Orthodontics & Oral Surgery

Question 1

List soft tissue surgical procedures which are carried out for orthodontic tx. (3)

Answer 1

• Frenectomy (less common – modify more often)
  – V to Y frenoplasty
  – Z-plasty
• Impacted canines: soft tissue exposure without bone removal
  – Buccal apically repositioned flap
  – Palatal open exposure
• Impacted premolar exposures (usually just need soft tissue exposure and no bone removal)

Question 2

List hard tissue surgical procedures which are carried out for orthodontic tx. (7)

Answer 2

• Impacted canines: most need bone removal
  – Buccal apically repositioned flap with bone removal
  – Palatal open exposure with bone removal
  – Buccal or palatal closed exposure with gold chain attachment
  – Extraction
• Premolars: can need bone removal
  – Extraction
  – Exposure of impacted premolars with bone removal
• Other (simple) extractions
• Submerged retained primary teeth
• Implants
• Mini-implants
• Orthognathic surgery

Question 3

When is it indicated to leave and monitor an impacted canine? (6)

Answer 3

when there is;
- Reasonable aesthetics
- Bilateral (symmetry) or unilateral (premolar moved into space)
- Tooth harmless to other teeth
- Not interfering with orthodontic tx
- No pathology
- Px not keen on surgery

Question 4

What are the risk of not treating an unerupted canine? (4)

Answer 4

• Can erupt later in life
• Infection risk (esp if communication present)
• Dentigenous follicular cyst
• Damage to the adjacent teeth

Question 5

What are the tx options for a impacted canine? (3)

Answer 5

leave and monitor

extract

surgical exposure and orthodontic alignment

canine transplant

Question 6

When would an impacted canine be extracted?

Answer 6

when the position of the canine would not be compatible/suitable with bringing it down and aligning

Question 7

What surgical procedures can aid orthodontic alignment after surgically exposing the impacted canine? (2)

Answer 7

• Mini-implants
• Corticotomy

Question 8

When is a minimal surgical exposure used for impacted canines?

Answer 8

when the canine is in the line of arch and close to the surface. (no flap raised)

Question 9

what are the indications for canine transplant? (4)

Answer 9

• When we cannot reasonably get a result by exposure and traction
• There is a potential for damage to other teeth
• Space is available or can be made available without premolar extraction
• The older patient who is seeking a quick solution

Question 10

What happens to failed transplanted canines?
what are the implications of this.

Answer 10

Ankylosis - Very destructive and hard to remove and can lead to loss of bone = unable to have implant (need bone graft)

Question 11

Why are buccally placed canines less favourable than palatally placed? (3)

Answer 11

As they are Commonly present in the unattached gingivae on the buccal aspect

= more red gingival margin when aligned compared to adjacent teeth
= gingivae is delicate and can recede

(Can’t just leave an open exposure buccally as this causes the unattached gingival margin to erupt with the tooth)

Question 12

what are kissing canines?

Answer 12

Canine crosses the midline and contacts the canine on the opposite side

Question 13

What commonly causes impacted premolars?

Answer 13

ealy loss of E’s

Question 14

What is an apically repositioned flap used for?

Answer 14

preserving the attached mucosa in an impacted buccally placed canine

Question 15

Describe what is involved in an apically repositioned flap and why it is used.

Answer 15

We move the attached mucosa apically so that when the buccally placed canine moves down into the line of the arch it comes down with attached mucosa = better aesthetics and less delicate

Question 16

Describe what occurs in a submerged primary tooth.

Answer 16

becomes ankylosed to surrounding bone

Question 17

What are the risks of submerged teeth? (2)

Answer 17

• Damage to the permanent successor
• Push the primary tooth more apically into the maxillary sinus

Question 18

What is the tx option for submerged teeth?

Answer 18

Must be surgically removed with a flap and bone removal
Cant get the forceps on the crown

Question 19

why are implants useful in orthodontics?

Answer 19

During orthodontic treatment, the planned movement of one tooth or group of teeth causes reciprocal movement of the teeth that are used for anchorage
- Implants provide the qualities of an ideal orthodontic anchor

Question 20

What are the advantages of using implants for orthodontic anchorage? (5)

Answer 20

1. Patient compliance unnecessary
2. Absolute anchorage as there is no periodontal ligament
3. Easily used under a variety of treatment modalities
4. Easily placed
5. Removable, if necessary

Question 21

what type of implants are used in orthodontics?
what is the advantage of this implant?

Answer 21

Mini implant made of stainless steel – don’t osteointegrate

Question 22

What is the main advantage of a palatal mini implant?

Answer 22

removes need for headgear

Question 23

When is a corticotomy used?

Answer 23

when teeth are reluctant to move during orthodontics

Question 24

What is the aim of a corticotomy?

Answer 24

to weaken the dense cortical bone

Question 25

How do we carry out a corticotomy?

Answer 25

Drilling holes in the buccal and/or lingual cortical plates