Chapter 1 J: Dental Anatomy Flashcards
How many teeth are present in primary dentition?
20
How many teeth are present in permanent dentition?
32
Mixed dentition is between the ages of ?
6-12
Palatal refers to ?
Maxillary teeth
Lingual refers to?
Mandibular teeth
Proximal surfaces are?
Mesial and distal
A cusp is defined as?
An elevation on the crown portion
A tubercle is defined as?
A smaller elevation on the crown portion caused by extra formation of enamel
A cingulum is defined as?
The lingual lobe of an anterior tooth
What teeth are located on either side of the median line
Upper and lower central incisors
The most common agenesia is?
Upper lateral Incisors
The most common supernumerary?
Mesiodens
General shape of incisors (vestibular surface)?
Convex
General shape of incisors (lingual surface)?
Convex at the cingulum then turns to concave on the way to the incisal edge
Function of incisors?
- aesthetics (lip support)
- masticatory (incisal edge is used to cut food)
- phonetics (sound)
MAP
The tooth is divided into:
Crown, cervix, root, and apex of the root
Contacts of the incisors?
Lower incisors make contact to the lingual surfaces of the UCI and the mesial portion of the ULI
Which tooth is the dominant tooth of the upper arch and condiitons the whole facial aesthetics?
And the widest mesiodistally of any anterior tooth?
Upper central incisors
Shape and size of upper central incisors:
- widest mesiodistally of any anterior teeth
- trapezoid or rectangular shape
- Uniradicular
The only situation where the mesial surface of the same tooth contact? And where does this contact happen?
Central incisors
On incisal and middle third
8mm is the ?
Mesiodistal distance of UCI
10mm is the?
Cervico incisal distance of UCI
In regards to the UCI, which incisal angle is 90 degrees and which one is rounded?
Mesial and distal respectively
The vestibular aspect of the UCI is ?
Convex and the maximum convexity occurs at the cervical third.
Perikymata are
Horizontal lines on the vestibular surface of UCI
Why does the lingual surface of the UCI have less surface ?
MD convergence
Is the cingulum symmetrical in UCI?
No, it’s slightly distalized
Which marginal ridge is thicker and shorter in UCI?
Distal marginal ridge
Is the lingual fossa in the UCI convex or concave?
Concave
Which aspect is more convex in UCI (mesial or distal)?
Distal
The length of the root is ___ times the crown in the UCI?
1.25-1.5
Transversal cuts to the root in UCI results in?
A square near the cervix and a triangle near the apex
Roots are usually curved to ?
Distal
How many pulp chambers do the UCIs have and is there a delimitation between the chamber and the canal?
1, and no
ULI compared to CI:
Smaller, more symmetric, rounded incisal edge, smaller and deeper fossa, centred cingulum, thinner root.
Bigger: LCI or ULI?
ULI
Which tooth is the smallest and most symmetric?
LCI
The incisal edge of the LCI is:
Horizontal, right proximal angles
How many root canals do LCI have and is there a delimitation between the chamber and canal?
1 or 2 root canals (if 2: vestibular and lingual)
No delimitation
LLI compared to LCI?
- less symmetric
- bigger
- shorter root
Which tooth is the longest tooth and the hardest to extract?
Canines
Which tooth is located at the greatest angulation point of the dental arch?
Canines
Which tooth is the limit between the anterior and posterior sector?
Canines
Canines guide the __ movement?
Lateral
Class I canines:
Between the lower canines and the 1st premolars
Is the incisal edge of the upper canines symmetrical?
No, the distal cusp ridge is longer than the MCR
Is the cingulum centred in upper canine?
Yes, produces 2 fossae
Which lobe is developed and prominent in upper canines?
Middle lobe
Crown:root length of upper canines?
1:2
How many pulp chambers do upper canines have and is there a delimitation between the chamber and the canal?
1 and no
Lower canines in comparison to upper canines?
- cingulum is off centred and smoother ridges
- cusp tip towards mesial more than in upper canines
- shorter and straighter root
- 1 or 2 root canals
- can have 2 roots
What is the most common mandibular agenesia?
2nd premolar
What teeth substitute the primary molars and are not present in primary dentition?
Premolars
What cusp is prominent in premolars?
Vestibular
Do premolars have longer or shorter crowns and roots?
Shorter
Which teeth group maintain vertical dimension, prevent the cheeks from collapsing, and helps the canines in lateral movement (group function)?
Premolars
Which upper premolar is wider?
1st PM
Which tooth does this statement refer to? More rounded cusps, wider contact surfaces, and function more similar to molars (crushing)
Upper second premolar
How many cusps do upper premolars have?
1-3 cusps possible
How many pulp horns and canals do upper premolars have?
2 pulp horns corresponding to each cusp and 2 canals even if single root
Which cusp is 1mm higher in the upper first premolars?
Vestibular
How many roots do the upper second premolars have?
1
These root characteristics refer to which tooth?
- 1 root, flat MD
- 3/4mm shorter than canine
- 1 root canal
Lower first premolar
Which of the premolars could have two roots?
Upper first premolar
Lower second premolar: how many cusps?
Can have 3 and if 3, the distolingual cusp is the smallest
Molar general facts:
- important role in VD (facial aesthetics)
- maximum anchorage to bone: 2-3 roots
What tooth is the largest tooth in the upper arch?
First molar
How many cusps do upper first molars have?
- 4 + 1 undeveloped one (Carabelli’s cusp)
- 2 V + 2 P + carabelli
How many roots do the upper first molars have?
3
2 V + 1 P
Do the upper second molars have carabelli’s cusp?
No
How many cusps do the lower first molars have? and which ones are the active cusps?
5
2 V+ 2 L+ 1D
VIPS: VESTIBULAR INFERIOR, PALATAL SUPERIOR
Which cusp is higher in lower first molars?
Lingual cusps—>inactive are higher
How many roots and canals do lower first molars have?
- 2 roots (M&D) or can be fused into one, infrequently can be 3
- M root flat with 2 canals, MV&ML
- D root thinner with 1 or 2 canals
Which tooth is harder to extract and why?
Lower first molar or upper molars?
Lower first molars because of the properties of the mandible
How many cusps do the lower second molars have?
4
How many roots do third molars have?
Often fused into 1
What can be defined as… a small elevation on some portion of the crown roduced by an extra
formation of enamel?
A: cusp
B: tubercle
C: ridge
D: cingulum
B
A cusp can be described as an elevation or mound on the crown portion? T or F
True
What can be described as a lobe found on the lingual aspect of anterior teeth?
A: cingulum
B: cusp
C: ridge
D: fossae
A
The most common supernumerary is known as mesiodens? T or F
T
The second upper premolar is the most common missing tooth? T or F
?
What is the ideal ratio (length/width) on an upper central incisor?
A: 10/8
B: 10/9
C: 11/7
D: 11/8
A
What are Perikymatas?
A: vertical lines of development
B: horizontal lines of development
C: kymatic cells of enamel
D: kymatic cells of dentin
B
The root length on a central incisors is normally 1.25/1.5 times its crown? T or F
T
Canines have two marginal ridges and two cusp ridges? T or F
T
Which tooth is the smallest mesiodistally?
A: upper lateral incisor
B: upper central incisor
C: lower central incisor
D: lower lateral incisor
?
Which group of teeth are not present in primary dentition?
A: all are present
B: none are present
C: laterals
D: premolars
D
How many cusps does a lower first molar have?
A: 3
B: 4
C: 5
D: 6
5
How many roots does a lower first molar have?
A: 2
B: 3
C: 4
D: 5
A
What are the active cusps?
A: upper lingual
B: upper vestibular
C: upper lingual and lower buccal
D: upper vestibular and lower buccal
C
How many roots do upper first premolars have?
2
