Management of Third Molars

Question 1

What age do third molars tend to erupt?

Answer 1

18-23

Question 2

What is the definition of impacted tooth?

Answer 2

One which is prevented from reaching its normal position by presence of structure - can be adjacent tooth/ ramps/ overlying tissue

Question 3

Two types of un-erupted impacted teeth?

Answer 3

Partially enclosed within bone

Full enclosed in bone

Question 4

Associated problem with impacted 8s?

Answer 4

Abnormal position = cheek biting
Pathology 2nd and 3rd molar
Periodontal problem
Pericoronitis
Resorption
Cyst formation

Question 5

Less common problems of impacted 8s?

Answer 5

Difficulty OH

Crowding lower incisors

Question 6

Why do impacted 8s cause pathology?

Answer 6

Hard to clean due to angulation - caries, and apical pathology

Question 7

What is pericoronitis?

Answer 7

Inflammation of soft tissue around the crown of partially erupted tooth
Caused by bacterial infection and/ or trauma

Question 8

Symptoms of pericoronitis?

Answer 8

Pain and discomfort
Soft tissue swelling
Difficulty function - eat, swallow, open
Tenderness
Unpleasant taste/ smell
Can feel unwell

Question 9

Signs of pericoronitis?

Answer 9

Inflammation is soft tissue surrounding crown
Localised intra-oral swelling
Pus +-
Local lymphadenopathy +-
Facial swelling +-

Question 10

How to manage pericoronitis?

Answer 10

Irrigation - saline/ chlorhexidine
Drain pus if present
Formal review

Question 11

Should ab be used for pericoronitis?

Answer 11

Only if spreading infection or compromised pt

Metronidazole 400mg

Question 12

How to assess a 3rd molar based on eruption?

Answer 12

Likely to erupt and be in function - monitor

Unlikely to erupt - if problematic consider XLA, if not monitor

Question 13

NICE Guidelines re XLA 8s?

Answer 13

Routine practice of prohylactic removal of pathology- discontinued
XLA/ surgical removal limited to pt w/ evidence pathology

Plaque formation is RF not indication
Hx and justification always justified

Question 14

NICE guidelines re pericoronitis?

Answer 14

Degree of severity and recurrence rate influences decision

First episode- unless very severe = not indication?

Question 15

What is rationale behind guidelines for XLA?

Answer 15

Potential savings
Reducing weight lists
Not ethical expose pt to unnecessary tx

Question 16

Why is prophylactic removal proposed?

Answer 16

Prevent crowding
Reduce complications/ pathology
Pt better cope when young - less complications/ bone density

Question 17

What should be included in radiographic assessment prior XLA?

Answer 17

Diagnosis
type impaction
depth of tooth within bone
crown form
root number and form
pathology
relationship ID canal

Question 18

Most appropriate radiograph?

Answer 18

sectional OPT

Need all of tooth and mandibular canal

Question 19

What are the 5 type of angulation?

Answer 19

Vertical
Mesioangular
Horizontal
Distoangular
Bucco or linguo-

Question 20

What type of angulation is easiest to remove?

Answer 20

Vertical

But risk of periocoronitis

Question 21

Which are difficult to remove and have high risk of food packing?

Answer 21

Mesio-angular
Horizontal

Risk caries 2nd molar

Question 22

Which is the most difficult?

Answer 22

Disto-angular

Ramus obstruct XLA and close proximity ID canal

Question 23

What are the root patterns seen 8s?

Answer 23

Fused and conical
Straight and separate
Pincer shape
Complex

Question 24

Options available with pathological 8s?

Answer 24

Removal
Monitor
Operculectomy
Coronectomy

Question 25

Management options for 8s?

Answer 25

LA
LA + sedation
GA

Question 26

What is technique for coronectomy?

Answer 26

Raise buccal flap
Cut 45 degree to crown
Fissure bur - reduce 3mm below alveolar crest
Periosteal release and primary closure

Question 27

What pt shouldn’t have coronectomy?

Answer 27

If close proximity IAN
If no evidence active infection/ tooth mobility
Horizontal/ severe mesioangular - increased risk of IAN damage
Pt w/ co-morbidities