Surgical Principles and Technique

Question 1

What are the indications for GA?

Answer 1

• acute infection unable to treat using regional block anaesthesia
• operation involves multiple quadrants, is lengthy and/or difficult
• patients with very poor co-operation

Question 2

What constitutes a good flap design?

Answer 2

• Access
• Maintain good blood supply (base wider than margin)
• Full thickness incision
• Always consider anatomical structures e.g. mental nerve and lingual nerve

Question 3

What are the complications of cutting a flap?

Answer 3

1. Flap necrosis - ensure base is wider than margin and the length is no more than twice the width
2. Flap dehiscence (separation) - avoid by ensuring clean cuts over healthy bone, minimising tension
   Leads to pain, bone loss, infection and scarring
3. Flap tearing - make incisions long enough to give adequate access

Question 4

What are the different types of flap design?

Answer 4

1. One-sided - good blood supply, poor access
   Only used for palatally impacted teeth or superficial roots
2. Two-sided
3. Three-sided - better access, poorer blood supply

Question 5

Mucoperiosteal flap is reflected using what instrument?

Answer 5

Periosteal elevator:

Mitchell’s trimmer or Howarth’s elevator

Question 6

The tissues are reflected using what instrument?

Answer 6

Bowdler-Henry rake

Avoid lifting movements - tear the tissue

Question 7

What is the purpose of bone removal in MOS?

Answer 7

1. Reveal the tooth
2. Create a point of application
3. Access the furcation
4. Relieve impaction