Maxillary and Mandibular incisors (complete) Flashcards
What is the main function of the incisors
To cut and tear food during mastication
What are the secondary functions of the incisors
- articulate speech
- support lips (esthetics)
- guide mandible during movement
What do all teeth develop from
lobes
What is the minimum number of lobes a tooth can have
4
how many lobes do anterior teeth develop from
4
where are the lobes on anterior teeth located
3 on the facial side and incisal edge, one on the lingual surface
Where are the lobes found in molars
on the cusps
where are the lobes found in premolars
on the two cups and two marginal ridges
What is the shape that ALL crowns from the facial and lingual aspects. and how is it oreinted
Trapezoids, with the shorter of the parallel sides being gingival
What is the shape of the maxillary posterior teeth from the proximal aspect, and how are they oriented
trapezoids, with the longer of the parallel sides being gingival
What is the shape of the mandibular posterior teeth from the proximal aspect, and how is that shape oriented
Rhomboids, with the occlusal end of the teeth slanting towards the lingual side of the tooth
What is the shape of the anterior teeth from the proximal aspect, and how is that shape oriented
triangles, with the base of the triangle being gingival
What is the initiation of calcification for the mandibular Central incisor
3.5 months
What is the initiation of calcification for the mandibular lateral incisor
3.5 months
When is the crown of the mandibular central incisor completed
4.5 years
when is the crown of the mandibular lateral incisor completed
4.5 years
when does the mandibular central incisor erupt
6.5 years
when does the mandibular lateral incisor erupt
7.5 years
when is the root of the mandibular central incisor complete
9 years
when is the root of the mandibular lateral incisor complete
10 years
What are the identifications of the mandibular central incisors according to all three systems
24, 25 - universal
(lower left bracket) 1, and (lower right bracket) 1 - palmer
41, 31 - international
on the mandibular central incisor, how does the incisocervical crown dimension compare to the mesiodistal crown dimension
the incisocervical crown dimension is greater than the mesiodistal crown dimension
What is the smallest tooth in the mouth
the mandibular central incisor
Which tooth in the mouth is the most symmetrical (mesial/distally)
The central mandibular incisor
What are the proximoincisal angles like on the mandibular central incisor
they are the sharpest, and neither of them are really rounded
what is the incisal edge of the central mandibular incisor like
- it is straight
2. it is almost at a right angle to the long axis of the root
What are mamelons
they are manifestations of developmental depressions (small bumps on the edges, and middle of the incisal edge)
Why don’t we see many mamelons in adults
because they are worn away by function
What are the facial developmental grooves and depressions like on the central mandibular incisors
they are the fewest and smallest in the mouth along with the lateral mandibular incisors
Where are the proximal contacts of the central mandibular incisors located
in the incisal 1/3 at the same level as each other
Where in the cingulum on the mandibular central incisors
- on the lingual side of the tooth
- in the cervical 1/3 of the crown
- slightly offset to the distal from the axis of the root
What is the lingual surface anatomy of the mandibular central incisors like
the smoothest in the mouth (along with mandibular lateral incisors) the grooves, pits and ridges are very small if they are there at all
Can you distinguish between the mandibular and maxillary incisors by the lingual surface anatomy?
yes
How does the incisocervical crown dimension compare to the faciolingual crown dimension of the mandibular central incisors
the incisocervical crown dimension is greater than the faciolingual crown dimension
Where is the incisal edge of the mandibular central incisor located when looking at it from a proximal view
it is located lingual to the center of the root
Why is the incisal edge of the mandibular central incisor located linguallly
because the mandibular arch sits inside the maxillary arch.
What happens to the incisal edge of the mandibular central incisor due to wear (seen from the proximal view(
The incisal edge inclines facially
Where is the facial height of contour on the mandibular central incisor
in the cervical 1/3
Where is the lingual height of contour on the mandibular central incisor
in the cervical 1/3 (slighly inferior to the facial height of contour)
What is the shape of the lingual surface from a proximal view of the mandibular central incisor
S- shaped
What is the shape of the facial surface from a proximal view of the mandibular central incisor
Flat
What is the height of contour
the place where the tooth would first touch if we drew a line parallel to the axis of the root
What is the cervical line for like mesially and distally of the mandibular central incisor
on the mesial side it curves incisally 2-3 mm on average
on the distal side it curves incially, but less than it does on the mesial side
What is the root surface form like on the mandibular central incisor
- the developmental groove depression is usually more pronounced on the distal side
- roots are wider faciolingually than mesiodistally
How does the faciolingual crown dimension compare to the mesiodistal crown dimension on the mandibular central incisor
the faciolingual crown dimension is greater than the mesiodistal crown dimension
How does the incisal edge look on the mandibular central incisor from the incisal view
it is straight mesiodistally (perpendicular to the faciolingual bisector)
What is the most notable characteristic of the mandibular central incisor from the incisal view
the symmetry of the mesial and distal halves of the crown
What are the identifications of the mandibular lateral incisors according to all three systems
26,23 - Universal system
(bottom left bracket) 2, (bottom right bracket) 2 - palmer
42, 32 - international system
How common is it to have a labial and lingual root division on the mandibular lateral incisor
rare
is it more or less common to have two canals in one root on the mandibular lateral incisors than it is to have labial and lingual root division
more common
on the mandibular lateral incisor, how does the incisocervical crown dimension compare to the mesiodistal crown dimension
the incisocervical crown dimension is greater than the mesiodistal crown dimension
Which is wider mesiodistally, the mandibular central incisor, or the mandibular lateral incisor
the mandibular lateral incisor
Does the incisal edge of the mandibular lateral incisor slope cervically from the facial view?
yes, it slopes cervically toward the distal
From the facial view, is the mandibular lateral incisor symmetrical mesiodistally?
no, the mesial half is not symmetrical to the distal half. (the mandibular central incisor is)
What are the incisal angles like from the facial view on the mandibular lateral incisor
the mesioincisal angle is sharp
the distoincisal angle is more rounded
Where are the proximal contacts of the mandibular lateral incisor
in the incisal 1/3, close to the incisal edge
Where is the cingulum of the mandibular lateral incisor
on the lingual surface, offset to the distal
How do the marginal ridges of the mandibular lateral incisor compare?
The mesial marginal ridge is slightly longer incisocervically than the distal marginal ridge
What is the lingual fossa like on the mandibular lateral incisor
smooth and barely visible