Prd 131: Molars,

Question 1

what are the functions of molars

Answer 1

• keep cheeks full (esthetic)
• chewing/grinding (mastication)
• vertical dimension of the face and occlusion. (vertical dimension of occlusion or VDO); height of lower 3rd face- proper distance chin and nose
• continuity of dental arch, keep other teeth in alignment

Question 2

when do the first molars erupt?

Answer 2

age 6

Question 3

what are the strongest/largest teeth in the arch

Answer 3

1st molars

-centered in arch, devestating for arch contunity to lose

Question 4

how much of their quadrant do the 3 maxillary/mandibular molars make up

Answer 4

maxillary : 44%

mandibular: 51%

Question 5

what can result in 6 or more molar loss

Answer 5

tmj problems

Question 6

GENERAL (all molars) ; what is wider, mesio distal or cervico occlusal

Answer 6

mesio distal is larger than cervico occlusal

Question 7

GENERAL : where are molars larger width wise, buccal or lingual? exception and why is it that way?

Answer 7

TAPER TO LINGUAL (larger buccal)

-EXCEPTION is first maxillary molar ; they have large disto-lingual cusps and may taper towards buccal.

Question 8

GENERAL: (all molars) which side is the taper, mesial or distal from occlusal view?

Answer 8

ALL taper distally!!! from occlusal view
-so its narrower buccolingually on distal than mesial and narrower mesiodistally on lingual than facial (general, except first maixlla)

Question 9

maxillary molars: what is wider, facio-lingual or mesio-distal?

Answer 9

facial lingual is greater!! BL>MD

more square/parallelogram than mandibular

Question 10

what shape occlusally is the mandibular first molar

Answer 10

pentagon shape! vs rectangle of other mandibular molarx

Question 11

what are the 4 cusps of maxillary 4 cusp molars? and the order of size

Answer 11

mesiolingual cusp > mesiobuccal cusp > distobuccal cusp > distolingual cusp

Question 12

what are the 4 cusps of maxillary 5 cusp molars and order of size (whats the 5th called and where is it?? which molar is it found in usually? how large is it?

Answer 12

mesiolingual cusp> mesiobuccal cusp>distobuccal cusp>distolingual cusp>cusp of CARABELLI

-cusp of carabelli is usually on the lingual of ML cusp of maxillary first molars on the side of occlusal table- SIZE VARIES

Question 13

for maxillary molars what are the ridges (cusps that form it) and what is the largest/longest cusp

Answer 13

mesial triangular ridge between ml and mb
distal triangular ridge : forms oblique ridge Mesiolingual to distal buccal !!!!

Question 14

which cusps form the oblique ridge on maxillary molars?

Answer 14

mesiolingual and distobuccal

Question 15

are all 5 maxillary cusps on occlusal table

Answer 15

5th cusp of carabelli is on side of occlusal table

Question 16

what is the size gradient of mandibular molar cusps

Answer 16

ML>DL>MB>DB

Question 17

where will you find a fifth cusp on mandibular molars/ which molars is it found on (how often?)

Answer 17

found on the first (USUALLY PRESENT) and SOMETIMES third molars!!!!!!!!!!!!!!!
-minor fifth cusp is called distal cusp and is next to distobuccal cusp

Question 18

GENERAL for molars: where is mesial/distal contact found? which is more cervical/ more occlusal? want to remmber

Answer 18

• mesial is at or near junction of the occlusal and middle thirds
• distal is in the middle third! (more cervical than the mesial)

Question 19

GENERAL for molars: where is the height of contor facial/lingual?

Answer 19

facial is in cervical third

lingual is in middle third!!!!!!1

Question 20

what is the arch trait rregarding tilt on mandibular molars?

Answer 20

mandibular molars tilt lingually relative to the root trunk!

note that all mandibular teeth tilt lingually when viewed from mesial or distal , but I think the tilt vs root is special

Question 21

what are the feature of maxillary molar roots? Name of each root, size vs crown and relative length of the roots?

Answer 21

contain mesiobuccal, distobuccal and lingual (or PALATAL) roots!!!!!!!!!!!

• roots are nearly twice as long as the crowns!
• relative length is palatal>mesiobuccal>distobuccal

Question 22

mandibular roots; which is longer than the other and what are the two

Answer 22

mesial and distal roots

mesial is usually slightly longer than the distal root

Question 23

how common is it to have wisdom teeth missing

Answer 23

20% of the population are missing one or more 3rd molar

Question 24

what is the last tooth to erupt

Answer 24

wisdom teeth

decay easily , may not contribute to function and may cause crowding

Question 25

type trait: comparing maxilary first and second molars' which is larger and where is it larger? which one tips and in which direction?

Answer 25

first molar is broader mesiodistally than the 2nd molar near the junction of the occlusal and middle third of the tooth!!!!!!!!!!! -2nd molar is often tipped distally on the root trunk! seee slide 29

Question 26

how many cusps are in the first and second maxillary molars? how often is it different?

Answer 26

four cusps in second molar, first molar has a fifth cusp 70% of the time!!!!!! otherwise four

Question 27

compare lingual cusps of first and second maxillary molars (both types of 2nd maxillary)

Answer 27

first: two well defined cusps ML and DL. fifth on mesiolingual cusp usualy (70%) carabelli. second (four cusp type): has ML and DL cusps second (three cusp type): Has DL cusp missing- only ML.

Question 28

what are the ridges and the cusps that connec tthem on first and second maxillary molars? how is oblique ridge different in 2nd vs 1st maxillary molars?

Answer 28

transverse ridge: ML to MB cusp oblique ridge: ML to DB cusp 2nd molars have a smaller oblique ridge than first molars do check slide 34 for in depth four cusp type

Question 29

FOUR CUSP TYPE of maxillary molar; which fossa does the central groove connect? where do the buccal groove, distal oblique groove, lingual groove, and transverse groove of oblique ridge descend from

Answer 29

- centrla groove connects the mesial fossa to the central fossa - buccal groove extends from the central fossa - distal oblique groove extends from the distal fossa (towards the lingual) - lingual groove extends from the distal oblique groove (continues it) onto the buccal wall - transverse groove of oblique ridge connects the central groove and the distal oblique groove

Question 30

what grooves are absent on the 3 cusp type of second maxilllary molar? what are the 2 major grooves of this molar?

Answer 30

two major grooves are buccal and central! -absent: distal oblique groove, lingual groove, and transverse groove of oblique ridge!

Question 31

what is at the buccal end of the distal oblique groove on four cusp type maxillary molars

Answer 31

distal triangular fossa

Question 32

what are the 4 fossae on four cusp maxillary molars?

Answer 32

mesial triangular fossa , central fossa, distal triangular fossa, and distal fossa (on the distal oblique groove)

Question 33

where does the buccal groove extend to on the buccal side of the second and first maxillary molars -which one more often has caries in the pit

Answer 33

extends into the middle third of the crown | -pit is SOMETIMES present at the end of the groove and can be a caries site but this is less often on the second molar

Question 34

maxillary first and second molars lingual groove- does it have a pit?

Answer 34

yes it has a pit at the end of the groove and can be a site for caries

Question 35

where are marginal ridge grooves usually found on maxillary 1st/second molars (mesial vs distal, first vs second molars?)

Answer 35

more common on mesial than distal, and more common on first than second molars

Question 36

what are tubercles? where are they often found and which maxillary molars?

Answer 36

projections of enamels- marginal ridges may have these. (bw marginal ridge grooves) -usually on mesial and rarely found on distal marginal ridge, RAREly on 2nd molars either!!!!!!!!!!!

Question 37

where is the furcation of the root for maxillary molars? (first and second)

Answer 37

junction of cervical and middle third of roots usually

Question 38

which has a longr root trunk-first or second maxillary molars?

Answer 38

second molars have a longer root trunk!

Question 39

in maxillary first molars; which roots bend and in what direction? how far does the MB root curve ?

Answer 39

mesiobuccal and distobuccal roots often bend (direction of db not sure) -mesiobuccal root may curve distally enough to put its apex distal to the buccal groove

Question 40

where is the root depression on maxillary molars? what is it continuous with

Answer 40

lingual aspect of the palatal root, may be continous with the lingual groove. -on first molars, the palatal root is the third longest of any maxillary tooth after canines and second premolars

Question 41

what are some features of maxillayr third molars (how many cusps, groove features and size?)

Answer 41

so much variation so its hard to describe - roots and crown are shorter than first or second molars - crown often has lots of supplemental grooves - may have 3, 4 or 5 cusps

Question 42

which tooth has the largest mesio-distal dimension of ANY tooth?

Answer 42

first mandibular molar!

Question 43

compare buccal cusps of first and second mandibular molars

Answer 43

first have 3 buccal cusps and second have 2!

Question 44

1st vs second mandib molar, which has a more prominent buccal heihgt of contour?

Answer 44

second molar is more prominent!!!!!!!! btw its in cervical third!

Question 45

how often is the 5th (distal) cusp of the first mandibular molar missing?

Answer 45

1/5th of the time. 15-20% have just four. so know that a 4 cusp is not ALWAYS a second molar!

Question 46

what is wider (Mesiodistally) the MB or the DB cusp on second mandibular molars?

Answer 46

MB is wider usually!

Question 47

what is longer, ML or DL on first and second mandibular molars?

Answer 47

ML is usually longer AND wider (slightly) than DL

Question 48

how many buccal grooves are on mandibular 1 and 2 molars

Answer 48

first has two, second has one

Question 49

what do the mesiobuccal and distobuccal grooves of first mandibular molar separate how do the grooves compare (pits, length)

Answer 49

mesiobucal; MB and DB cusps (may be a deep pit at cervical end of groove and can be a site for caries) distobuccal; DB and D cusp (shorter and not frequently pitted)

Question 50

how does the second mandibular molars buccal groove end

Answer 50

may end in the middle of the buccal surface in a PIT | so it could be carious

Question 51

how does the lingual groove of first and second mandibular molars end

Answer 51

in occlusal third with NO PIT | UNLIKELY to be carious

Question 52

what are the occlusal fossae of the mandibular molars (1 and 2)

Answer 52

THREE: mesial triangular fossa, central fossa, and distal triangular fossa -each or all may posess a pit.

Question 53

how do the triangular ridges of mandibular molars compare lingual vs buccal?

Answer 53

lingual cusps are taller so they have longer triangular ridges than buccal does.

Question 54

how does the cervical line slope on first and second mandibular molars? mesial,distal,buccal

Answer 54

- mesial CEJ of both first and second shapes OCCLUSAL from buccal to lingual! - distal cervical line is nearly straight, but slopes slightly occlusally!! - buccal cej is nearly straight across. occasionally a point of enamel slips down nearly into the root bifurcation is present!! can also have this on the lingual and it can cause periodontal issues

Question 55

how do first vs second mandib molar roots vary from each other in terms of divergence, proximity to the cej, root trunk? also where is there a depression on the root

Answer 55

first molars have bifurcation more cervical!! shorter root trunk than second molar. -first mandib molar roots diverge MORE than second!