) usually erupt?
years 6-7
133
What years do the mandibular lateral incisors (#23 and #26) usually erupt?
Years 7-8
134
What are the functions of the incisors?
Cut food
Articulate speech
Support lips
Guide mandible during movement
135
How many lobes do incisors develop from?
4 lobes
136
What are mamelons?
Round bumps on incisal edges
137
What is diastema?
space between teeth, typically between central incisors
138
What are diastema's a result from?
frenum attachment
139
What years do all incisors typically erupt by?
6-9 years
140
What are developmental lobes?
little pockets for growth centers
141
Small maxillary incisors
Peg-lateral
142
What teeth are symmetrical?
Mandibular central incisors
143
What is it called when you twist a tooth?
Distolingual twist
144
Where are the facial and lingual heights of contour for canines located?
Cervical third
145
Where is the contact of the maxillary lateral incisors located?
Middle-third
146
What is the largest CEJ curvature of all teeth?
Mesial of the maxillary central incisors
147
Where are the mesial and distal marginal ridges of incisors located?
The mesial and distal borders of the lingual surface
148
What teeth have wider and longer crowns?
Maxillary central incisors (#8-9)
149
What teeth numbers have the smallest root-to-crown ratio?
#8 and #9
150
What teeth have smaller crowns - narrowest tooth mesiodistally?
Mandibular central incisors (#24-25)
151
What teeth have one pulp horn?
Maxillary lateral incisors
152
What's another name for the facial surfaces of anterior teeth?
Labial
153
What's another name for the lingual surface of maxillary teeth?
Palatal surface
154
Surface closer to midline
Mesial
155
Surface away from from midline
Distal
156
Imaginary junction line where two surfaces meet
Line angle
157
Elevation or peak on the occlusal surfaces of posterior teeth and the incisal edge of canines
Cusp
158
Greatest bulge on facial and lingual crown surfaces
Height of contour
(Crest of curvature)
159
Continuous space around each contact area
Embrasure spaces
160
What are the last teeth to be lost from dental disease?
Canines
161
What are the longest teeth in a permanent dentition?
Canines
162
What are the numbers of the maxillary canines?
#6 and #11
163
What are the numbers of the mandibular canines?
#22 and #27
164
What years do maxillary canines erupt between?
years 11-12
165
What years are maxillary canines root completion?
Years 13-15
166
What years do mandibular canines erupt between?
Years 9-10
167
What year are mandibular canines root completion?
Year 13
168
What are the functions of the canines?
Support lips
Cut, pierce, and shear food
Protection mechanism
169
What are the lobes of the canines?
3 facial lobes
1 lingual lobe
170
How many cusps on the incisal edge of canines?
One cusp
171
What teeth have the largest cingulum of all anterior teeth and is centered over the midroot axis?
Maxillary canines
172
What angle do mandibular lateral incisors have?
Rounded distal angle
173
What heights of contour for the canines are located in the cervical third?
Facial and lingual
174
Where are the maxillary canines mesial contacts located?
The incisal/middle junction
175
Where are the maxillary canines distal contacts located?
Toward the middle third
176
Where are the mandibular canines mesial and distal contacts located?
The incisal third
177
What are the facial surface ridges of the canines?
Mesial cusp ridge
Labial ridge
Distal cusp ridge
178
What are the lingual surface ridges of canines?
Mesial marginal ridge
Lingual ridge
Distal marginal ridge
179
What ridges are shorter than distal cusp ridges on canines?
Mesial cusp ridges
180
What are mesial and distal cusp ridges also known as?
Cusp slopes or cusp arms
181
What are the specific longest teeth?
Maxillary canines #6 and #11
182
What surfaces of canines appear to be smooth?
Lingual surfaces
183
What tooth roots bend distally at apex?
Maxillary canines
184
What teeth have more prominent distal root depression?
Mandibular canines
185
How many pulp horns do canines have?
One pulp horn
186
When do the maxillary first premolars erupt?
10-11 years
187
When do the maxillary second premolars erupt?
10-12 years
188
When do the mandibular first premolars erupt?
10-12 years
189
When do the mandibular second premolars erupt?
11-12 years
190
What are the functions of the premolars?
- Masticate food
- Maintain vertical dimension of the face
- Assist canines in cutting food
- Support corners of the mouth to keep from sagging
191
What are the developmental lobes for canines?
3 facial lobes
1 lingual lobe
192
What teeth often times form from two lingual lobes, resulting in two lingual cusps?
Mandibular second premolars
193
What do the lingual cusps form from on anterior teeth?
Cingulum
194
What is the facial height of contour for all premolars?
Cervical third
195
Where is the lingual height of contour for all premolars?
Middle third
196
Where are mesial contacts for all premolars located?
occlusal middle junction
197
Where are the distal contacts of premolars located?
NOT mand. first premolars
Middle third
198
Where are the distal contacts for the mandibular first premolars located?
Occlusal third
199
Where are crowns wider at for premolars?
Faciolingually
200
What cusp ridges do premolars have?
Mesial and distal cusp ridges
201
What merge together to make the occlusal table for premolars?
Cusp ridges of the buccal and lingual cusps
202
What form transverse ridges for premolars?
Two triangular ridges
203
Central grooves run ______ across the occlusal surface EXCEPT mandibular 1st premolars.
Mesiodistally
204
Fossas contain pits in the center making them suseptible to what?
Decay
205
What teeth have longer mesial cusp ridges and more prominent buccal ridges?
Maxillary 1st premolars (#5 and #12)
206
What teeth are most often extracted for orthodontic purposes?
Premolars
207
Where does the central developmental groove run on premolars?
From mesial to distal pit
208
What premolars are smaller?
Maxillary 2nd premolars
(#4 and #13)
209
What premolars buccal cusp tip is more obtuse?
(120 degree angle)
Maxillary 2nd premolars
210
What teeth have a more symmetrical occlusal outline?
Maxillary 2nd premolars
211
What teeth do the crowns tilt lingually?
Mandibular premolars
212
What teeth's lingual cusp is relatively shorter than buccal?
Mandibular 1st premolars
213
What teeth's mesial marginal ridge is more horizontal?
Mandibular 2nd premolars
214
What premolars have a bifurcated root?
Maxillary 1st premolars
215
What teeth bend distally in the apical third?
Premolars
216
What teeth have two canals even if it has a single root?
Maxillary 1st premolars
217
How many pulp horns do premolars have?
Most have 2
Mand. 2nd may have 3
