Permanent Mandibular Premolars Flashcards
how many lobes are the mandibular first and second premolars derived from?
- first premolars - 4 lobes
- second premolars - 5 lobes; 3 buccal, 2 lingual
the mandibular first premolar has a long, well formed ____ cusp, and a small ____ lingual cusp
buccal, nonfunctioning
the mandibular first premolar resembles a ___ since only the buccal cusp is in ____
canine, occlusion
which of the two mandibular premolars is smaller?
the first premolar; this is opposite of the maxillary premolars
the second mandibular premolar has ___ well formed cusps; one large ___ cusp and two smaller ___ cusps
- 3
- buccal
- lingual
the mandibular second premolar is more like a small molar due to the _____
high horizontal marginal ridges
T or F:
the mandibular first and second premolars are true bicuspids
false
how does the mandibular first premolar resemble a canine?
- long sharp buccal cusp, only one in occlusion
- buccolingual measurement is smaller
- occlusal surface slopes lingually in cervical direction
- mesiobuccal cusp ridge is shorter than the distobuccal
- outline form of the occlusal resembles the canine
how does the mandibular first premolar resembe the second premolar?
- outline of crown and root from buccal are similar except for longer cusp
- mesial and distal contact areas are nearly the same level
- cervical line curvatures mesial and distal are similar
- tooth has more than one cusp
- *root of the first premolar is usually shorter than the second*
from the buccal aspect of the 1st mandibular premolars, form is nearly symmetrical ____
bilaterally
from the buccal aspect of the 1st mandibular premolars, ___ lobe is well developed with large pointed ___
middle, cusp
from the buccal aspect of the 1st mandibular premolars, ___ contact areas at nearly the same level
broad
from the buccal aspect of the 1st mandibular premolars, the shape is ____
trapezoidal
from from the buccal aspect of the 1st mandibular premolars, the cervical line has ____ curvature
very little
from the buccal aspect of the 1st mandibular premolars, the mesial outline is straight above the _____, and may show slight ____ to contact
cervical, concavity
from the buccal aspect of the 1st mandibular premolars, the tip of the ___ cusp is pointed and just ___ to center of crown
buccal, mesial
from the buccal aspect of the 1st mandibular premolars, the distal outline has slight ___ above the cervical line to contact area
concavity
from the buccal aspect of the 1st mandibular premolars, the root is usually 3-4mm ___ than the mandibular canine
shorter
from the buccal aspect of the 1st mandibular premolars, the buccal surface is more ___ than maxillary premolars
convex
T or F:
from the buccal aspect of the 1st mandibular premolars, you cannot see developmental depressions between the three lobes
false:
you can see developmental depressions between the 3 lobes
from the buccal aspect of the 1st mandibular premolars, a ___ ridge is present from cusp to cervical margin
buccal
from the lingual aspect of the 1st mandibular premolars, crown tapers toward the ___
lingual
from the lingual aspect of the 1st mandibular premolars, lingual cusp is ___
small
from the lingual aspect of the 1st mandibular premolars, it resembles a ___
canine
from the lingual aspect of the 1st mandibular premolars, mesial and distal surfaces can be seen due to ____
the taper to the lingual
from the lingual aspect of the 1st mandibular premolars, occlusal surface slopes to the ____ to the short lingual cusp
from the lingual aspect of the 1st mandibular premolars, most of the ____ surface can be seen
occlusal
from the lingual aspect of the 1st mandibular premolars, cervical part of the crown is ___, ___, and concavities are seen between ___ and ____
- narrow
- convex
- contacts
- cervical line
from the lingual aspect of the 1st mandibular premolars, contact areas and ____ are prominent and extend past _____
- marginal ridges
- narrow cervix
from the lingual aspect of the 1st mandibular premolars, lingual cusp, though small, is ___ and ___, and is in line with the _______ with mesial and distal _____ present on either side of the ridge
- sharp and pointed
- buccal triangular ridge
- occlusal fossae
describe the mesiolingual developmental groove of the lingual aspect of the 1st mandibular premolars
- boundary of the mesiobuccal lobe and the lingual lobe
- extends into the mesial fossa on the occlusal surface
- helps determine left from right
from the mesial aspect of the 1st mandibular premolars, the shape of the outline is ___
rhomboidal
from the mesial aspect of the 1st mandibular premolars, the tip of the buccal cusp is nearly ____ over the root
centered
from the mesial aspect of the 1st mandibular premolars, the convexity of the ____ outline extends past the root trunk
lingual
from the mesial aspect of the 1st mandibular premolars, the convexity of the ____ outline goes from cervical line with the crest near the _____
- buccal
- middle 1/3
from the mesial aspect of the 1st mandibular premolars, the crest on the lingual is near the ___ and may be in line with ____
- middle 1/3
- lingual border of root
from the distal aspect of the 1st mandibular premolars, distal marginal ridge is ___ than mesial with ___ lingual slope and may be at right angles to the ____
- higher
- less
- crown and root
from the distal aspect of the 1st mandibular premolars, most of the surface of the crown is ___, smooth with unbroken curve
convex
from the distal aspect of the 1st mandibular premolars, distal contact area is ____ than the mesial
broader
from the distal aspect of the 1st mandibular premolars, curvature of the cervical line is ___ as the mesial
about the same
from the distal aspect of the 1st mandibular premolars, surface of the root is more ___ than the mesial
convex
from the distal aspect of the 1st mandibular premolars, distal surface slopes ____ toward the lingual than the mesial
more gradually
from the occlusal aspect of the 1st mandibular premolars, most common shape is ____. other shape is ___
- diamond; this is similar to the mandibular canine
- circular
T or F:
some 1st mandibular premolars will be like mandibular 2nd premolars from the occlusal aspect
true
T or F:
the mandibular 2nd premolar resembles the 1st premolar from the lingual view
false:
they resemble each other only from the buccal view
what are the differences between the 1st and 2nd mandibular premolars?
2nd premolar is…
- less pronounced buccal cusp
- larger and better developed
what are the 2 common forms of the mandibular 2nd premolar?
- 3-cusp (more angular)
- 2-cusp
the mandibular 2nd premolar has a single root that is ___ and ___ than the 1st premolars root
larger and longer
T or F:
you may see a deep developmental groove lingually on the mandibular 2nd premolar
false:
deep developmental groove is on the buccal surface
from the mesial aspect of the mandibular 2nd premolar, the crown and root are ___ bucco-lingually than the 1st premolar
wider
from the mesial aspect of the mandibular 2nd premolar, the buccal cusp is not so centered over root and is ____ than the 1st premolar
shorter
from the mesial aspect of the mandibular 2nd premolar, there is a ____ lingual lobe development when compared to the 1st premolar
greater
from the mesial aspect of the mandibular 2nd premolar, the marginal ridges are at ____ to long axis of the tooth
right angles
from the mesial aspect of the mandibular 2nd premolar, you will see ____ occlusal surface when compared to the 1st premolar
less
is there a mesiolingual developmental groove seen from the mesial aspect of the mandibular 2nd premolar?
no
from the mesial aspect of the mandibular 2nd premolar, the root is ___, with a slight ___ on mesial surface when compared tothe 1st premolar
- longer
- convexity
from the mesial aspect of the mandibular 2nd premolar, the apex is more ___ when compared to the 1st premolar
blunt
from the distal aspect of the mandibular 2nd premolar, it is similar to mesial except ___ of the occlusal surface can be seen
more
from the distal aspect of the mandibular 2nd premolar, marginal ridge is at a ___ level than the mesial
lower
crowns of all posterior teeth dip ___ as part of the ____
- distally
- curve of spee
from the occlusal aspect of the mandibular 2nd premolar, 3-cusp type appears more ___ from lingual to buccal cusp ridges, and the 2-cusp type appears more ___
- square
- round
from the occlusal aspect of the mandibular 2nd premolar, the buccal cusp is the largest, followed by the ___ and ___
- mesio-lingual
- disto-lingual
from the occlusal aspect of the mandibular 2nd premolar, triangular ridges converge in a central pit and is ___ shaped
Y
from the occlusal aspect of the mandibular 2nd premolar, the central pit is located midway between the ___ and the ____
- buccal cusp ridge
- lingual margin of the occlusal surface
from the occlusal aspect of the mandibular 2nd premolar, mesial developmental groove goes ____ and ends in ___
- mesiobuccally
- mesial triangular fossa
from the occlusal aspect of the mandibular 2nd premolar, the distal developmental groove goes ___ and is ___
- disto-buccally
- shorter
from the occlusal aspect of the mandibular 2nd premolar, the mesiolingual cusp is ___ mesiodistally than distolingual cusp, so that the lingual developmental groove is ___ to the center of the crown
- wider
- distal
from the occlusal aspect of the mandibular 2nd premolar, will see ____ radiating from developmental grooves
supplemental grooves
from the occlusal aspect of the mandibular 2nd premolar, on occasion, a groove may cross over a ____
marginal ridge
from the occlusal aspect of the mandibular 2nd premolar, the outline is ___ lingual to the buccal cusp ridges
round
from the occlusal aspect of the mandibular 2nd premolar, mesiolingual and distolingual line angles are ____
rounded
from the occlusal aspect of the mandibular 2nd premolar, there is ___ well-develped lingual cusp opposite to the buccal cusp
one
describe the central developmental groove of the mandibular 2nd premolar
- straight
- crescent shape
- ends are mesial and distal fossae
- may have developmental pits in these terminations
- may have a developmental depression crossing the distolingual cusp ridge
the pulp cavity of the mandibular 1st premolar is similar to the ____ with usually ___ canal
- mandibular canine
- one
1st premolar may have prominent pulp horn on ____
buccal
1st premolar has ___ pulp chamber
large
2nd premolar has ___ pulp chamber than the 1st premolar
larger
2nd premolar has ___ prominent pulp horns than the 1st premolar
more
pulp chambers of 1st and 2nd mandibular premolars are similar from what aspect?
mesio-distal
from the mesial aspect of the mandibular 1st premolar, the distance from cervical line to lingual root is about ___ that of the buccal root
2/3
from the mesial aspect of the mandibular 1st premolar, describe the mesiobuccal lobe development
it is prominent with a prominent marginal ridge
from the mesial aspect of the mandibular 1st premolar, is a mesiolingual developmental groove seen?
yes
from the mesial aspect of the mandibular 1st premolar, which ridge parallels the marginal ridge?
triangular ridge
from the mesial aspect of the mandibular 1st premolar, the cervical line curves ___ by about 1mm, or it may be ___
- occlusally
- straight across
from the mesial aspect of the mandibular 1st premolar, the surface is smooth except for the ____
developmental groove
from the mesial aspect of the mandibular 1st premolar, what is just below the contact area?
there is a concave area going to the cervical line
from the mesial aspect of the mandibular 1st premolar, the mesial surface of the root is smooth from ___ to the ___. a developmental groove or even a shallow depression may end in a ___
- buccal
- center
- bifurcation at the apical 1/3
characteristics common to mandibular 1st and 2nd premolars:
____ is most of the bulk of the tooth
middle buccal lobe
characteristics common to mandibular 1st and 2nd premolars:
___ buccal ridge
prominent
characteristics common to mandibular 1st and 2nd premolars:
rounded, yet prominent, ___ and ___ line angles
mesiobuccal and distobuccal
characteristics common to mandibular 1st and 2nd premolars:
broad contact areas just lingual to ___ line angles, with ___ contact area being broadest
- buccal
- distal
characteristics common to mandibular 1st and 2nd premolars:
crown converges from contact area rapidly to ___
lingual
characteristics common to mandibular 1st and 2nd premolars:
well developed ___ ridges
marginal
characteristics common to mandibular 1st and 2nd premolars:
ligual cusp is ___
small
characteristics common to mandibular 1st and 2nd premolars:
buccal triangular ridge on occlusal is ___, lingual triangular ridge is ___
- heavy
- small
characteristics common to mandibular 1st and 2nd premolars:
two depressions on occlusal surface are the ___ and ___
mesial and distal fossae
characteristics common to mandibular 1st and 2nd premolars:
most forms have a ___ which makes the mesial contact area small so that it contacts with canine
mesiolingual developmental depression groove
characteristics common to mandibular 1st and 2nd premolars:
mesial fossa is ___ in form from which the mesial developmental groove goes ___
- linear
- buccolingually
characteristics common to mandibular 1st and 2nd premolars:
distal fossa is ___ in form and may have a distal developmental groove that is ___ shaped
- circular
- crescent
characteristics common to mandibular 1st and 2nd premolars:
most of the buccal surface can be seen from the ___ view
occlusal
from the buccal aspect of the mandibular 2nd premolar, the ___ cusp is shorter compared to the 1st premolar
buccal
from the buccal aspect of the mandibular 2nd premolar, the buccal cusp shows ___ angulation than the 1st premolar
less
from the buccal aspect of the mandibular 2nd premolar, contact areas appear ___ due to ___
- higher
- shorter cusp
from the buccal aspect of the mandibular 2nd premolar, the root is ___ mesiodistal than the 1st premolar
broader
from the buccal aspect of the mandibular 2nd premolar, the apex of the root is more ___ than the 1st premolar
blunt
from the lingual aspect of the mandibular 2nd premolar, lingual lobes have ___ development, and the cusps are ___
- more
- longer
from the lingual aspect of the mandibular 2nd premolar, more or less of the occlusal surface can be seen compared to the 1st premolar?
less occlusal surface is seen in the 2nd premolar
from the lingual aspect of the mandibular 2nd premolar, in the 3-cusp type, which cusps are seen? which is the largest/longest of the two that are visible?
- mesiolingual and distolingual cusps
- mesiolingual is largest/longest
from the lingual aspect of the mandibular 2nd premolar, in the 2-cusp type, the ___ cusp is as long as the 3-cusp type and may show a ___ where the lingual cusp ridge joins the ___
- lingual
- developmental depression
- distal marginal ridge
from the lingual aspect of the mandibular 2nd premolar, the root is wide, but not as wide as the ___ portion, and has ___ lingual convergence than the 1st premolar
- buccal
- less
