Development and Anatomy of Primary Dentition (Lecture 5) Flashcards Preview

Dental Development and Anatomy > Development and Anatomy of Primary Dentition (Lecture 5) > Flashcards

Flashcards in Development and Anatomy of Primary Dentition (Lecture 5) Deck (67)
Loading flashcards...
1

What is the primary dentition?
§ Dentition before the eruption of _____ 
§ What else are the primary teeth called?
§ _____ (comes from a Latin word “deciduus” which means fall off) teeth
§ Baby teeth
§ _____ teeth

§ When do primary teeth emerge in the mouth?
§ Between the ages of _____

permanent teeth
deciduous
milk
6 months and 2 years

2

Humans are _______

diphyodont, have two sets of teeth

3

Although replaced by the succedaneous teeth, primary teeth play a very important role for the proper _______ and _______ of the permanent teeth

position
occlusion

4

How many are the primary teeth?
§ Twenty (20)
§10 maxillary and 10mandibular teeth
§ In each arch:
§ _______ incisors
§ _______ cuspids (canines)
§ _______ molars

4
2
4

5

Primary Dentition

§ No _______
§ Primary molars are replaced by _______
§ Permanent molars have no _______ and erupt _______ to primary molars

primary premolars
premolars
predecessors
distal

6

Palmer vs. Federation Dentaire International Numbering System

L shaped dictates location for palmer
quadrants dictate dentaire (1-4 for permanent, 5-7 for primary, then 51 etc.)

7

When does the development of primary teeth start?
_______ weeks in ____

When does calcification of the primary teeth start?
____ in utero

How much of the crown of primary teeth has formed at birth?
____ (approximately)

By when the enamel formation has been completed for all primary teeth?
By ____ of age

6-8 weeks, utero
14-20th week
1/2-5/6
12 months

8

Stages of development (eruption) of the dentition
Birth - 6 months: ___
6 months - 2.5 years: ___
2.5 years - 6 years: ____
6 - 12 years: _____
> 12 years: _____

edentulous arches
eruption of primary teeth
full primary dentition
mixed dentition
permanent dentition

9

Birth -6 months of age
___ usually visible at birth
What is an exception?
___ or ___ teeth

no teeth
natal -> present at birth
neonatal -> erupt 30 days of birth

10

Natal and Neonatal Teeth
q Natal teeth
q ___ at birth
q Neonatal teeth
q Erupt within ___ after birth
q May be ___ teeth
q More likely early eruption of ___
q Unknown why they occur; superficial position of the tooth germ, associated with a ___

present
30days
extra
primary teeth (85%)
hereditary factor

11

When does the eruption of the primary teeth start? Which is the first primary teeth to erupt?Does eruption of primary teeth happen earlier in boys or girls?

§ ___ of age -> First primary tooth erupts
§ ___
§ Boys and girls have similar eruption times for ___ (in contrast to ___ teeth: girls do erupt their permanent teeth ___ than boys)

6-10 months
mandibular central incisor
primary
permanent
earlier

12

Calcification of roots normally is completed by age ___- Active eruption occurs when ___ of the root is formed - Usually erupt in ___

3-4 years
2/3
erupts

13

7+4
Explain

7 months is starting point
11 months = 4 erupted teeth
15 months = 8 erupted
19 months = 12 erupted
23 months = 16 erupted
27 months = 20 erupted

14

Sequence of Eruption of Primary Teeth
___ before maxillary
§ ___ to back except ___ before canine

mandibular
front
1st primary molar

15

3 years
§ Primary teeth in ___

occlusion

16

3 1⁄2 years
§ All primary teeth in ___ and ___ completed

occlusion
roots

17

Spacing in primary dentition
§ ___ spacing
§ interdental spacing mostly in the ___ area of the mouth

§ Primate spacing
§ Distal to the ___
§ Distal to upper ___
§ ___ (than the rest of interdental) spaces

generalized
anterior

lower primary canine
primary lateral incisor
wider

18

Primate Spaces
• Naturally occurring spaces in the primary dentition
• Maxillary: between the ___ and ___
• Mandibular: between the ___ and ___

lateral
canine
canine
molar

19

§ SPACED
§ ___ of primary dentitions: spaced
§ ___ of primary dentition: non spaced
§ Once established, arches ___ spaced or non- spaced over the course of primary dentition

2/3
1/3
remain

20

Does primary spacing affects crowding outcome into the permanent dentition?
Spacing >= 6mm = ___
Spacing 3-6 mm = ___
Spacing < 3 mm = ___
No spacing = ___
Crowded primary = ___

no crowding
20% crowding
50% crowding
66% crowding
100% with incisor crowding

21

Molar relationship
§ Defined by the mesiodistal relation between the ___ surfaces of the upper and lower ___ (terminal plane)
§ 3 types
§ ___ terminal plane
§ ___ step terminal plane
§ ___ step terminal plane

distal
second primary molars
flush
mesial
distal

22

Flush terminal plane
§ The upper and lower distal surface of the second primary molars are in the ___ plane

same vertical

23

Mesial step terminal place
§ Distal surface of the lower second primary molar is more ___ to the ___ surface of the upper second primary molar
Step is defined by ___

mesial
distal
mandibular primary molar

24

Distal step terminal plane
§ Distal surface of the lower second primary molar is more ___ to the ___ surface of the upper second primary molar

distal
distal

25

Canine (cuspid) Relationship
§ Mesial stepà___
§ Distal stepà___
§ Excessive mesial stepà___

§ Class I: the tip of the max primary canine is in the ___ as the distal surface of the mandibular primary canine
§ Class II: the tip of the max. primary canine is ___ to distal surface of the mandibular primary canine
§ Class III: the tip of the max. primary canine is ___ to the distal surface of the mandidbular primary canine

class I
class II
class III
same plane
mesial
distal

26

Overjet and Overbite
§ Ideal
§ Overjet: ___
§ Overbite: ___
§ ___ in primary dentition
§ may indicate ___
§ ___ or open bite
§ may be evidence for a habit i.e., ___

0-4mm
10-40%
excessive overbite
skeletal malocclusion
excessive overjet
thumbsucking

27

Can we predict the size of the permanent dentition from the size of the primary teeth?
§ Correlation coefficient (r) values between size of the primary and permanent teeth range from r= ___
§ There is little if any about primary dentition size that predicts ___
§ Correlation coefficients of r= ___ or higherare required to make predictions for theindividual patient at chairside

0.2-0.6
permanent dentition size
0.8

28

Primary Dentition vs. Perm Dentition

Crowns of ___ teeth
u ___ width is close to, or greater than, the ___ length dimension
n Roots of primary anterior teeth are ___ and ___ in relation to their crowns

primary anterior
mesiodistal (MD)
incisalgingival (IG)
narrower
longer

29

§ Roots of primary molars are relatively ___, more ___ and flare ___ than the permanent counter parts
§ Why are the roots of the primary molars more flare than those of the permanent teeth?

longer
slender
more
make room for the growing permanent tooth bud

30

Cervical ridges (___) of the primary anterior teeth and posterior teeth are more ___ than those of the permanent

buccally
prominent