Mandibular 2nd Pre-molar Arch Traits

Question 1

at what age do they erupt?

Answer 1

11-12 years

Question 2

at what age is the root completed?

Answer 2

12-14 years

Question 3

what are the 2 forms and characteristics of them

Answer 3

1. Bicuspidate: has 2 cusps that are Buccal and Lingual

2. Tricuspidate: has 3 cusps that are Buccal, Mesial-Lingual, and Distal-Lingual

Question 4

Heights of contour from buccal view

Answer 4

mesial: Junction of occlusal and middle 1/3
distal: middle 1/3

Question 5

Which cusp is more developed from the lingual view?

Answer 5

the lingual cusp

Question 6

Is there a developmental groove in the bicuspid?

Answer 6

no

Question 7

order of size of the 3 cusps from tricuspid

Answer 7

B>ML>DL

Question 8

number of roots?

Answer 8

one

Question 9

how many cusps can be seen from the mesial view?

Answer 9

2 out of 3

Question 10

From the mesial view why are you unable to see the DMR?

Answer 10

because there is a high MMR

Question 11

From the distal view how many cusps can be seen?

Answer 11

all 3 because the DMR is relatively low

Question 12

Height of Contour from distal view

Answer 12

buccal: cervical 1/3
Lingual: Middle 1/3

Question 13

From the occlusal view, how are the proximal surfaces oriented?

Answer 13

parallel

Question 14

What letter does the bicuspid groove create?

Answer 14

a H or U

Question 15

what letter does the tricuspid groove create?

Answer 15

a Y