PreMolars Flashcards
Class Traits of Premolars that are similar to Anterior teeth
Crown Tapers narrower towards the CEJ
Crown tapers narrower towards the lingual
CEJ follows the same curvature but less pronounced
Roots taper apically and lingually
Distal contact is more cervical than mesial contact
What tooth in the mouth has a mesial contact that is more cervical than the distal?
Mandibular first premolar
what is the only premolar that is likely to have 2 lingual cusps?
Mandibular second premolar
Direction of marginal ridges in premolars?
Horizontal
Except: mandibular firs premolar that has a marginal ridge at an angle.
facial height of contour for premolars
Cervical third (but further away from the CEJ compared to mandibular first which has a crest of curvature very close to the CEJ)
Lingual Crest of curvature
middle third
proximal areas
located more cervical than anterior teeth crest of curvature and broader.
Mesial is always more occlusal than distal
Except: mandibular first that has a distal more occlusal than mesial
Crown outline shape for all premolars
Pentagon outline
Size of mesial and distal cost ridges
Mesial cusp ridge is shorter than distal cusp ridge.
length of cusps
buccal cusp is LONGER than lingual cusp
lingual cusp position
lingual cusp leans to the mesial side (important for determining left vs. right)
which marginal ridge is more occlusal in premolars?
Mesial marginal ridge is more occlusal than the distal marginal ridge. (Ex: mandibular 1st premolar)
from the occlusal view, the occlusal table is bound by what structures?
marginal ridges and cusp ridges.
from an occlusal view, a premolar is wider in what directions?
premolars are wider facia-lingual than messy-distal from an occlusal view
contact areas from an occlusal view
Mesial contact is more buccal
Distal contact is more towards the lingual but WILL NEVER extend to the lingual third
which embrasure space is larger when looking at an occlusal view
Lingual (because the crown is narrower towards the lingual)
between what two teeth is the largest embrasure space in the entire mouth?
largest embrasure in the entire mouth is between the maxillary lateral incisor and the canine
triangular ridges join to form what structure?
transverse ridges
what premolar doesn’t really have a central groove?
mandibular first premolar
Traits that differ mandibular premolars from maxillary premolars
Lingual tilt: mandibular premolar crown tilt lingually while maxillary crown are straight in the same axis as the root.
Buccal Ridge prominence: in mandibular teeth is less prominent than maxillary
Crown proportions: maxillary premolars are more rectangular and mandibular premolars are more closer to equal dimensions
which maxillary premolar is larger?
maxillary first premolar
which premolar has wide shoulders?
maxillary first premolar
which premolars has a mesial cusp ridge that is LARGER than the distal cusp ridge? this is very rare
Maxillary first premolar
between maxillary first and second premolars, which has the sharpest buccal cusp?
maxillary first
which premolar is known for having 2 roots?
maxillary first premolar
describe the roots of the first maxillary premolar
two roots / 1 buccal and 1 lingual / buccal root leans distal and is longer / lingual root is shorter and straight
on maxillary first premolar, which cusp is larger?
buccal cusp is noticeably larger than lingual cusp
on maxillary premolars, which direction does the lingual cusp point to?
mesial
what is the largest crown ration in the maxillary arch?
second premolar
what is the smallest crown ration in the maxillary arch?
maxillary central incisor
what is a distinguishing characteristic for maxillary first premolar?
it has a crown depression which is always on the mesial side. this concavity is not present on any other tooth
what is the lingual height of contour for maxillary premolars?
middle third
which premolar has a mesial marginal ridge?
maxillary first premolar
which premolar is the only premolar to have a mesial root depression more pronounced than a distal root depression?
maxillary first premolar
what is the only premolar that is likely to have 3 cusps?
mandibular second premolar
