Permanent Premolars Anatomy Flashcards
Numbers of premolars
Max = # 4, 5, 12, 13
Mand = # 20, 21, 28, 29
Permanent premolars take the place of _____ and are therefore ______ teeth
Deciduous molars
Succedaneous
The first premolars assist :
The canines in shearing or cutting food morsels
All upper and lower premolars….
Support corners of mouth and cheeks to keep them from sagging
Function with molars to masticate foods and maintain the vertical dimension of the face between the nose and the chin
The buccal surfaces of all premolars develop from ________ facial lobes evidenced by _______, ______ depressions separating the buccaneers ridge of the facial surface of the crown from the mesial and distal portions
3, 2, vertical
The lingual surfaces of most premolars develop from ____ lingual lobe
In premolars, this forms ___ lingual cusp
One, one
When compared to mandibular premolars, max 1st and 2nd premolars :
Are much more alike
Have buccal and lingual cusps that are nearly equal in size
Are more oblong in the B-L dimension
Which is the widest premolar?
Max 1st
On the buccal cusp of the max 1st premolar, the mesial cusp ridge is ___ than the distal cusp ridge
This is unique to this permanent tooth and _____
Longer
Primary canines
On the max 1st PM, the buccal cusp tip is placed _____ of the RAL
Slightly distal
On the max 2nd PM, the cusp tip is set to the ___
Mesial cusp ridge is _____ than distal
Mesial
Shorter
_______ (max/mand; 1st/2nd) PM is more likely to have two roots
Max 1st
On the max 1st PM, the lingual cusp is _____ and bends towards the ______
The lingual root is ____ than buccal root
Shorter, mesial
Shorter
On max 2nd PM from a facial view, the lingual cusp is _____ than the lingual cusp of 1st meaning that the cusps are _____
The lingual cusp is offset to the ___
Longer, more nearly equal in size
Mesial
On max 1st PM, there is a prominent ______ located ___ to the contact area
Mesial concavity, cervical
From a proximal view of the max 1st PM, the _____ cusp is noticeably longer than the _____ cusp
Buccal, lingual
On the max 1st PM, what is always present in the proximal view?
Mesial marginal ridge groove
The max 1st premolar is considered very brittle because:
How does this relate to the canine?
Mesial marginal groove, mesial concavity, two spindly roots
Robust canine to protect weaker premolar
The max 2nd PM from the proximal view has ____ root, no _______, no_____, and buccal and lingual cusps ______
1, mesial concavity, mesial marginal groove, nearly equal in size
A triangular ridge is any ridge that
Descends rom the cusp tip of a posterior tooth towards the central part of the occlusal surface
A transverse ridge is
The unions of two triangular ridges crossing transversely across the surface of a posterior tooth
An inclined plane is
The sloping area found between two cusp ridges
The max 1st PM from an occlusal view has a lingual cusp offset to the _____
A long central developmental groove that runs ______, crosses transverse ridge and ends in ______ in the triangular fossae
Mesial
Mesiodistally
Pits
The mesial marginal ridge groove on the max 1st premolars makes the central groove appear
Longer
In comparison to the max 1st PM, the max 2nd PM has a central groove that is _______
Line angles that are ______
Lingual cusp offset to the_____ (as much, not?)
Does this tooth have a mesial marginal groove?
Shorter and more irregular
More rounded
Mesial, not as much
NO
Buccal ridge is more prominent on the ______ max PM than the ___
1st, 2nd
Max 1st PM outline is _____ than the 2nd PM
More asymmetrical
Length of the central groove of max _____ PM is longer than on the ____
1st, 2nd
Does the max 1st or 2nd PM have more supplemental grooves?
2nd
Do the mand or max PM vary more in shape?
Mand
The crown on the mand PM appears to be _____ form a proximal view
Tilted o the lingual
“Buccal cusp larger than lingual”
More so on mand or max PM?
mand
(Mand/max)_______ PM closer to square shape
Mand
All premolars have ______ width greater than _______
Buccolingual, mesiodistal
Mand 1st PM has characteristics of _____
Mand 2nd PM has characteristics of ____
Canine
Molar
On which tooth is the mesial contact area more cervical than distal ??? *****only 1
Mand 1st PM
On mand 1st PM, the cusp tip is _____ to the midline
Slightly mesial
Buccal cusps on which mand PM are sharper?
1st
What is the hallmark of the mand 1st PM?
Mesiolingual developmental groove and prominent transverse ridge
From the lingual view of the mand 1st PM, what can be seen?
Entire occlusal surface
Most of mesial distal surfaces
What is the only premolar & posterior tooth to have a mesial marginal ridge more cervically located than its distal marginal ridge?
Mand 1st
The buccal cusp tip on mand 1st PM is ______ over root
Tip of lingual cusp is ____ with lingual border of the root
Centered
In line
On which mand PM does the crown tip more lingually?
1st
The root on the mand 1st PM is
Short but often has a deep developmental groove ON MESIAL
From a proximal view, which ridge is more occlusal on the mand 1st PM?
Distal marginal ridge
Which surface makes up the bulk of the occlusal view on the mand 1st PM?
Buccal
The mand 1st PM has more bulk in the distal or mesial half?
Distal
Which mand PM is larger? Which has a longer root?
2nd, 2nd
Which PM can exist as either a 2 or 3 cusp type ?
Which type occurs more often?
Mand 2nd PM
3 cusp
The buccal cusp tip is more blunt on which mand PM?
2nd
When the mand 2nd PM has 2 lingual cusps, which is wider and longer?
Mesiolingual
Does the mand 2nd PM have a ML developmental groove?
Does the 1st?
No
Yes
Marginal ridges (from M aspect) on the ____ mand PM is more horizontal than the ____
2nd, 1st
From a distal aspect on a 3cusp type mand 2nd PM, how many cusps are visible?
The crown is tipped _____ so that more of the ______ surface is seen from the _____ than _____
All 3
Distally, occlusal, distal, mesial
What is the shape of the 3 cusp mand 2nd PM? (O)
What shape do the developmental grooves from on occlusal surface ?
Square
Y* shaped
Which PM is the only one with a central fossa?
3 cusp mand 2nd PM
What is the shape of the 2 cusp type mand 2nd PM? (O)
What is the shape of the central groove?
Round with some lingual convergent on M/D
Crescent shaped ( convex towards L)
Groove patterns on the 2 cusp mand 2nd PM can be
H or U* shaped
Does the 2 cusp mand 2nd PM have a lingual groove?
No
What is the shape of the max 1st PM (O)?
Hexagonal
