18 - Mandibular fracture

Question 1

What are the clinical signs and symptoms fo mandibular fracture?

Answer 1

• pain, swelling, limitation of function
• occlusal derangement (occlusal step)
• numbness of lower lip
• loose or mobile teeth
• bleeding (FOM) / sublingual haematoma
• AOB
• facial asymmetry
• deviation of mandible to opposite side

Question 2

What causes AOB in mandibular fracture?

Answer 2

Bilateral subcondylar fracture

Question 3

What causes deviation of mandible to the opposite side?

Answer 3

Muscles contract and pull at fractured side

Question 4

How are mandibular fractures classified? 7

Answer 4

• soft tissue involvement
• number
• side
• site
• direction
• specific
• displacement

Question 5

How is soft tissue involvement in mandibular fracture classified?

Answer 5

• simple (ST not involved)
• compound (ST involved)
• comminuted (bone shattered ie gun shot)

Question 6

How is number in mandibular fracture classified?

Answer 6

• single
• double
• multiple

Question 7

How is side in mandibular fracture classified?

Answer 7

• unilateral
• bilateral

Question 8

How is site in mandibular fracture classified?

Answer 8

• condyle (intra/extra capsular)
• subcondylar
• coronoid
• ramus
• angle
• body
• parasymphyseal
• alveolar process

Question 9

How is direction in mandibular fracture classified?

Answer 9

• favourable
• unfavourable (encourages displacement)

Question 10

How are specific mandibular fractures classified?

Answer 10

• green stick fractures
• pathological fractures

Question 11

What are green stick fractures?

Answer 11

• common in children
• bone has high organic content
• bone fractures in “stringy” nature
• may not completely separate

Question 12

How is displacement in mandibular fracture classified?

Answer 12

• displaced
• undisplaced

Question 13

What factors cause displacement of mandibular fractures?

Answer 13

• direction of fracture line
• opposing occlusion
• magnitude of force
• mechanism of injury
• intact soft tissue (prevents displacement)
• other associated fractures

Question 14

What is the general management of mandibular fractures?

Answer 14

• clinical exam
• radiographic Assessment
• treatment
  • Fast
  • immediate OMFS contact
  • ABx for open wound
  • liquid diet
  • analgesics

Question 15

What makes up the radiographic assessment of mandibular fracture?

Answer 15

• two radiographs at right angles (OPT and PA mandible)
• CT

types:

• OPT : mandibular #
• PA mandible : posterior mandibular #
• Reverse Towne’s : Mand Condylar #

Question 16

Describe the soft tissue involvement in a fracture of a tooth bearing area.

Answer 16

• compound
• any fracture in the tooth bearing area is compound due to the communication with the PDL

Question 17

What are the basic principles of mandibular fracture management?

Answer 17

Control pain and infection

• reduction
• fixation

Question 18

Describe the management of an undisplaced fracture.

Answer 18

• no surgical treatment
• reduction, may not require fixation

Question 19

Describe the management of a displaced or mobile fracture.

Answer 19

• requires fixation
• closed reduction and fixation (IMF)
• ORIF

Question 20

Define IMF.

Answer 20

Intermaxillary fixation

Question 21

Define ORIF.

Answer 21

Open reduction and internal fixation

Question 22

How long is IMF treatment?

Answer 22

4-6 weeks

Question 23

How is IMF used in edentulous patients?

Answer 23

Denture is fixed to jaws

Question 24

What contraindicates IMF?

Answer 24

Epileptics

Question 25

What are the surgical approaches for fixation of condylar fracture?

Answer 25

• retro-mandibular
• raisdon (inferior border)
• preauricular
• bi-coronal flap
• endoscopic

Question 26

What are absolute indications for ORIF?

Answer 26

• bilateral subcondylar fracture with AOB
• displaced condylar fracture with trismus
• displaced fracture in middle cranial fossa
• displaced fracture with **occlusal derangement **
• displaced fracture with ramus shortening