Permanent Molars

Question 1

Describe the root trifurcation on maxillary permanent molars

Answer 1

Try furcation forms apical to the root trunk

2 buccal
1 palatal

Question 2

Which teeth are referred to as the cornerstones of the dental arches?

Answer 2

Maxillary and mandibular first molars

Question 3

Which maxillary teeth are the largest and strongest?

Answer 3

Maxillary first molars

Question 4

How many developmental lives to the maxillary first molars have?

Answer 4

4 lobes

Question 5

Where is the height of contour on the buckle and lingual aspects of the maxillary first molars?

Answer 5

Buccal cervical ridge end cervical third close to the CEJ

And on the lingual cervical third close to the junction of the cervical and middle third

Question 6

What is the cusp of Carabelli?

Answer 6

Supplemental fifth cusp on the maxillary first molars. Occasionally absent and varies in size and shape

Located on the mesial aspect on the ML cusp in the Occlusal third

Question 7

How much bigger or maxillary first molars than the maxillary pre-molars?

Answer 7

2 mm larger in all dimensions. Maxillary molars are wider buccolingually than mesiodistally

Question 8

What is the shape of a maxillary first molar?

Answer 8

Rhomboid

Mesial/distal surfaces are somewhat parallel but not at right angles

Question 9

What are the four Fosse of the maxillary first molars?

Answer 9

Central Fossa
Distal Fossa
Mesial triangular Fossa
Distal triangular fossa

Question 10

Where does the oblique ridge run from?

Answer 10

Runs obliquely from the triangular cusp ridge of the DB cusp to the distal cusp ridge of the mesial lingual cusp

Question 11

Where does the transverse Ridge run from?

Answer 11

Prominent ridge that course transversely from the triangular cusp ridge of the mesial buccal cusp to the triangular cusp ridge of the mesial lingual cusp

Question 12

How many ridges does each cusp have?

Answer 12

4 per cusp

Mesial, distal, buccal or lingual & occlusal/triangular cusp ridge

Question 13

What are the 3 pits on the maxillary 1st molars?

Answer 13

Central- very prominent
Distal- prominent
Mesial- not prominent

Question 14

Why is the route of the buccal groove?

Answer 14

From central pit over the buccal cusp ridge, nearly centered, onto the buccal surface and stops just above the buccal cervical ridge

Question 15

What is the route of the central groove of the maxillary 1st molar?

Answer 15

Courses across the central fossa in a mesial direction, ends in the mesial triangular fossa

Question 16

What is the route of the mesial marginal ridge groove in the maxillary 1st molar?

Answer 16

If present, extends from the mesial triangular fossa and crosses the mesial marginal ridge

Question 17

What is the route of the lingual groove on the maxillary 1st molars?

Answer 17

Extends from DOG to cross the LCR and travels down the lingual surface ending near the cervical line and may extend onto and down the palatal root

Question 18

What does the 5th cusp groove demarcate?

Answer 18

Cusp of Carabelli/5th cusp

Question 19

On which aspect may you find a depression on the mesial buccal root of the maxillary right first molar?

Answer 19

On the distal aspect

Question 20

Which is the smallest of root of the maxillary right first molar?

Answer 20

Distal buccal root

Question 21

Which is the largest and longest of all three roots of the maxillary right first molar?

Answer 21

Palatal root

Question 22

Describe the root trunk of the maxillary right first molar?

Answer 22

Short, try furcation occurs in the cervical third of the root

Question 23

How many pulp horns and canals are present in the maxillary right first molar?

Answer 23

4 pulp horns

3 to 4 pulp canals- usually 3 but if a 4th is present it will be in the MB root that may bifurcate

Question 24

What may occur if the apices of the maxillary first molars penetrate the floor of the maxillary sinus?

Answer 24

“Sinus infection” Made manifest as a toothache causing dental pain without the presence of dental disease

Question 25

What are enamel pearls?

Answer 25

Droplets of ectopic enamel occasionally found on the roots of teeth Uncommon, minor abnormalities which are formed on normal teeth

Question 26

What is root fusion?

Answer 26

When two tooth buds fuse to make a large tooth

Question 27

What is germination?

Answer 27

Caused by a single tooth germ that attempted to divide during its development, resulting in a bifid crown

Question 28

What is the difference in Crown size between the three molars?

Answer 28

Second and third molars are progressively smaller than first molars. B/L width is about the same, M/D width about 1mm smaller Crown is shorter. Buccal cusps about same size, lingual cusps are smaller

Question 29

Describe the shape of the occlusal aspect of the maxillary right second molar

Answer 29

Rhomboid or heart shaped

Question 30

Describe the occlusal anatomy of the maxillary second molars

Answer 30

The same but not as distinct or prominent as the first molars

Question 31

Describe the buccal groove of the maxillary second molars

Answer 31

Does not cross the buccal height of contour

Question 32

Describe the lingual groove of the maxillary second molars

Answer 32

Does not extend past the lingual height of contour

Question 33

Describe the roots of the maxillary second molar in comparison to the maxillary first molar

Answer 33

All three roots are contained within the crown outline. Not as divergent and are the same length

Question 34

Where does the trifurcation occur on the root trunk of the maxillary second molar?

Answer 34

The middle third of the root trunk

Question 35

Describe the crowns of the maxillary third molars

Answer 35

Smallest of the maxillary molars. Distal lingual cusp is very small and may not be present

Question 36

Describe the shape and anatomy of the occlusal all aspect of the maxillary third molar

Answer 36

Usually heart shaped due to reduction or loss of the distal lingual cusp Very irregular with less prominent grooves and pits

Question 37

Describe the roots of the maxillary third molars

Answer 37

Shortest roots of all three maxillary molars. Vary greatly and often all are fused together. If fused then grooves will be present to demarcate the roots. Can also be spreader wide apart

Question 38

Describe the size of the crowns on the mandibular molars

Answer 38

Wider mesial/distal than buccal/lingual Opposite of the maxillary molars

Question 39

Describe the roots of the mandibular Molars

Answer 39

Bifurcated: one mesial and one distal. Third molars and some second molars have fusion of these roots

Question 40

Difference between the roots of the mandibular molars to other mandibular teeth

Answer 40

Molar roots may be a little shorter but multiple roots and broad trunks give them superior anchorage

Question 41

What is the largest mandibular to end the corner stone of the dental arches?

Answer 41

Mandibular ( and maxillary) first molars

Question 42

How many lobes form the mandibular first molar?

Answer 42

Five developmental lobes

Question 43

How many cups on the mandibular first molars?

Answer 43

5 cusps Two buccal (MB, DB), one distal, two lingual (ML, DL) Some may only have four cusps, lacking a distal cusp or the distobuccal and distal cusps are fused

Question 44

Describe the cusp tips and cusp bridges of the mandibular first molars

Answer 44

Cusp tips are somewhat flat Cusp ridges are less convex each cusp has four

Question 45

Describe the MB groove of the Mandibular first molar

Answer 45

Longer, in middle third, just mesial to buy furcation May terminate in a pit

Question 46

Describe the DV groove of the mandibular first molar

Answer 46

Shorter, found just mesial to the DB line angle Often no pit present

Question 47

Do the mandibular first molars have a lingual depression?

Answer 47

There will be a lingual depression if a lingual groove is absent Lingual groove separates the lingual cusps and extends onto the lingual surface

Question 48

Which root is wider and longer on the mandibular first molars

Answer 48

Mesial root

Question 49

What is the shape of the occlusal table on the mandibular first molars?

Answer 49

Y or + shaped

Question 50

Form and position of the roots on the mandibular first molars

Answer 50

Roots brace the crown against the occlusal forces and prevents the tooth from rotating

Question 51

How many pulp horns and pulp canals in the mandibular first molars?

Answer 51

Five pulp horns Three pulp canals or two if the mesial root has only one canal Distal root only has one canal

Question 52

What happens when the mandibular first molars are missing?

Answer 52

Teeth become inclined and there is a mesial drift of the mandibular second molar and possibly third molar. Super eruption of the maxillary first molar into the opposing open space

Question 53

What is a fault pit?

Answer 53

Mandibular buccal pit. Created due to the tiny localized imperfect fusion or defective formation of enamel, found at the buccal and lingual terminations of developmental groups

Question 54

How do the mandibular second molars compare in size to the first molars?

Answer 54

Mandibular second molars are smaller than mandibular first

Question 55

How many cups do mandibular second molars have?

Answer 55

For costs. Usually no distal cusp or fifth cusp

Question 56

How do the roots of the mandibular second molars compare to the roots of the mandibular first molars?

Answer 56

Root trunk is longer and they tend to tilt distally. Mesial route is not as broad and roots are not divergent. May be fused partially or completely

Question 57

How do the mandibular third molars compare to the mandibular first and second molars?

Answer 57

Very considerably and have many anomalies in form and position Tends to be more like a second molar than a first molar. Enamel is usually thicker and crown is often oversized with short, poorly formed roots Contributes to periodontal defects on distal of mandibular second Often congenitally missing, usually bilaterally