Development of the Primary and Permanent Dentition (Part II)

Question 1

Two characteristics of tooth eruption sequence of the permanent dentition

Answer 1

1. variability
2. sex differences

Question 2

What do we mean when we say the permanent dentition eruption is variable?

Answer 2

The eruption pattern sequence of the permanent dentition is more variable than that of deciduous dentition

Question 3

Describe the sex difference in regard to tooth eruption sequence of the permanent dentition:

Answer 3

Girls are ahead of boys in calcification, and except for the third molars, girls are ahead of boys by an average of 5 months in eruption

Question 4

T/F: Boys are ahead of girls in calcification

Answer 4

False- girls are ahead of boys

Question 5

T/F: Girls are ahead of boys by an average of 5 months in eruption excluding the 3rd molars

Answer 5

True

Question 6

What are the three rules of sequence timing of eruption?

Answer 6

1. timing is consistent within a dentition
2. both sides should erupt at the same time
3. different eruption sequences explain most frequently crowded teeth

Question 7

Explain the following statement:

“timing is consistent within a dentition”

Answer 7

children who erupt any tooth early or late tend to acquire others early or late

Question 8

T/F: Tooth eruption should occur bilaterally

Answer 8

true

Question 9

Different eruption sequences explain most frequently crowded teeth including:

Answer 9

1. maxillary cuspids
2. mandibular 2nd cuspids

Question 10

What is a local influence that accelerate permanent tooth eruption?

Answer 10

If the primary tooth is extracted DURING active eruption of permanent tooth (more than 2/3 of root is formed)

Question 11

What do we mean by active eruption of a permanent tooth?

Answer 11

more than 2/3 of root is formed

Question 12

What is a local influence that slows permanent eruption?

Answer 12

when a primary tooth is extracted BEFORE active eruption of permanent tooth (before root formation)

Question 13

What causes a change in arch width with the permanent dentition?

Answer 13

The increases are tied to alveolar process growth (both dental eruption and vertical process growth)

Question 14

What occurs during alveolar process growth?

Answer 14

1. dental eruption
2. vertical process growth

Question 15

Vertical alveolar process growth occurs during:

Answer 15

general growth spurts

Question 16

Compare the vertical alveolar process growth for the maxilla and mandible:

Answer 16

different rates

Question 17

Vertical alveolar process growth occurs at different rates for the maxilla and mandible: divergent maxillary process translates into:

Answer 17

more arch width growth

Question 18

What causes the rate of growth for the maxillary vertical alveolar process to be more drastic than the mandible.

Answer 18

divergent maxillary process

Question 19

What causes arch width changes? (3)

Answer 19

1. dental eruption
2. wider placement of permanent teeth
3. apposition of alveolar bone to support these teeth

Question 20

The maxillary arch-

1. increases occur during ____
2. Increases occur during ____
3. large increase occurs during ____

Answer 20

1. growth spurts
2. eruption of incisors
3. eruption of the cuspids

Question 21

What dilemma do we constantly face as dentists with tooth eruption?

Answer 21

moderate crowding

Question 22

Describe the “arch perimeter changes” with the maxillary arch: (3)

Answer 22

1. variable
2. no difference between sexes
3. factors which limit loss include greater labial angulation of incisors, greater increases in arch width and smaller leeway space

Question 23

In regard to arch perimeter changes with the maxillary arch, what factors limit loss?

Answer 23

1. greater labial angulation of incisors
2. greater increases in arch width
3. smaller leeway space

Question 24

Describe the curve of spee seen in the following image:

Answer 24

normal

Question 25

Describe the curve of spee seen in the following image:

Answer 25

steep

Question 26

What is a reasonable option for impacted third molars?

Answer 26

prophylactic extraction

Question 27

T/F: Extraction of third molars to avoid orthodontic relapse has a strong correlation

Answer 27

false- weak correlation