Oral Anatomy: Premolars

Question 1

Which is the largest of all premolars?

Answer 1

Max first PM

Question 2

Which premolar has a prominent buccal ridge?

Answer 2

Max first PM

Question 3

T/F: The max first premolar is the only permanent tooth with a distal cusp ridge greater than the mesial cusp ridge.

Answer 3

False

Only tooth with mesial cusp ridge greater than distal

Question 4

Which tooth has a very prominent mesial marginal ridge groove?

Answer 4

Max first PM

Question 5

For a max first PM, the occlusal shape is ________ and the proximal shape is ________.

Answer 5

hexagonal; trapezoidal

Question 6

T/F: The max first PM has a prominent central pit.

Answer 6

False

Long central groove with mesial and distal pits

Question 7

Which way do the two cusps tilt on a max first PM?

Answer 7

Buccal - distal
Palatal - mesial

makes sense because mesial cusp ridge of buccal cusp > distal cusp ridge

Question 8

T/F: The buccal cusp of the max first PM is taller than the palatal cusp.

Answer 8

True

Question 9

T/F: In the max 2nd PM, the distal cusp ridge is greater than the mesial cusp ridge.

Answer 9

True

Question 10

T/F: The max 2nd PM has a more prominent buccal ridge than the max 1st PM.

Answer 10

False

Question 11

What is the major difference of the occlusal table of a max 2nd PM versus the max 1st PM?

Answer 11

2nd PM has a shorter central groove and has more supplemental grooves (wrinkled appearance)

Question 12

T/F: The buccal cusp of the max 2nd PM is taller than the palatal cusp.

Answer 12

False

Equal in height, unlike max 1st PM

Question 13

Which is the smallest of all the premolars?

Answer 13

Mand 1st PM

Question 14

A unique characteristic of the mand 1st PM is its prominent ________.

Answer 14

mesio-lingual groove

Question 15

Which marginal ridge of the mand 1st PM is most prominent?

Answer 15

Distal

Question 16

On a mand 1st PM, the occlusal shape is _________ and the proximal shape is _________.

Answer 16

diamond; rhomboidal

Question 17

Which is the only posterior tooth with a lingually tilted occlusal table?

Answer 17

Mand 1st PM

Question 18

T/F: The mand 1st PM has a long central groove.

Answer 18

False

Max 1st PM has long central groove

Mand 1st PM has no central groove - transverse ridge splitting mesial and distal fossae

Question 19

Which is the most congenitally missing premolar?

Answer 19

Mand 2nd PM

Question 20

T/F: The gingival papilla between the first and second mand PM is the shortest.

Answer 20

True

Question 21

T/F: The lingual surface of the mand 2nd PM is narrower than the mand 1st PM.

Answer 21

False

Wider M-D

Question 22

The mand 2nd PM is the only premolar with ____ lobes.

Answer 22

Five

Question 23

What is the occlusal shape of a mand 2nd PM?

Answer 23

Square

Question 24

Which occlusal configuration is the most common in mand 2nd PM?

Answer 24

Y - 3 cusps with a single central pit

buccal > ML > DL

Question 25

What are the two less common occlusal configurations of mand 2nd PM?

Answer 25

H and U

H has shorter central groove

U has crescent shaped central groove

Question 26

T/F: The buccal cusp of the mand 2nd PM is taller than the lingual cusps.

Answer 26

False

Shorter

Question 27

Which root is likely to have its apex closest to the mental foramen?

Answer 27

Mand 2nd PM

Question 28

Of the two mand premolars, which has the longer root?

Answer 28

Mand 2nd PM