Mixed Dentition- Dr. Retrouvey (FINAL)

Question 1

The difference is sizes of the primary anterior incisors & the permanent anterior incisors:

Answer 1

Incisor liability

Question 2

Lower permanent incisors erupt _____ to the primary

How does this affect the arch size?

Answer 2

Lingually; Arch size decreases

Question 3

Upper permanent incisors erupt ____ to the primary

How does affect the arch size?

Answer 3

Labially/facially; Arch size increases

Question 4

Dental arch measurements include (4):

Answer 4

1. Arch length
2. Arch width
3. Arch perimeter
4. Intercanine distance

Question 5

Measured at the midline to a tangent touching the distal surfaces of the secondary primary molar

Answer 5

Arch length

Question 6

Arch length (depth) is measured at the midline to a tangent, touching the ____ surfaces of the _____

Answer 6

Distal surfaces; second primary molars

Question 7

The arch length is stable one the:

Answer 7

Permanent incisors are in

Question 8

If one sees “growth” of the arch length after the primary incisors are in, this is due to _____ not actually due to ____

Answer 8

DISPACEMENT; NOT growth

Question 9

Arch length changes include:

Answer 9

1. Lose arch length in lower arch (due to lower incisor eruption)
2. Gain arch length in the upper arch (due to upper incisor eruption)

Question 10

Measured between the cusps of the canine tips in the transverse plane:

Answer 10

Arch width

Question 11

Measured between the occlusal grooves of the second primary molars:

Answer 11

Arch width

Question 12

Arch widths are given in ____ measurements

Answer 12

Two different which allows you to estimates of the transverse development of the arches

Question 13

Although “there are no significant changes from primary to mixed dentition in the lower arch width”

there is about 4mm of changes between ages:

Answer 13

4-12 years

Question 14

Intercanine distance increases until age ____ in girls & ____ in boys

Answer 14

10-11 years girls
11-12 years boys

(+3-4 mm

Question 15

Measured from the distal surface of the second primary molar around the arch, over the contact points & incisal edges in a smoothed curve:

Answer 15

Arch perimeter

Question 16

Arch perimeter before treatment is referred to as the:

Answer 16

Baseline

Question 17

The elongation of the roots has nothing to do with:

Answer 17

Tooth eruption

(rather the crown is pulling the root)

Question 18

From ____ to ___ years old, the primary dentition is replaced by the permanent dentition resulting in mixed dentition

Answer 18

6 to 13

Question 19

The permanent first molars erupt to the ____ of the primary dentition (no primary tooth replacement)

Answer 19

distal

Question 20

First, second & third molars do not:

Answer 20

Replace primary dentition

(they erupt distal to primary dentition)

Question 21

Primary root resorption is a result of:

Answer 21

Permanent tooth eruption

Question 22

Permanent tooth eruption causes:

Answer 22

Primary root resorption

Question 23

Put the following events in order:

(a) Primary tooth starts to resorb

(b) permanent root develops

(c) crown of permanent tooth is formed

Answer 23

1. Crown of permanent tooth is formed
2. permanent root develops
3. Crown of permanent tooth is formed

Question 24

When does the primary tooth exfoliate & permanent tooth erupt?

Answer 24

When the primary root is totally resorbed

Question 25

What happens when the primary root is totally resorbed?

Answer 25

The primary tooth exfoliates & the permanent tooth erupts

Question 26

When does the permanent tooth stop erupting?

Answer 26

when it reaches the occlusal plane or contacts an opposing tooth

Question 27

What gives the power to cause the primary root to resorb/baby tooth to exfoliate?

Answer 27

Permanent tooth eruption

Question 28

Permanent tooth

Question 29

What do we mean “root development is NOT a main factor in eruption”

Answer 29

The root forms at the same time that the tooth erupts (IT DOES NOT PUSH THE CROWN UP)

Question 30

You should not do a panoramic X-ray before the age of:

Answer 30

8

(too complex to distinguish with mixed dentition)

Question 31

For eruption of permanent dentition, there are variable patterns between:

Answer 31

3-4-5

(canine, 1st P, 2nd P) <— ?

Question 32

Tooth replacement sequence is variable in terms of: (5)

Answer 32

1. Sequence
2. Timing
3. Position
4. Numbers
5. Shape

Question 33

What are the tooth eruption patterns for teeth 3, 4, 5:

Answer 33

-3,4,5
-4,3,5
-4,5,3

(Note: it doesn’t start with 5)

Question 34

At the age of 13 years, describe what the dentition should look like:

Answer 34

most permanent teeth should be in

Question 35

The root of the permanent tooth has to be _____ formed PRIOR to extraction of primary tooth

Answer 35

2/3 formed

Question 36

Variability in tooth number can be a result of:

Answer 36

ethnicity

Question 37

Congenitally missing teeth are rare, effecting _____ % of the population

Answer 37

3-5

Question 38

What is the most frequently congenital tooth in Caucasian population?

Answer 38

Maxillary lateral incisor

Question 39

What are two common congenitally missing teeth?

Answer 39

1. maxillary lateral incisor (most frequent)
2. mandibular second premolar

Question 40

A missing primary tooth= _____ meaning ____

Answer 40

no permanent successor= delayed eruption

Question 41

Affects the growth of the alveolar processes:

Answer 41

Ankylosis

Question 42

Refers to the fusion of part of the root of the primary tooth to the underlying bone which stops the tooth from erupting:

Answer 42

Ankylosis

Question 43

Ankylosis may be due to localized defective during eruption process, in the _____ whereby _____

Answer 43

PDL; Osseous

Question 44

Ankylosis becomes more prevalent in mixed dentition where occlusal level of ankylosed tooth:

Answer 44

Does NOT keep up with vertical level of the adjacent teeth

Question 45

What is responsible for keeping the teeth in contact during growth & may play a role in ankylosis:

Answer 45

Dentoalveolar development

Question 46

Treatment of ankylosis usually invovles:

Answer 46

Simply monitor these teeth (50% self correction)

Question 47

If an ankylosed tooth fails to correct itself/fails to exfoliate, it may be advisable to:

Answer 47

Extract the tooth to avoid damages to the permanent dentition

Question 48

When the tooth is growing in the complete wrong position

Answer 48

Ectopic eruption

Question 49

The most common tooth displaying an ectopic eruption is the:

Answer 49

mandibular canine