Management of the ectopic maxillary canine

Question 1

Normal maxillary canine

Answer 1

Palpable in the buccal sulcus at 9-10
years
Erupts 11-12 years
Width 7-9mm

Question 2

Ectopic maxillary canines

Answer 2

• Prevalence 1-3%
• More palatal than buccal (3:1… 1:1)
• 8% bilateral
• Associated with missing or diminutive
lateral incisors

Question 3

Aetiology

Answer 3

• Familial (most widely accepted)
• Long eruption path
• Guidance theory
-lateral would usually guide the canine down
• Crowding – chronology of eruption
• Narrow upper arch
• Lack of resorption of primary tooth
• Follicular disturbance
-rare

Question 4

Assessment

Answer 4

Clinical

Radiographic

Question 5

Clinical assessment

Answer 5

Palpation
Mobility of primary tooth
Space
Angulation of lateral

Question 6

Examination for canines

Answer 6

Canine bulge
-palpation buccally and then palatally (if not felt buccally)
-mobility of C
-space
Inclination of lateral incisor

Question 7

Radiographic assessment

Answer 7

Location of canine - parallax
Resorption of primary tooth (C)
-OPT
-Upper Standard Occlusal

Question 8

Principles of Parallax

Answer 8

Same
Lingual
Opposite
Buccal
*Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines*

Question 9

Complications

Answer 9

Root resorption
-biggest problem
Ankylosis
Cysts (rare)
Eruption under bridge or denture

Question 10

Intervention/ interceptive treatment

Answer 10

• Extraction of primary canine
• Before 11 years old
• 91% improvement if canine crown distal
to midline of lateral
• 64% if mesial to midline of lateral

Question 11

Management options

Answer 11

Leave
Extract
Orthdontic alignment
Transplant
-will depend on full history and examination

Question 12

Leave

Answer 12

Active caries/ high caries risk
-ortho not indicated
So ectopic won’t resorb any teeth, very far away

Question 13

Extract

Answer 13

Position of canine

-e.g. can’t move other teeth because canine in the way

Question 14

Ortho alignment

Answer 14

•Open exposure
-cut a window including bone, can suture pack including gauze to stop soft tissues growing back over
-can take up to 3 years
-GA
• Closed exposure (bond gold chain)
-expose canine but left soft tissues grow over
-GA
•(Create space – encourage natural eruption)
-new technique, not as commonly done
-quad helix expands arches plus push coil

Question 15

Displaced maxillary canines

Answer 15

Palatal impaction 85%
Buccal impaction 15%
(but diagnosis of position is not 10% accurate, CBCT suggests it may be 50:50)

Question 16

Displaced canines - palatal impaction

Answer 16

1. Leave in situ, monitor
2. Extract
3. Expose and align**
4. Transplant

Question 17

Problems as adults

Answer 17

Canines more likely to ankylose as they are being moved

-can end up without a C and with a stuck canine

Question 18

Open vs closed exposure

Answer 18

•No difference in periodontal or

surgical outcomes of open vs closed techniques

Question 19

Buccal impaction

Answer 19

Open exposure - apically repositioned flaps (only on buccal canines)
-reflect soft tissue buccaly
–repositioned apically
Closed exposure - gold chain

Question 20

Transplantation

Answer 20

• Too misaligned for orthodontics
• Canine ankylosed (not able to align with ortho)
• Patient not suitable for orthodontics
• Poor prognosis primary canines
• Adequate space
• No over-eruption of opposing teeth
• Too misaligned for orthodontics

Question 21

Prognosis of transplantation

Answer 21

After 5 year 72% had good prognosis

After 10 year 54& had good prognosis