4 and 13: maxillary 2nd PM

Question 1

4 types embrasures

Answer 1

from incisal/occlusal view:

1. facial
2. lingual

from facial/lingual view:

3. gingival
4. incisal (only anteriors)

Question 2

what embrasures are seen from incisal/occlusal view

Answer 2

1. facial: one point to contact, one point to each tooth, flat surface against lip/cheek
2. lingual: same but flat surface is toward the palate

Question 3

embrasures see from lingual or facial view

Answer 3

• gingival: from contact up to gum

- incisal: only anteriors, from contact down – just air

Question 4

succedaneous teeth

Answer 4

-4 and 13 (2nd max PM) replace maxillary primary 2nd molars

Question 5

root length, 5/12 vs 4/13

Answer 5

4/13 longer root

Question 6

4/13 buccal view

Answer 6

• coronal outline similar to maxillary 1st PM but less defined, less cervical taper, more rounded buccal cusp
• outline form broadest at the contact area (middle 1/3)
• distal slope is longer than mesial (opposite to 1st PM)

Question 7

4/13 root

Answer 7

• conical, smoothly convex adn often longer than root of 5/12
• tapers to lingual (as does crown)
• mesial root depression might be present but does not continue to crown
• distal depression more likely than mesial
• usually no bifurcation

Question 8

4/13 from lingual view

Answer 8

• tapers
• more defined lingual cusp than 1st PM max
• distal marginal ridge is more cervical than mesial marginal ridge

Question 9

way to tell left from right for 2nd max PM

Answer 9

• look from the lingual at the distal adn mesial marginal ridges
• DMR is closer to CEJ than MMR
• MMR closer to occlusal surface than DMR
• from mesial, you see less of occlusal surface
• from distal, you see more occlusal surface

Question 10

mesial view of 4/13

Answer 10

• MMR is more occlusally located, so you see less of occlusal surface than from distal
• F and L HOC are at jxn of middle and cervical 1/3’s
• F adn L nearly equal in height

Question 11

facial adn lingual HOC on 4/13

Answer 11

at jxn of middle and cervical thirds

• F slightly more cervical
• L more to middle

Question 12

distal view of 4/13

Answer 12

• you can see more of occlusal table bc DMR more cervical than MMR
• less pronouced CEJ than mesial

Question 13

CEJ on 4/13, distal vs mesial

Answer 13

more pronounced curve on mesial

Question 14

occlusal view of 4/13

Answer 14

• more of an oval
• occlusal grooves - more wrinkled looking, can vary, no MMR groove
• less angled
• cusp slopes parallel to each other
• both cusp tips mesial