posterior tooth anatomy

curvature of the CEJ on (mesial/distal) is greater than (mesial/distal). this is characteristic of most teeth. what tooth has the greatest CEJ curvature?

mesial, distal

mesial of the maxillary central incisor

what premolar has 2 roots?

maxillary 1st (#5, #12)

most teeth have their buccal cusp tip offset to the (mesial/distal), with the exception of ____.

mesial

exception: maxillary 1st premolar (5,12). this is the only tooth where the MB ridge is longer than the DB ridge

on a maxillary first premolar, what root is longer?

buccal root is longer than the lingual root

what two features are unique to the mesial aspect of the maxillary first premolar?

mesial developmental depression on crown that extends down to root, restorative challenge

mesial marginal developmental groove*

on most teeth, the deeper root depression is on the (mesial/distal) aspect. what tooth breaks this rule?

most teeth: distal is deeper

exception: maxillary 1st PM (5,12), mesial depression is deeper

the occlusal table of what type of teeth are wider bucco-lingually than mesio-distally?

premolars and molars

how many canals will a maxillary 1st PM (5,12) have relative to its roots?

max 1st PM (5,12) will have 1-2 roots (usually 2) but will ALWAYS have 2 canals

compare the difference in cusp heights between a maxillay 1st PM (5,12) and a maxillary 2nd PM (4,13)

maxillary 1st PM (5,12) have a more noticeable difference in cusp heights, even tho the lingual cusp is shorter on both

the distal marginal ridge on most teeth is more (cervical/occlusal) in comparison to the mesial marginal ridge. what is the exception?

cervical

mandibular 1st PM (21,28)

what tooth has a wrinkly looking occlusal table?

maxillary 2nd PM (4,13)

which is the smallest premolar?

mandibular 1st PM (21,28)

what is the tooth where the interproximal contacts are reversed significantly? what does this mean in the context of that tooth

mandibular 1st PM (21,28)

this means the distal contact is more occlusal than the mesial contact (more cervical)

in line with the mesial marginal ridge being lower than distal

what is a distinguishing feature on the lingual aspect of the mandibular first premolar?

mesiolingual developmental groove

between the mesial marginal ridge and lingual cusp

in what arch do the premolars tilt lingually?

mandibular

because of the mesiolingual groove, the mesial marginal ridge of the _____ slopes more cervically.

mandibular 1st PM (21,28)

what tooth has an underdeveloped lingual cusp?

mandibular 1st PM (21,28) hence the steeper axial inclination

the mesiolingual groove on the ____ contributes to the tooth being wider buccolingually on the (mesial/distal) from the occlusal view

mandibular 1st PM (21,28)

distal

what premolar has the most prominent transverse ridge?

mandibular 2nd PM (21,28) “snake-eyes”

what tooth has different occlusal variations? what are they

mandibular 2nd PM (20,29) can have 2 or 3 cusp type

from how many lobes is a md. 1st PM formed from?

4-5, 5 if its the 3-cusp type

what is a characteristic feature on the lingual surface of a mandibular 2nd PM (20,29)?

lingual groove if its a 3-cusped toothcompa

compare the heights of the cusps on a 3-cusped mandibular 2nd PM

B > ML > DL

where is the transverse ridge located on the occlusal surface of a 3-cusped mandibular 2nd PM (20,29)?

it doesn’t have one

in a maxillary premolar, what anatomical feature is centered over the root?

central groove (because theres no lingual crown tilt)

in a mandibular premolar, what anatomical feature is centered over the root?

buccal cusp (bc of lingual tilt)

compare the crown sizes of a maxillary 1st and 2nd PM

maxillary 1st > maxillary 2nd

compare the crown sizes of a mandibular 1st and 2nd PM

mandibular 2nd > mandibular 1st

what tooth has the greatest root to crown ratio in the maxillary arch?

maxillary second premolar (4,13)

compare the occlusal outline form of a mandibular 1st molar (19,30) and a mandibular 2nd molar (18,31).

1st: pentagonal

2nd: rectangular what

what tooth has the largest M-D dimension of any tooth?

mandibular 1st molar (19,30)

what is the largest tooth overall in the mandibular arch?

mandibular 1st M (19,30)

from which aspect (buccal/lingual) can you see 5 cusps on a mandibular 1st M (19,30), why?

buccal

because the buccal cusps are more flat than the lingual cusps

compare the cusp sizes on a mandibular 1st molar (19,30)

MB > ML > DL > DB > D

compare the cusp heights of a mandibular 1st M (19,30)

ML > DL > MB >DB > D

what cusps are visible form the lingual aspect of the mandibular 1st M (19,30)

3: ML, DL, D

the buccal grooves on a mandibular second monalr (18,31) make it look like a

heart w/ mesial cusp slightly taller

compare the cusp heights of a mandibular second molar (18,31)

ML > DL > MB > DB

(they are equal in size hence the + appearance)

what way does the crown of a mandibular 2nd molar (18,31) taper if you’re looking at it from the occlusal view?

tapers distolingually what

what kind of mandibular molar has a wider root spread with more curved roots?

mandibular 1st molar (19,30)

the crowns of (maxillar/mandibular) molars are wider BL than MD

maxillary

mandibular are wider MD than BL

from a proximal view, (maxillary/mandibular) molars crowns have a lingual tilt relative to the root trunk

mandibular

maxillary are more centered

what is the most commonly impacted tooth>

third molar

what furcations does a maxillary molar have?

3 furcations: B, M, D

how many furcations do mandibular molars have?

2, midbuccal, midlingual

how many furcations does a maxillary premolar have?

2, middle of mesial, middle of distal

compare the root lengths of a maxillary 1st and 2nd molar (3,14) (2,15)

P > MB > DB

compare the cusp heights of a maxillary first molar (3,14)

ML > MB > DB > DL > 5th cusp

compare the cusp heights of a maxillary first molar (3,14)

ML > MB > DB > DLwhat

what pattern of crown length do maxillary molars follow as you go towards the posterior?

crowns get smaller

first molar longest crown length, third molar shortest crown length

what is the widest tooth in the maxillary arch

maxillary first molar (3,14)

the proximal and buccal outline form of all 3 maxillary molars is

trapezoidal

the occlusal outline form of the 3 maxillary molars are

1st and 2nd: rhomboid

3rd: heart-shaped

the buccal groove of the maxillary ____ molar is almost centered, and this groove migrates (mesially/distally) as you go to the back of the mouth

first

distally

how many cusps are visible from the lingual aspect of the maxillary 1st molar (3,14)

3: ML, DL, Carabelli how man

how many roots are visible from the mesial vs. distal aspects of a maxillary first molar (3,14)?

mesial: 2

distal: 3

what ridges form the oblique ridge of a maxillary 1st molar? (3,14)

ML, DB

compared to the maxillary first molars, maxillary second molars have (more/less) root flare

less, theyre straighter

compare the cusp sizes and lengths on a maxillary second molar

(ML > MB > DB > DL)

cusp heights also follow this

what cusp on a maxillary 2nd molar is not included in the primary cusp triangle?

distolingual

the oblique ridge of a maxillary 2nd molar is formed by

ML and DB triangular ridges

what is the widest crown buccolingually?

maxillary first molar