Ectopic canines and unerupted centrals

Question 1

What is interceptive orthodontics?

Answer 1

Any procedure that will reduce or eliminate the severity of a developing malocclusion

Question 2

At what age can you start to buccally palpate the canines?

Answer 2

9/10

Question 3

What is the aetiology of ectopic canines?

Answer 3

Long path of eruption
Genetic link - association with other dental anomalies - class II/II, missing/ peg laterals
F > M
Crowding - canine last tooth to erupt
Ectopic position of tooth germ

Question 4

What age would you extract a C to promote eruption of 3’s?

Answer 4

Prime age 10-13

Question 5

When is interceptive extraction of a C likely to be successful in ectopic canines?

age & other things

Answer 5

When patient is between 10-13
When the canine is distal to the midline of the upper lateral incisor
When there is sufficient space available

Question 6

What are the treatment options for an ectopic canine?

Answer 6

Accept/ do nothing
Interceptive extraction of C’s
Surgically expose and align the canine
Surgically extract
Auto-transplantation

Question 7

What are the risks of leaving the ectopic canine?

Answer 7

Cyst formation
More likely to ankylose over time
Resorption of the roots of adjacent teeth
Resorption of canine crown
Eventual loss of the deciduous C
Ectopic canine may never erupt

Question 8

When would an ectopic canine be indicated to surgically extract?

Answer 8

Position - canine is not deemed align-able
If root resorption of lateral incisors is starting to occur
If there is NO significant risk of damaging adjacent teeth during procedure

Question 9

Describe the process of an open exposure of an ectopic canine?

Answer 9

Lift a flap over canine - make a window over where canine is- may have to remove bone.
Replace flap and suture back.
Place a pack over where the window has been cut.
Pack left for 10 days
Either left to spontaneously erupt or gold chain bonded at a later date

Question 10

What is the purpose of the pack in an open exposure?

Answer 10

So you do not get healing of the mucosa over the open window

Question 11

What is a closed exposure in orthodontics?

Answer 11

Expose the canine - put orthodontic traction hook and attach a gold chain to pull down
Suture back together

Question 12

When is a radiograph indicated for unerupted canines?

Answer 12

Radiograph if unable to palpate by 11 years old

Question 13

What two radiographs do you need to determine location of an ectopic canine?

Answer 13

PARALLAX
Horizontal
- 2 PAs
- PA & AMO

Vertical
- OPT and AMO
- OPT and PA

Question 14

What are most common reasons for un-eruption of maxillary central incisors?

Answer 14

Supernumeraries
Trauma
EARLY extraction of primary teeth
LATE exfoliation/ extraction of primary teeth - quite close to expected exfoliation date
CLP

Question 15

In what scenarios would a central incisor be deemed as “unerupted”?

Answer 15

If the contralateral tooth erupted more than 6 months ago
Maxillary incisors remain unerupted for more than one year after mandibular
If there is significant deviance from normal eruption sequence e.g. laterals erupted before centrals

Question 16

How would an unerupted maxillary central incisor be treated if the cause was supernumeraries?

Answer 16

Remove primary teeth and supernumeraries
Create/ maintain space
Monitor for 12 months to see for spontaneous eruption - if patient <9 (immature root apex)

If STILL fails to erupt OR patient >9

Expose central incisor, bond gold chain and align.