02.20 development disturbances in eruption and exfoliation

Question 1

Displacement or malposition of erupting tooth

Answer 1

Ectopic Eruption

Question 2

what is the most common cause of ectopic eruption?

Answer 2

crowding

-other causes: over-retained primary teeth, supernumerary teeth, missing teeth, infection and caries

Question 3

which tooth is the most common for ectopic eruption?

Answer 3

Molars: most common in maxillary 1st molars

Question 4

how many ectopicly erupted teeth self correct?

Answer 4

60-70% if the child is less than 7 (at least dental age, so look at the other three molars)

Question 5

self correction is rare for ectopic eruption if:

Answer 5

child is greater than 7

• perm molar locked in pulp of 2nd primary molar
• mesial angulation of perm molar severe (>3mm)
• 2nd primary molar is mobile

Question 6

what is the incidence of ectopic eruption?

Answer 6

5% (22% in pts with cleft lip/palate)

Question 7

Ectopic Eruption treatment: if 1 permanent molar is UNERUPTED and locked under 2nd primary molar…

Answer 7

extraction of 2nd primary molar is indicated with subsequent need for space regaining after the 1st permanent molar erupts

Question 8

Ectopic Eruption treatment: if 1st permanent molar is partially erupted:

Answer 8

• disking distal surface of “E”
• using an orthodontic separator, brass wire, or spring loaded device to unlock “6”
• halterman appliance

Question 9

other than molars, what other teeth common undergo ectopic eruption?

Answer 9

mandibular lateral incisors

Question 10

what is the consequence of ectopic eruption of mand lateral incisor?

Answer 10

the lateral incisor erupts and resorbs root of primary canine,
-Result: early exfoliation of primary canine with subsequent midline shift to the affected side and little space available between permanent lateral incisor and primary 1st molar

Question 11

treatment for ectopic eruption of lateral mand incisors:

Answer 11

1-extract contra lateral primary canine to allow possibility of normalizing midline
2-make a lower lingual holding arch to keep permanent incisors from tipping lingually
3-ortho and/or serial extractions

Question 12

ectopic eruption of central incisors; txt

-shark teeth

Answer 12

• if maxillary, ext primary incisors asap

- if mandibular, let tooth exfoliate, once 8-8.5 extract

Question 13

fusion of tooth to bone

Answer 13

ankylosis

Question 14

diagnosing ankylosis

Answer 14

• tooth remains stationary in the alveolus and the adjacent areas continue to grow giving the effect of the tooth “submerging”
• lack of mobility
• “dull” sound to percusssion(?)

Question 15

tooth remains stationary in the alveolus and the adjacent areas continue to grow making it look like the tooth is “submerging”

Answer 15

ankylosis

• lack of mobility
• “dull” sound on percussion

Question 16

when part of the bone is attached to the tooth when it erupts

Answer 16

eruption sequestration

Question 17

when do permanent incisors erupt?

Answer 17

when 1/2 or more of root is complete

Question 18

when do permanent canines and pms erupt?

Answer 18

when 2/3 or root is complete

Question 19

permanent tooth on one side is erupted and contra-lateral primary tooth not replaced within six months

Answer 19

(over)retained primary teeth

Question 20

causes of retained primary teeth (causes of delayed eruption of permanent teeth)

Answer 20

• trauma leading to primary tooth infection and retention
• pathology
• syndromes

Question 21

txt of retained primary teeth

Answer 21

extraction, if permanent tooth doesn’t erupt within six months, ortho, surgically expose with button/bracket

Question 22

causes of ankylosis

Answer 22

permanent teeth: trauma, complication of reimplantation of avulsed tooth or following luxation injuries
-primary teeth: incidence 7-14%

Question 23

most commonly ankylosed primary tooth

Answer 23

lower 1st primary molar

Question 24

txt for ankylosed teeth

Answer 24

don't really do anything for primary teeth but can
-luxate and try to free the tooth
-bonded resin build up
-extraction and space maintenance
PERMANENT teeth: luxation, extraction

Question 25

treatment of an abnormal maxillary frenum

Answer 25

• it can cause a diastima is very fibrous

- DO ORTHO FIRST before trying frenectomy

Question 26

thumb sucking/pacifier habit, when can they stop and still have teeth self correct?

Answer 26

if skeletal, it will correct if they stop by four yrs old, if open bite is skeletal, needs ortho