Complications of Third Molar Removal

Question 1

what are the minor complications of surgical wisdom tooth removal?

Answer 1

– Pain, swelling, trismus
– Infection
– Fracture (mandible)
– Bleeding and bruising
– TMJ problems
– Temporary nerve damage
– Damage to other teeth
– Oral-antral communication

Question 2

what are the risk factors associated with wisdom tooth removal and fractured mandible

Answer 2

• Elderly, edentulous patients with atrophic mandible
• Pre-existing bone pathology
• Large bone defects
• Excessive use of force - Cryers, large elevators

Question 3

what is the major complication associated with 3rd molar removal?

Answer 3

Trigeminal Nerve Damage (Lingual and IAN)

Question 4

what is the incidence rates for trigeminal nerve damage?

Answer 4

IAN
* Temporary 5-7%
* Permanent 0.5% - 1%

Lingual
– Temporary 3-7%
– Permanent 0.3-0.5%

Question 5

give reasons a trigeminal nerve injury can occur

Answer 5

• Third Molar (majority)
• Implantology
• Other surgery, e.g orthognathic
• Trauma
• Needle Stick (neuropraxia)
• Endodontics

Question 6

why is surgical 3rd molar removal a common site for nerve injury?

Answer 6

it is in close proximity to lingual, long buccal, mylohyoid, inferior alveolar nerve

Question 7

how can we try to reduce risk of nerve damage when removing 3rd molars?

Answer 7

• IAN injuries are usually ‘drill injuries’
• Some are crush injuries – following forceps extraction – don’t use forceps for 8’s when close to IAN
• Low threshold for sectioning
• Elevator removal preferable
• Avoid lingual flaps
• Avoid lingual retraction

Question 8

name 3 types of reasons for nerve injury during 3rd molar removal?

Answer 8

Neuroma in continuity
Transaction
Crush injury

Neuroma – scar tissue stopping the nerves passing through

Question 9

what are the effects of trigeminal nerve injury?

Answer 9

• Complete loss of sensation to half the anterior tongue and/or chin/lip
• Paraesthesia – Reduced sensation
• Dysaesthesia – Pain, tingling, burning
• Allodynia (painful response to non-painful stimuli)
• Loss of taste

Question 10

what is the current management for a lingual nerve injury?

Answer 10

surgically carry out nerve repair
- patients tend to have an improvement in symptoms but remember it will never return to normal
- not all patients suitable for this procedure

Question 11

how do we measure improvements in nerve damage

Answer 11

SENSORY TESTING:
- light touch stimuli
- pin prick stimuli
- gustatory stimuli
- two point discrimination

Question 12

what are the indications for surgical intervention?

Answer 12

• Persistent anaesthesia
• Dysaesthesia/Pain

Question 13

how can we surgically treat IAN damage

Answer 13

Need to remove buccal plate and then:
* Can remove bony obstruction
* Can remove bony compression
* Can remove remove soft tissue tethering/tension
* Can remove ‘neuroma’ - decreased dysaesthesia

Question 14

Does IAN decompression surgery work?

Answer 14

– Reduces the number of patients with dysaesthesia and improves level of sensartion
– Gives no improvement in some patients
– Never results in complete recovery
– We cannot predict who will benefit
We suggest that this operation should only be offered to patients with severe symptoms

Question 15

how can we reduce nerve damage due to LA?

Answer 15

• Face bevel laterally
• Dont use Articaine for ID blocks (lidocaine nerve injuries are more likely to recover)
• Avoid mental area
• If pt feels electric shock sensation – with draw needle do not carry-on injecting as can cause damage to nerve

Question 16

what do we look at when we have a radiograph of 3rd molar?

Answer 16

• Type of impaction
• Depth of tooth within bone
• Crown form
• Root form and number
• Coronal or root pathology
• Other pathology (cyst, caries in 2nd molar)
• Relationship with mandibular canal (IAN) or maxillary sinus