Basic Terminology, Dentition, Numbering, Morphology of Crowns Flashcards
(93 cards)
1
Q
Dentition
A
Primary-6 mo-2 yr
Permanent- 6yr new teeth erupt, start losing
-at 21 permanent complete
2
Q
Arch
A
Maxillary or Mandibular
3
Q
Quadrant
A
half an arch
4
Q
Anterior teeth
A
canines and incisors
- behind lips
- first 3 from midline in each quadrant
5
Q
Midline
A
separates arches into quadrants
6
Q
Name the 4 classes of teeth
A
Incisors
Canines
Premolars
Molars
7
Q
Incisors
A
cut food
8
Q
Canines
A
Pierce food
9
Q
Premolars
A
piercing and minor grinding of food
10
Q
Molars
A
Solely for grinding food, large surface area for smashing food well
11
Q
3 Types of teeth
A
1) Central and lateral (just single canine in each quadrant, no types)
2) 1st and 2nd (premolars)
3) 1st, 2nd, and 3rd (molars)
12
Q
Primary teeth
A
Deciduous teeth
Only 20 teeth
-NO premolars
1st and second premolars, 3rd molars NOT present
A-T in UNS (NO numbers)
13
Q
Adult teeth are numbered _ - _ in the Universal Numbering System
A
1-32
Start maxillary right (9oclock) 1st tooth #1 is 3rd Molar
top right clockwise
14
Q
Name the 4 tissues of the tooth
A
Enamel
Dentin (shaded gray)
Cementum
Pulp
15
Q
Enamel
A
Strongest tissue in body
- ameloblasts
- white but lots translucency
16
Q
Dentin
A
shaded gray 70% Ca hydroxyapetite -odontoblasts -yellow in color -right inside enamel, can't be seen unless looking at rad
17
Q
Cementum
A
surrounds root of tooth, thin layer, cementoblasts
yellowish in color, has 50-65% Ca hydroxyapet.
same density of bone
18
Q
Pulp
A
inside, only soft tissue on tooth
made of connective tissue with
blood vessels and nerves,
makes tooth vital organ
19
Q
Cervical area of tooth
A
Neck
20
Q
Apical foramen
A
apex=tip of root
foramina=openings
21
Q
Root canal
A
innermost channel of pulp leading to pulp chamber
22
Q
Pulp chamber
A
below dentin, reaches slightly into anatomical crown
23
Q
Cementodentinal Junction
A
CDJ
24
Q
Cementoenamel Junction
A
CEJ
-where crown and root anatomically separate
25
Dentinoenamel junction
can't see cause inside tooth
26
pulp horns
projections, have to stay away
| so you dont expose pulp
27
enamel covers anatomical ____
| cementum covers anatomical ____
crown
root
28
anatomical crown never changes
but clinical _____ changes during life for
different reasons
clinical root and crown changes
29
Anatomical crown
covered with enamel
30
Anatomical root
covered with cementum
31
When do the terms clinical crown and root apply?
ONLY when tooth is in mouth and at least partially erupted
32
Periodontium
surrounding tissues of tooth
- gingiva (free vs attached)
- cementum
- periodontal ligament
- bone (alveolar bone)
33
labial or facial
anterior teeth surface toward lips
34
buccal or facial
posterior teeth
| surface toward cheeks
35
lingual or palatal
maxillary teeth surface toward tongue
36
lingual
mandibular teeth toward the tongue
37
incisal edge or ridge
anterior teeth biting surface
38
occlusal surface
posterior teeth biting surface
39
each tooth has __ proximal surfaces
2
mesial
distal
40
Mesial
proximal surfaces that face the midline of an arch
41
Distal
proximal surfaces that face away from the midline of an arch
42
divisions of crown from facial/lingual view
mesial, middle, distal
-occlusal/incisal (top), middle, cervical
43
divisions of crown from proximal views
facial, middle, lingual
occlusal/incisal, middle, cervical
44
List of surfaces for naming LAs, PAs
```
Mesial=1
Distal=2
Facial/Labial/Buccal=3
Lingual=4
Occlusal or Incisal=5
Cervical and Apical=6
```
45
surface junctions
two surfaces that join (line angle)
ex: distolabial, mesiobuccal
lose -al and +o
46
Dimension
the distance between two
opposite surfaces, such as:
Mesiodistal dimension
47
Root-to-Crown Ratio
Small ratio (smallest: 1.16-maxillary central incisor)
denotes nearly equal
crown and root length
Larger ratio (1.56-right maxillary canine)
denotes a relatively
larger root compared to
the crown
48
optimum root/crown ratio
2/3
49
minimum root/crown ratio
1/1
50
What is the longest crown?
mandibular canine or
| maxillary central incisor
51
Longest tooth
maxillary canine
52
Widest crown
mandibular first molar
53
Narrowest crown
mandibular central incisor
54
Cusps
rounded
-pyramid shaped with
four ridges
- Mesial cusp ridge
- Distal cusp ridge
- Facial cusp ridge
- Triangular ridge
55
Ridges
linear/linear bulges
56
Triangular ridge
from cusp tip to middle of tooth
present ONLY on POSTERIOR teeth
57
1-5 cusps
canines and posterior teeth
58
cusp ridges
cusp slopes or cusp arms
mesial and distal
59
Transverse (Oblique) Ridge
Two Triangular ridges joined together (triangular of DB and DL meet/line up from buccal to lingual)
60
Buccal (labial) cusp ridge
very subtle
61
Buccal Cervical Ridge
subtle
| -near CEJ mesially
62
Mamelons
Three bumps form on adult
Incisors from three labial lobes; Usually
wear away
63
Mamelons
Three bumps form on adult
Incisors from three labial lobes; Usually
wear away
64
Perikymata
Very small horizontal
wave-like ripples of Enamel on newly erupted
adult teeth
65
Depressions in teeth
fossae and grooves
66
Grooves
linear depressions
Major vs. Minor
67
Major Grooves
(developmental)
– Central groove
– Fossa grooves
68
Minor Grooves
(supplemental)
– Marginal ridge grooves
– Extra grooves
69
Central grooves
located in the
buccolingual center of
the tooth and run
mesiodistally
70
Fossa grooves
named for the surface
or line angle they “aim”
toward
71
Fossae
Shallow bowl-like depressions
Fossae on occlusal surfaces are located in
the intersection of the grooves
72
Pit and fissure
Decay starts in grooves and
spreads out more quickly once into Dentin
(softer than Enamel)
73
Pits
-often found within fossae (depressions)
```
Incisors (especially
maxillary) have one
broad, shallow fossa
(sometimes with a
lingual pit)
```
74
Two-cusped premolars have _ fossae
TWO
Mesial
Distal
75
Three-cusped premolars and most molars have ____
| fossae
THREE
– Mesial
– Central
– Distal
76
furcal area
area between roots if split
77
CEJ on proximal curves toward
occlusal/incisal
78
CEJ mesial curves ___ than distal
MORE than
79
CEJ on facial (or lingual)
| curves toward ____
root apex
80
CEJ curvature _______
from anterior to
posterior crowns
diminish
81
Root Axis Line
An imaginary line that splits the root in half (Mesiodistally or Faciolingually)
82
Height of Contour
Crest of Curvature)
83
Contact Areas
(or Proximal Heights of
| Contour): Protect Gingiva; Prevent Food Impaction
84
Embrasure Spaces
are ONLY present
when two adjacent teeth touch
```
• Four embrasures
– Facial
– Lingual (larger than
facial)
– Occlusal or incisal (often
quite small)
– Cervical = interproximal
space (filled with
gingiva)
```
85
Maxillary teeth from lateral view
Anteriors are mesially inclined
Posteriors are not
86
Mandibular teeth from lateral view
all mesially inclined
87
Tilt from frontal view
Maxillary teeth tilt facially
Mandibular teeth tilt lingually
88
Anteroposterior Curve (of Spee)
Maxillary curve is
convex
Mandibular curve is
concave
89
Mediolateral Curve (of Wilson)
-Maxillary curve is
convex
-Mandibular curve is
concave
90
Ideal Occlusion
Occlusion is the contact of the occlusal and incisal surfaces ofbmaxillary and mandibular teeth
91
Ideal Class I Occlusion Relationship (Angle's Classes)
```
Class I jaw relationship
is when the
mesiobuccal cusp of
maxillary first molar fits
into mesiobuccal
groove of mandibular
first molar (that is, the
most mesial of the two
buccal grooves)
```
Maximal intercuspal
position
Maxillary teeth are
FACIAL to mandibular
```
Buccal cusps of maxillary
teeth are facial to
mandibular
• Buccal cusps of mandibular
fit into maxillary fossae
• Lingual cusps of maxillary fit into mandibular fossa
• Lingual cusps of mandibular
are lingual to maxillary
```
92
Tooth Development From Lobes
Anterior teeth form
from four lobes (three
facial and one lingual)
Premolars form from
three facial lobes and
one lobe per lingual
cusp
Molars form from one
lobe per major cusps
93
functional/working cusp
cusp doing majority of the work
maxillary: lingual
mandibular: buccal
