Mandibular Premolars Flashcards
Buccal ridge prominence maxillary vs mandibular
max: more prominent
man: less prominent
distal crown tilt max vs man
max: No distal crown tilt relative to the root
man: Distal crown tilt relative to the root
difference between cusp heights max vs man:
max: Less difference between F and Li cusp heights (especially seconds)
man: More difference between cusp heights
(especially firsts)
maxillary pre-molars: central groove is ________ over the tooth
centered
man premolars: crown tilts to the _________ so buccal cusp tip almost _________ over the root
lingual
centered
Max premolar vs. Man premolar:
Crown considerably wider
faciolingually than
mesiodistally
Crown closer to square or
round
Maxillary
Mandibular
Man 1st premolar develops from _____ lobes
4
Man 2nd premolar develops from _______ lobes
5 (3 cusp) or 4 (2 cusp)
Man 1st premolar calcification
1.75-2yrs
Man 2nd premolar calcification
2.5 yrs
man 1st premolar enamel completion
5-6yrs
man 2nd premolar enamel completion
6-7yrs
man 1st premolar eruption
10-11yrs
man 2nd premolar eruption
11-12
man 1st premolar root completed
12-13
man 2nd premolar root completed
13-14yrs
Man 1st Premolar Cusps:
Li cusp is very small/large almost like a cingulum on a canine
_____ distance is similar to
canine
Mesiobuccal/distobuccal cusp ridge isthe same or slightly shorter than Mesiobuccal/Distobuccal cusp ridge
Large prominent, sharp ____ ______ only part that is in
occlusion. Contributes to
tearing and shearing like a
canine.
small
FL
mesiobuccal, distobuccal
Facial cusp
Man 2nd Premolar Cusps:
___ cusps, ___ F and ___ well developed Li cusps in first
type. The second type has
____ cusps with __F and ___Li
cusp
More surface area in
________- similar to molar
Larger more prominent
________ ______
Tooth resembles ______
because it has chewing or
grinding efficiency
3, 1, 2
2, 1, 1
occlusion
marginal ridges
molar
MANDIBULAR 1ST
PREMOLAR – O VIEW:
Resembles small ______
Mesio buccal and disto
buccal line angles are ____
and ____ respectively
Heavy buccal/lingual but small
buccal/lingual triangular ridge
Small/Big occlusal table
______ or ______ in
shape with sharp
convergence to the L
Well developed
______ _______.
Mesial is more cervical
than the distal
Smallest _______/_____
size difference of any
mandibular tooth i.e.
most round
______ posterior
tooth
canine
flat, round
buccal, lingual
small, triangular, diamond
marginal ridges
F-L / M-D
smallest
MANDIBULAR 1ST
PREMOLAR – F VIEW:
Well developed ____ _____ that results in large prominent
pointed buccal cusp and buccal ridge
where is the F cusp located?
mesial/distal cusp ridges are the same or slightly shorter than the mesial/distal cusp ridges
contact areas are higher on the mesial/distal than the mesial/distal
Curvatures of the cervical line
on the mesial and distal are
similar/different
middle lobe
F cusp is centered or slightly
mesial over the root
mesial, distal
distal, mesial
similar
MANDIBULAR 1ST
PREMOLAR – Li VIEW:
Prominent _______ _____
in the center lingual area
Due to ____ ______ most of the occlusal surface of crown is visible
Contact areas and marginal
ridges are ________
_________ groove is
present. Line of demarcation
between:
Root is more narrow on the
Buccal/Lingual
transverse ridge
lingual taper
pronounced
Mesiolingual, mesial buccal lobe and lingual lobe
lingual
MANDIBULAR 1ST
PREMOLAR – M VIEW:
F cusp is _____ over the
root
Crown is tipped to the
______
Prominent ______ ______
is visible
Small ____ cusp
Lingual height of contour is
in the ________ and facial
height of contour is in the
________
Strong prominent middle
_____
_____ ______ Groove
centered
lingual
transverse ridge
lingual
middle 1/3, cervical 1/3
lobe
mesio lingual
MANDIBULAR 1ST
PREMOLAR – D VIEW:
Crown tipped to the _______
Li height of contour is in
_______
Facial height of contour is
in ________
mesial/distal marginal ridge is
higher and flatter than
mesial/distal marginal ridge
No ________ ______
Distal root more convex/concave
lingual
middle 1/3
cervical third
distal, mesial
developmental groove
concave
two common forms of Man 2nd premolar:
3 cusp premolars appear more ______
2 cusp premolar appears ore ________
angular
rounded
Mandibular 2nd Premolar O
View:
____ cusp is the largest of
the two lingual cusps
This tooth is the only
premolar with a:
Marginal ridges are fairly
_______ and _____
Central pit and “___” shaped.
Central pit is slightly
towards the mesial/distal.
Occlusal table is _____
what are the 3 developmental grooves?
Central pit is midway
between:
Central pit is generally ___ to
Mesial and Distal pits
ML
lingual groove
prominent, even
y, distal
square
Mesial developmental, Distal
developmental, and Lingual developmental grooves
between the F cusp tip and
the Li surface
Li
MANDIBULAR 2nd
PREMOLAR – F VIEW:
Buccal cusp is shorter/longer. The cusp angle between the
cusp ridges is more acute/obtuse
_____ ________ contact
areas
Root is broader M-D/F-L and
root ends in an apex that is
sharp/blunt
shorter
obtuse
broad, symmetrical
M-D
blunt
MANDIBULAR 2nd
PREMOLAR – Li VIEW:
Li cusps are shorter/longer than the Li cusp on the first
premolar. Less of the
______ cusp is seen
ML/DL cusp is larger than the
ML/DL cusp
A Lingual _____ is present
and runs a short distance
Less root _________
Buccal to Lingual than in
first premolar
longer, buccal
ML, DL
groove
convergence
MANDIBULAR 2nd
PREMOLAR – M VIEW:
Tooth is wider __________ than 1st premolar
______ cusp is not as centered over the root and is shorter
Marginal ridge is at _____
angles to the long axis of
tooth
More/Less occlusal surface can
be seen
Slightly shorter/longer but sharper/blunter root
bucco lingually
facial
right
Less
longer, blunter
MANDIBULAR 2nd
PREMOLAR – D VIEW:
More/Less occlusal surface can be seen
Distal marginal ridge is at a
level lower than the M
marginal ridge
More
MANDIBULAR 2nd
PREMOLAR – 2 cusp type
height relationship between 2 cusps:
Is there a lingual groove?
Li cusp is same height
no, but there is a slight depression on the disto lingual
Mandibular 2nd Premolar
2 cusp type O:
The two cusp tooth is more
______ on the lingual than
the more square 3 cusp
Well developed ___ cusp
opposite the ____ cusp
rounded
Lingual, facial
How to tell between right and left man 1st premolars
flat mesio-lingual line angle
mesiolingual groove on the occlusal surface
mesial pit closest to cusp ridge
1st premolar vs canine:
premolar has ____ cusps
premolar has two distinct ____
premolar has a distinct ______ groove
2
pits
mesio-lingual
1st molars vs 2nd pre-molars
similar flat type broad ______ table
blunted ______ cusps
marginal ridges are similar_____ and _______
occlusal
broad
size, position
what is the 3rd most common impacted or congenitally missing tooth behind 3rd molars and Maxillary lateral incisors
mandibular 2nd premolar
the _______ molars must maintain the space for the permanent premolars to erupt
primary
Primary ____ molar maintains the space by keeping the permanent first molar
from drifting forward
2nd
The primary molars have larger M-D width than the mandibular premolars.
When the mandibular premolars come in the first molar moves ________
forward
Posterior teeth fracture
incidence:
Most common are _____ _______ specifically
the ______ cusps
b. Second most common are ______ _______ but in
some studies are the most common. Most commonly fractured are ________ and
________ cusps
c. Third are the ______ ________. For these, the _______ cusp is most commonly fractured
d. _____ ________ are least commonly fractured
mandibular molars, lingual
maxillary molars, mesiofacial, distolingual
maxillary premolars, buccal
mandibular premolars
Mandibular Premolar
Fracture Incidence:
mandibular molars:
maxillary molars:
maxillary premolars:
mandibular premolars:
other:
48%
28%
16%
6%
2%
