permanent dentition

Question 1

variabilty in eruption sequence

Answer 1

More so than deciduous dentition, the

sequence is VARIABLE

Question 2

gender differences in eruption sequence

Answer 2

Girls are ahead of boys in calcification and
except for the third molars, girls are ahead of boys
by an average of 5-6 months in the eruption
pattern

Question 3

lower arch sequence of eruption

Answer 3

Question 4

lower arch eruption times

Answer 4

Question 5

maxillary eruption sequence

Answer 5

Question 6

why would you extract the primary canine

Answer 6

to redirect secondary eruption path

Question 7

maxillary eruption times

Answer 7

Question 8

timing of eruption consistentcy within a dentition

Answer 8

Timing is consistent within a dentition –children who erupt any
tooth early or late tend to acquire others early or late

Question 9

eruption of both sides coordinated?

Answer 9

Both sides should erupt at the same time- approximately

Question 10

different eruption sequences explain what crowding?

Answer 10

Different eruption sequences explain most frequently crowded teeth:

maxillary cuspids to the labial with small arches and mandibular second bicuspid with impacted second molars

Question 11

Local influences which hasten permanent tooth

eruption

Answer 11

localized pathosis:
periapical lesions (abscess), pulpitis and pulpotomy? of a primary molar)

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

Question 12

Local influences which slow permanent tooth

eruption

Answer 12

When  a primary tooth is extracted before active eruption of 
permanent tooth (i.e. before root formation)

Question 13

arch width change in maxilla
increased/decreased?
tied to?

Answer 13

The increases are tied to alveolar process growth (both dental eruption and vertical process growth)
both canine and PM erupt buccally which increases width

Question 14

when does arch width change

Answer 14

occurs during general growth “spurts”

Question 15

arch width changes in maxilla vs mandible

Answer 15

different for maxilla and mandible: divergent maxillary process translates into more arch width growth (mandible is convergent)

Question 16

dental factors of arch width changes

Answer 16

• Dental Eruption
▪ wider placement of the permanent teeth
▪ apposition of alveolar bone to support these teeth will result in increase in arch width

Question 17

intercanine distance in mixed dentition stage

Answer 17

will see increase during this time

Question 18

intercanine distance in perm dentition stage

Answer 18

will stop increase on mandible and decrease by .5mm on maxilla
overall larger on maxilla

Question 19

maxillary intercanine distance will increase during:

Answer 19

➢increases occur during growth spurts
➢increases occur during eruption of incisors
➢large increase occurs during eruption of the cuspids

Question 20

intercanine distance after canine eruption

Answer 20

NO SIGNIFICANT INCREASES IN INTERCANINE
WIDTH OCCUR IN EITHER THE MAXILLA OR
MANDIBLE AFTER THE ERUPTION OF PERMANENT
CANINES.

Question 21

when canines erupt they bring?

Answer 21

bone, can be used for treatment planning

Question 22

does arch perimeter change in perm dentition

Answer 22

yes

Question 23

Variations in Dimensional changes in the Dental Arches

Answer 23

➢changes are quite variable
➢different for males and females
➢different for maxillary and mandibular arches (maxillary easy to expand/more bone, mandible with less expansion and bone)

Question 24

max arch perimeter changes
variable?
sexes?

Answer 24

Variable(depends on pattern of tooth eruption)

Not difference between sexes

Question 25

Factors which limit loss of maxillary arch perimeter include:

Answer 25

greater labial angulation of incisors, greater increases in arch width and smaller leeway space

Question 26

the curve of spee with development

Answer 26

flat in primary dentition, begins to curve slightly with perm eruption due to differences in the anterior and posterior eruption times
curve allows for dynamic mandible movement

could become too curved with development

Question 27

third molars

Answer 27

• Prophylactic extraction of impacted teeth is a reasonable option.
• Extraction of third molars to avoid orthodontic relapse has a weak correlation, likely just an association