Deciduous Teeth

Question 1

Which primary molars could be mistaken from permanent molars?

Answer 1

Primary maxillary and mandibular 2nd molars

Question 2

Which primary molar could be mistaken for a premolar?

Answer 2

Maxillary 1st molar

Question 3

Which primary molar looks like no other tooth, either deciduous or permanent?

Answer 3

Mandibular 1st molar

Question 4

How are the primary molar roots different from a permanent molar?
a. How are they similar?

Answer 4

Flared much more

a. Same number of roots

Question 5

From a proximal view, how does the angulation of the primary anterior root differ from the permanent anteriors?

Answer 5

Flared facially (labially)

Question 6

How many Mamelons does a primary anterior incisor have?

Answer 6

None

Question 7

Which primary anterior tooth is most likely to exhibit a lingual pit?

Answer 7

Maxillary central

Question 8

How does the crown:root of a primary tooth compare with a permanent’s?

Answer 8

Primary crown smaller and root longer (in comparison)

Question 9

In a normal 10-year old child, how many primary and permanent teeth would you expect to find?

Answer 9

Primary 10, Permanent 14

Question 10

How do the primary maxillary central and lateral incisors compare with the permanent incisors?

Answer 10

Flatter, more round, plump

Question 11

What is unique about the relative lengths of the MD to IC dimensions of the primary maxillary central incisor?

Answer 11

MD > IC

Question 12

What incisal feature is missing from primary incisors but is seen unworn incisal edges of permanent incisors?

Answer 12

Mamelons

Question 13

A unique feature of the primary maxillary canine is the relative lengths of the mesial and distal cusp ridges. Which is longer, which is shorter?
a. How is this unique?

Answer 13

Mesial cusp ridge > distal cusp ridge

a. Mesial is longer than distal to start

Question 14

A unique feature of the primary maxillary and mandibular canines is the location of their mesial and distal HOC’s. What is unique about their relative position?

Answer 14

They are equal

a. Mesial might be more cervical

Question 15

Which two cusps are prominent and which two are diminished in a primary maxillary 1st molar?
a. Which of the four cusps might not be evident at all?

Answer 15

ML (Largest) MB (next largest)

a. DL

Question 16

What is unique about the curvature of the facial cervical line of a primary maxillary 1st molar?

Answer 16

Depth of curvature towards mesial

Question 17

From an occlusal view of the primary maxillary 1st molar, it presents a figure that has how many sides?
a. Which permanent teeth would this most closely resemble?

Answer 17

5 sided

a. 3 cusp premolar

Question 18

How does the relative size of a primary maxillary 1st and 2nd molar compare with each other?
a. How is this different from that of a permanent maxillary 1st and 2nd molar?

Answer 18

2nd larger than the first

a. Opposite (1st is larger than the 2nd)

Question 19

Which permanent or primary tooth does the primary mandibular 1st molar resemble?
a. What are the features that identify it as a mandibular molar?

Answer 19

None

a. 4 cusps, 2 roots

Question 20

There is a definitive offset of the facial cervical line of a primary mandibular 1st molar. Where is this offset located?

Answer 20

Mesial

Question 21

How is the number of cusps of a primary mandibular 1st molar differ from that of a permanent mandibular 1st molar?

Answer 21

4 cusps on primary (5 cusps of permanent)

Question 22

Which occlusal pit is most often missing in a primary mandibular 1st molar?

Answer 22

Distal pit

Question 23

Which tooth does the primary mandibular 2nd molar most closely resemble?

Answer 23

Permanent 1st mandibular molar

Question 24

What is dental lamina derived from?

Answer 24

Oral Epithelium

Question 25

What happens during the bud stage of formation?

Answer 25

Epithelial thickening (dental lamina) – 6-8 weeks fetal development

a. Differentiated into tooth buds
b. Buds: round or ovoid

Question 26

What appearance occurs during the cap stage?

Answer 26

Cap Stage

a. Enamel organ →ameloblast
b. Dental papillae → odontoblast
c. Dental follicle → cementoblast, osteoblast, fibroblast

Question 27

What happens during the bell stage of development?

Answer 27

Concavity deepens

a. DEJ identifiable
b. Permanent tooth bud begins formation

Question 28

What begins the formation of the root development?

Answer 28

Hertwig’s Root Sheath

a. Bell stage = formation of CE Line

Question 29

What happens at root completion?

Answer 29

One year from eruption to completion

a. Apical foramen become constricted

Question 30

What are the two types of Eruption?

Answer 30

Eruption

a. Active → entry of tooth till it touches other teeth
b. Passive → continuous adaptation (throughout life)

Question 31

Pattern of Deciduous Eruption Pattern?

Answer 31

Central Incisors → Lateral incisors → First Molar → Canines → Second Molar
a. Mandibular before maxillary

Question 32

What is the Mixed Dentition Period?

Answer 32

6-12 years (form “primate” spaces)

Question 33

Where do the permanent teeth develop in relations to primary teeth?

Answer 33

Development

a. Anteriors → permanent are lingual to primary
b. Premolars → within the flared roots

Question 34

Resorption is what kind of a process?

Answer 34

Osteoclastic Processes

a. One year prior to exfoliation

Question 35

What is Ankylosis?

Answer 35

Root fused to bone, disrupts resorption and exfoliation

Question 36

What is the Dental formula for primary dentition?

Answer 36

I 2/2 C 1/1 M 2/2

a. Important to maintain arch spacing for permanent dentition