final Premolars Flashcards
most premolars have how many cusps? exception?
have 2 cusps; buccal and lingual
*Ex: 2nd man CAN have 3; buccal, mesiolingual and distolingual
mesial distal marginal rdiges are normally _____ for premolars? exception?
normally horizontal
*Ex: mand 1st premolar has a 45 degree MESIAL marginal ridge
mesial contacts are typically _____ and distal are typically ______? exception?
mesial are typically are the junction (more occlusal) and distal typically more cervical in the middle 3rd
*Ex: mandibular 1st premolar mesial contact is more cervical due to 45% angle of mesial marginal ridge
both mesial and distal contacts are more lingual or buccal?
buccal
facial shape of premolars?
pentagonal
occlusal outline of maxillary premolars?
trapezois
occlusal outline of mandibular premolars?
rhombus
the buccal cusp tip is ____ to the mid-line root axis? exception?
mesial
*Ex: max 1st premolar buccal cusp is distal to midroot axis
mesial cusp ridge of buccal cusp is____ the distal cusp ridge? exception?
mesial cusp ridge of buccal cusp is SHORTER than the distal cusp ridge
*Ex: maxillary 1st premolar mesial ridge is longer
mesial marginal ridges are more ____ than their distal marginal ridges? exception?
mesial marginal ridge more OCCLUSAL than distal
*Ex: mandibular 1st premolar mesial marginal ridge is cervical
premolars are wider ___ then ____
wider facialingually than mesiodistally
the apical 3rd portion of roots bend?
distally
all premolars taper towards the lingual or facial? exception?
LINGUAL
*Ex: 3 cusp mandibular 2nd premolar (bc they have two lingual cusps making it larger)
mandibular lingual cusps are shorter or longer than maxillary lingual cusp?
shorter
maxillary lingual cusps are distal or lingual to root axis?
mesial
both maxillary premolars have what root depressions?
mesial AND distal
what tooth has the mesial root depression spreading up through the crown?
maxillary 1st premolar due to bifurcated root
** what is the only tooth that has a buccal cusp tip distal to the root and the mesial cusp ridge is taller?
maxillary 1st premolar
angles of buccal cusps for maxillary and mandibular?
max 1= 105
max 2= 120-125
mesial marginal ridge grooves are almost always present on?
maxillary 1st premolars
buccal ridges are more prominent on maxillary 1st or 2nd premolars?
max 1st premolar
buccal cusp tip is mesial or distal to the root on 2nd max premolar?
mesial
Max 1st is distal
angles of buccal cusps for mandibular 1st and 2nd premolar?
mand 1= 110
mand 2= 130
what is unique about the mandibular 1st premolar lingual cusp?
WAY SMALL and nonfunctional (think about 45 degree angle again)
**mesial lingual groove on the mandibular 1st premolar separates?
the mesial marginal ridges and lingual cusp
the second mandibular 3 cusp premolars have a _____ groove separating the two lingual cusps
lingual groove
what premolar is LEAST LIKELY to have root depressions (mesial)?
mandibular 2nd premolar
what tooth has a “mesiolingual corner”?
2nd mandibular premolars