Pre-molars

Question 1

give the FDI notation for the upper right 1st pre molar

Answer 1

14

Question 2

give the FDI notation for the upper right 2nd pre molar

Answer 2

15

Question 3

give the FDI notation for the upper left 1st pre molar

Answer 3

24

Question 4

give the FDI notation for the upper left 2nd pre molar

Answer 4

25

Question 5

give the FDI notation for the lower left 1st pre molar

Answer 5

34

Question 6

give the FDI notation for the lower left 2nd pre molar

Answer 6

35

Question 7

give the FDI notation for the lower right 1st pre molar

Answer 7

44

Question 8

give the FDI notation for the lower right 2nd pre molar

Answer 8

45

Question 9

which surface of the tooth is lower/shorter in height? the palatal surface or the buccal

Answer 9

palatal surface is lower than the buccal

Question 10

what is a key feature in the upper first pre molar than contacts the distal surface of the canine?

Answer 10

canine fossa

Question 11

which tooth does the presence of the canine fossa appear? and what surface is it on?

Answer 11

canine fossa is present on upper 1st pre molar and indicates the mesial side of this tooth. It contacts the distal surface of the upper canine.

Question 12

which pre molar has a development groove present in the enamel and what does this indicate?

Answer 12

developmental groove is present on the upper 1st pre molar and indicates the mesial marginal ridge.

Question 13

on the Occlusal surface of the upper 1st pre molar, which cusp is wider & higher? the buccal cusp or the palatal?

Answer 13

the buccal cusp is wider and higher

Question 14

on which tooth is there clear mesial displacement of the lingual cusp?

Answer 14

upper 1st pre molar (also slight displacement present on upper 2nd pre molars)

Question 15

what percentage of upper 1st pre molars have two roots?

Answer 15

> 50%

Question 16

what surface(s) do the 2 roots (if present) sit on the upper 1st pre molar?

Answer 16

1 buccal and 1 lingual
(bifurcation)

Question 17

what is a clear differences between the upper 1st pre molar and upper 2nd?

Answer 17

2nd pre molar is
- smaller
- has no developmental depression
- only 15% have 2 roots
- cusps are almost equal height on the 2nd pre-molar
- distal marginal ridge is more cervical

Question 18

what is a key feature of the distal marginal ridge on the 2nd upper pre molar?

Answer 18

the distal marginal ridge is more cervical (deeper)

Question 19

is the buccal surface of the lower first pre molar strongly inclined lingually or buccally?

Answer 19

lingually

Question 20

how can you tell which surface is mesial and distal in the lower first pre molars?

Answer 20

the small groove runs from mesial pit further to the cervical line

Question 21

for mandibular pre molars, does the cusp tilt lingually from the root or does the cusp go straight up?

Answer 21

tilts lingually from the root. Maxillary pre molars, the cusp goes vertical from root.

Question 22

how many cusps do pre molars have? (approx.)

Answer 22

2-3

Question 23

when there are 3 cusps on the lower 2nd pre molar, which cusp is the largest? mesio-lingual cusp or the disco-lingual cusp

Answer 23

the mesio-lingual cusp is the larger one. (mesial surface)

Question 24

what is a key difference between the lower 1st and 2nd pre molars?

hint* think height of cusps

Answer 24

greater difference in the height of the buccal and lingual cusp in the first pre molar.

the 2nd pre molar, cusps are more similar in height

Question 25

what is a key difference between the shape of the lower and upper pre molars?

Answer 25

lower are more rounded and upper are oval.