Dental Anatomy Unit 5 Quiz

Front 1

length of maxillary premolars

Back 1

the first is generally longer than the second one. while in the mandibular premolar the first is considerably smaller.

Front 2

thickness of premolars

Back 2

the crowns of max. premolars are normally wider bucolingually than mesiodistally, but they are nearly equal in the mandibulars.

Front 3

number of root branches of maxillary pre molars normally seen

Back 3

two

Front 4

dev. table of max. first premolar

Back 4

ioc - 1.5-1.75 years

- completion of enamel - 5-6 years

- eruption - 10-11 years

- completion of root - 12-13 years.

Front 5

max. 1st premolar ; buccal aspect

Back 5

- larger than second premolar; canine cusp tip is a little bigger and

- occlusocervical dimension is less than any ant. tooth but larger than any of the other post. teeth.

Front 6

1st premolar ; buccal aspect ; mesial margin

Back 6

- shallowly concave from the CA to the cervcal line.

Front 7

1st premolar; buccal aspect; distal margin

Back 7

slightly shorter than mesial edge

- disto occlusal angle is a little less prominent and the cervical concavity is not as deep.

Front 8

1st premolar; buccal aspect; occlusal outline

Back 8

- facial cusp tip is pronounced

- divided into two unequal portions
- mesioocclusal slope - longer and straighter

- disto occlusal - shorter and more curved

- this means the cusp tip is slightly offset to the distal.

Front 9

1st premolar; buccal aspect; other considerations

Back 9

-buccal ridge - extends about halfway along the surface from the tip of the buccal cusp toward the cervical line. results from the greater dev. of the middle buccal lobe.

-mesiobuccal and distobuccal developmental depressions - present on each side of the buccal ridge and appear to divide the occlusal portion of the buccal surface into vertical thirds.

Front 10

1st premolar ; lingual aspect ; general considerations

Back 10

- smoothly convex in all directions

- crown tapers toward the lingual, so crown is narrower mesiodistally at the crown than at the lingual.

- lingual cusp tip is NOTICABLY offset to the mesial.

- can see both cusp tips from the lingual aspect because the lingual crown is narrower than the buccal.

Front 11

1st premolar; lingual aspect; mesial and distal outlines

Back 11

somewhat convex and shorter than the same outlines of the buccal surface.

Front 12

1st premolar; lingual aspect; occlusal outline

Back 12

- lingual tip isn't as sharp as buccal cusp tip.

- offset towards the mesial

- shorter than the buccal cusp by as much as 1 mm.

Front 13

1st premolar ; lingual aspect ; other considerations

Back 13

no dev. depressions, grooves or pits are normally found on this surface.

Front 14

1st premolar; mesial aspect; occlusal margin

Back 14

- irregularly concave and made up of the mesial marginal ridge.

- indents the occlusal margin almost 2/3 of the way from the buccal to the lingual outline.

Front 15

1st premolar; mesial aspect;cervical margin and other considerations

Back 15

cervical
- irregularly convex towards the occlusal
- equal to the distal cervical line of the k9

Other considerations
- mesial concavity - unique feature of the max. fist premolar. variable in extent.
- usually in the middle portion of the cervical 1/3.

CA is circular in shape and near the jnxn. of the middle and occlusal 1/3

Front 16

1st premolar; distal aspect; general considerations; buccal margin; lingual margin; occlusal margin

Back 16

general - similar to mesial but only slightly longer.

buccal margins - convex with COC in gingival 1/3

lingual margin - almost symettrical and is quite convex. HOC in middle 1/3

occlusal margin - similar to mesial but the marginal ridge is located at a more cervical level.
- so you can see more of the occlusal surface here.

Front 17

1st premolar; distal aspect; cervical margin and other considerations

Back 17

cervical margin
- less than the mesial

other considerations
- distal contact area is larger than the mesial and is located more cervical. OVOID outline
- wider buccolingually than occlusogingivally.

- distal surface is generally convex in all directions and DOES NOT exhibit the concavity like the mesial surface.

Front 18

1st premolar; occlusal aspect; general considerations

Back 18

outline is hexagonal and wider buccolingually than mesiodistally.

Front 19

components of the occlusal cusp

Back 19

buccal cusp and the lingual cusp

Front 20

buccal cusp

Back 20

buccal cusp tip is located well toward the buccal, and is offset to the distal.

- wider and higher than the lingual cusp.

- has 4 cusp ridges

Front 21

4 cusp ridges of the buccal cusp

Back 21

buccal, lingual, mesial and distal.

Front 22

buccal cusp ridge

Back 22

extends cervically fromthe cusp tip on the buccal surface

Front 23

lingual cusp ridge

Back 23

extends lingually from the cusp tip to the central groove.

- one of two triangular ridges found on the tooth.

- the lingual cusp ridge of the buccal cusp is synonymous with the buccal triangular ridge of the tooth.

aka. - the buccal portion of the transverse ridge.

Front 24

mesial cusp ridge

Back 24

extends mesially from the cusp tip to the mesiobucco- occlusal point angle.

Front 25

distal cusp ridge

Back 25

extends from the cusp tip to the distobuccal- occlusal point angle area.

Front 26

four inclined planes of buccal cusp

Back 26

mesiobuccal inclined plane (non functional)

distobuccal inclined plane (non funct.)

mesiolingual inclined plane (functional)

distolingual inclined plane (functional)

Front 27

during active occlusion

Back 27

the buccal cusps of the max. post. teeth are functional only on their lingual sides, so the only functional incline planes are on the lingual surface.

Front 28

lingual cusp

Back 28

offset toward the mesial.

- shortest of all the max. premolar cusps.

- four cusp ridges and planes that are named the same as the buccal.

Front 29

components of the occlusal cusp table; transverse ridge

Back 29

the buccal and lingual triangular ridges ofthe tooth meet int he area of the central groove, forming a transverse ridge.

Front 30

components of the occlusal cusp table; marginal ridges

Back 30

form the mesial and distal border of the occlusal surface.

- run from bucco to medio occlusal point angles.

- named mesial and distal marginal ridges.

mesial marginal ridge is normally shorter and its continuity is interrupted by the mesial marginal groove.

Front 31

mesial marginal groove

Back 31

interupts the mesial marginal ridge about near its midpoint.

Front 32

components of the occlusal cusp table; fossae

Back 32

mesial triangular fossae - roughly triangular in shape and bounded by

- mesial marginal ridge
- transverse ridge
- and the mesial cusp ridge

distal triangular fossae

- has a shape and boundaries similar to mesial triangular fossae but not quite as deep.

Front 33

components of the occlusal cusp table; pits and grooves

Back 33

two pits
- mesial pit - in the mesial triangular fossae
- point of meeting for four primary or developmental grooves.

- distal pit - located just inside the distal marginal ridge, midway buccolingually and is the point of union of 3 primary grooves.

Front 34

Grooves of the occlusal cusp table

Back 34

1. mesiolingual triangular groove - extends from the mesial pit in a mesiolingual direction.

2. mesiobuccal triangular groove - similar to ML groove but runs in a buccal direction.

3. central groove - the central groove has a mesiodistal direction and connects the mesial and distal pit.

4 mesial marginal groove - extends from the mesial pit in a mesial direction crossing over the mesial marginal ridge and running up the mesial border of the tooth for a short distance.

Front 35

number of secondary grooves on the max. 1st versus the second premolar

Back 35

the 1st usually has less secondary grooves then the second

Front 36

1st premolar; Root

Back 36

usually two branches (unique since most other premolars have only one)

Front 37

1st premolar; different root types

Back 37

1. single root

2. bifurcated root

3. laminated root

Front 38

1st premolar ; root; single root

Back 38

- straight and tapers evenly
- wider buccolingually than mesiodistally

- buccal portion of root is a little larger than the lingual

- usually has a longitudinal groove continuous with the mesial concavity.

- distal longitudinal groove normally exists as well (not as pronounced)

- midroot cross section - looks like a kidney
- buccal and lingual edges are convex with the mesial being concave and distal being straight or slightly concave.

Front 39

1st premolar ; roots; bifurcated root

Back 39

- buccal and lingual branches
- root trunk - the protion of the root situated between the cervical line and the point of furcation (branching)

- usually bifurcated for half the length of the tooth.

- all surfaces of the root branches are convex

- buccal root branch is larger in size. but they are about equal in length.

Front 40

1st premolar; roots; laminated root

Back 40

similar to type 2 but the buccal and lingual branches are attached by a lamination (thin connection)

- midroot cross section - hour glass figure.
- similar to class 1 but the distal edge is more concave like the mesial edge.

Front 41

1st premolar; variations and anomalies

Back 41

the roots may penetrate the ant. portion of the maxillary sinus (antrum)

Front 42

2nd premolar differences from the 1st premolar

Back 42

- crown is smaller in all dimensions
- generally less blocky (more rounded crown)
- buccal and lingual cusps are nearly equal in height
- normally NO mesial concavity or marginal groove found on the crown of the second premolar.

- second premolar is normally a single rooted tooth.

- more variations from normal.

Front 43

2nd premolar; dev. table

Back 43

ioc - 2-2.25 years

COE - 6-7

eruption - 11-12

COR - 12-14

Front 44

2nd premolar ; buccal aspect

Back 44

similar to max. with following exceptions

1. buccal cusp is not as long or pointed

2. cusp tip is offset to mesial, so the mesioocclusal slope is slightly shorter than the distolingual

3. mesio occlusal and distoocclusal line angles are not as prominent, and the miesial outline is not quite so concave.

Front 45

2nd premolar; lingual aspect

Back 45

similar to max. with these exceptions

1. the lingual cusp is relatively longer, making the crown longer on this side.

2. lingual cusp tip is not so far offset mesially.

Front 46

2nd premolar; mesial aspect

Back 46

similar to max. with these exceptions

1. two cusps are nearly the same length

2. no mesial concavity, and instead this part is slightly convex or straight.

3. mesial marginal groove is usually absent

4. both the marginal ridge and CA are at a slightly more cervical level than on the mesial of the 1st premolar.

Front 47

2nd premolar; distal aspect

Back 47

similar with the following exceptions

1. 2 cusps are about the same length.

2. the CA is LARGER in size, since the 2nd premolar CA on the distal side is with the 1st molar.

3. both the distal CA and marginal ridge are found at a slightly more cervical level than on the 1st

Front 48

2nd premolar ; occlusal aspect

Back 48

differs from maxillary in these ways

1. line angles of the crown are more rounded, so the crown appears less angular

Front 49

2nd premolar; occlusal aspect

Back 49

2. central groove is shorter; more secondary grooves and the mesial and distal pits are closer because of the shorter central groove.

3. mesial marginal groove is normally absent

4. the lingual cusp tip is normally not quite as far offset to the mesial.

5. on the lingual cusp there are four functional inclined planes, whereas the first exhibited only 3

Front 50

2nd premolar ; root

Back 50

1. single and tapers and tapers to a blunt apex.

2. root length is normally as great or greater than the 1st premolar.

3. root is wider buccolingually than mesiodistally

- mesial and distal edges are normally flat or slightly convex.

- in cross section the outline is normally ovoid.

- may be offset to the distal in its apical part.

Front 51

2nd premolar; variations and anomalies

Back 51

1. central groove may be absent so only a central pit is located on the occlusal surface.

2. root variations occur - apical portion could have a distal offset or there may be two roots.

3. the root may penetrate the antrum.