ORTHO ectopic canines

Question 1

what factors contribute to ectopic canines?

Answer 1

family history
females>males
class II div 2
hypodontia/ microdontia
late presentation
pathology - root resorption

Question 2

what is interceptive treatment for ectopic canines?

Answer 2

extraction of Cs

Question 3

what does the success of interceptive treatment for ectopic canines rely on?

Answer 3

the portion of the root of the lateral incisor overlap with the ectopic canine
- works best in uncrowded cases

Question 4

if the interceptive treatment of ectopic canine doesnt work, what techniques can be used?

Answer 4

open exposure
closed exposure
surgical removal of canines

Question 5

what is the risk of leaving ectopic canines?

Answer 5

cystic change (the tooth will therefore need to be removed)
canine appears later on in life

Question 6

what guidelines do we follow regarding ectopic canines?

Answer 6

Royal College of Surgeons - management of the palatally ectopic maxillary canine

Question 7

in ortho, when do you take xrays?

Answer 7

confirm unerupted teeth
locate unerupted teeth
pathology
root morphology
assess skeletal pattern
monitor tx changes

Question 8

what type of radiographs do you take to locate ectopic canines?

Answer 8

vertical parallax - DPT + max occlusal
horizontal parallax - DPT + periapical

Question 9

when do canines begin to develop?

Answer 9

4-5 months of age

Question 10

when does crown calcification of the canines begin?

Answer 10

6-7 years

Question 11

when do upper canines erupt?

Answer 11

11-12

Question 12

when do lower canines erupt?

Answer 12

10-11

Question 13

what percentage of the caucasian population experience impacted upper canines?

Answer 13

2-3%

Question 14

when do we start examining for the canines? and how do we do this?

Answer 14

9 years old
palpate buccally and palatally

Question 15

when chosing to not treat an ectopic canine, what must be performed routinely?

Answer 15

radiographs

Question 16

describe in lay terms, open exposure for ectopic canines?

Answer 16

a small window of gum and bone is removed over the buried tooth to help it grow into the mouth
sometimes a gold chain or brace attachment is stuck on to the tooth either at the time of the operation or later on in the treatment
fixed braces are used to bring the canine tooth into the correct position
you may need to have other teeth removed to make enough space for the canine

Question 17

what does an open exposure operation involve for the patient?

Answer 17

general or local anaesthetic
stiches after the operation and possible something to dress the canine

Question 18

how long does open exposure of an ectopic canine take?

Answer 18

more than 2 years

Question 19

does open exposure for ectopic canines always work?

Answer 19

usually, however in rare cases the tooth is fused to bone and will not move - if this happens, the tooth must be removed and the pt may require further dental tx

Question 20

when may the option of complete removal of an ectopic canine be considered?

Answer 20

pt does not want to wear a fixed brace
the rest of the teeth are straight with no gaps
the buried tooth is in a poor position
the buried tooth is causing problems

Question 21

why may 3s be buccally displaced?

Answer 21

as it is the last tooth to erupt anterior to the 6, if the upper arch is crowded

Question 22

how are ectopic canines assessed?

Answer 22

palpation
inclination of the 2
radiographs: DPT + IO view or 2 IO views

Question 23

when chosing to maintain a C, leaving the unerupted canine under radiographic view, what must the patient be warned of?

Answer 23

there must be no evidence of cystic change/ resorption
removal of 3 can be left until GA is required e.g., for extractions of 8s
patient must understand that C will eventually be lost, necessitating a prosthesis

Question 24

state the circumstances in which exposure and ortho alignment is feasible?

Answer 24

1. canine is in a favourable position
2. sufficient space available for the 3, or can be created
3. pt is willing to undergo surgery and prolonged ortho rx (2 years)