Extraction of third molars 4

Question 1

When is surgical extraction of third molars considered?

Answer 1

When tooth cannot be extracted with forceps alone

Question 2

What are the basic principles in surgical removal of 8s?

Answer 2

Risk assessment
-> Good planning required - radiographs, equipment, consent, MH

Aseptic techniques- minimises infection/contamination

Minimal trauma to hard and soft tissues

Question 3

What are the stages of surgical removal of an 8?

Answer 3

Anaesthesia (LA used even if patient sedated)
Access
Bone removal as necessary
Tooth division as necessary
Debridement
Suture
Achieve haemostasis
Post-operative instructions

Question 4

What are the methods of anaesthesia for surgical removal of 8s?

Answer 4

Local Anaesthesia

IV Sedation & LA

General Anaesthetic

-> Depends on patient and difficulty of extraction

Question 5

What flap is mainly used in surgical removal of 8s?

Answer 5

Buccal mucoperiosteal- starting around the gingival margin of 7 (3 sided)

-> lingual may be used depending on clinician preference and clinical situation (risks lingual nerve)

Question 6

What are the aims of raising a flap?

Answer 6

Provide maximal access with minimal trauma

-> remember that big flaps heal as quickly as small ones

Question 7

How should the flap be incised?

Answer 7

Use scalpel in one continuous stroke to remove soft tissue and periosteum from bone

Minimise trauma to papillae

Question 8

At which point should the raising of a flap be done from?

Answer 8

At the base of the relieving incision (triangular edge) where the bone is visible

Question 9

What should be done to prevent tearing of tissue when raising a flap

Answer 9

Undermine / free anterior papilla before proceeding with reflection mesially/distally

Question 10

Which instruments may be utilised in the process of reflecting a flap?

Answer 10

Mitchell’s trimmer- spoon end/sharp end

Howarth’s periosteal elevator

Ash Periosteal Elevator- flat end, useful for raising flap

Curved Warwick James elevator- good for lifting papillae

Question 11

How should a flap be reflected?

Answer 11

Reflect with periosteal elevator firmly on bone
-> Avoid dissection occurring superficial to periosteum
-> Reduce soft tissue bruising / trauma

Question 12

In which areas is reflection of flaps most difficult?

Answer 12

Papilla

Mucogingival junction

Question 13

What are the aims of retraction?

Answer 13

Access to operative field
-> Flap design facilitates retraction

Protection of soft tissues
-> Take care not to crush underlying tissue

Atraumatic/ passive- avoid adjacent structures like nerves

Question 14

What are the types of retractors?

Answer 14

 Rake- has spikes which hooks under tissue (holds well, does not slip)

 Minnesota- wide based, sits on bone, holds soft tissues behind, shiny surface reflects light into surgical area

 Howarth’s periosteal elevator

Question 15

When is bone removal considered?

Answer 15

Only when it would not be possible remove tooth in its entirety with elevators/forceps

Question 16

What is used for bone removal?

Answer 16

Electric and saline cooled straight handpiece with round or fissure tungsten carbide bur
-> prevents necrosis/surgical emphysema

Question 17

What are the uses of round and fissure burs in surgical removal of 8s?

Answer 17

 Round bur- to create buccal gutter

 Fissure- sectioning

Question 18

How is a buccal gutter cut?

Answer 18

Aim for it to be as narrow and deep as possible (as deep as bur itself)
-> allows application point

Go from distal to mesial, hold in close contact to tooth (this way the soft tissues are protected and bur is controlled)

Question 19

Why is plenty of irrigation essential when removing bone?

Answer 19

Prevents necrosis

Helps maintain visibility

Question 20

When is tooth division carried out?

Answer 20

If tooth is still impacted despite bone removal

Question 21

How may a tooth be sectioned?

Answer 21

 Horizontal- remove crown, to allow space to elevate roots
-> cut across width of crown (be careful that drill does not slip)

 Vertical- sectioned into mesial and distal parts

Question 22

How is a horizontal section carried out?

Answer 22

Drill into the tooth only going as far as height of bur, from mesial to distal (or VV)

Use Warwick James in channel created with back and forth rotational movement to crack crown off (warn patient)

Question 23

What can help you remove the roots after doing a horizontal section?

Answer 23

Splitting roots can be helpful to remove them
-> Put elevator in between roots where they have been sectioned then elevate roots separately

Question 24

In what instances may a horizontal section be carried out?

Answer 24

If roots are separate (not fused)

Question 25

What should be done immediately following the removal of a tooth?

Answer 25

After removal of tooth- check for all apices and that nothing has been left behind socket

Question 26

What are the methods of debriding the socket?

Answer 26

Physical:
-> Bone file or handpiece to remove sharp bony edges
-> Mitchell’s trimmer or Victoria curette to remove soft tissue debris

Irrigation:
-> Sterile saline into socket and under flap (do again before repositioning)

Suction:
-> Aspirate under flap to remove debris
-> Check socket for retained apices, sharp edges, bony spicules

Question 27

What are Bone Mongeurs good for?

Answer 27

Removing bony spicules

Question 28

What are the aims of suturing?

Answer 28

Approximate/reposition tissues

Cover bone

Prevent wound breakdown

Achieve haemostasis- Compress blood vessels

Question 29

How are 3 sided flaps sutured after removing m3ms?

Answer 29

 One suture at DRI and one to replace MRI (you may put 2 sutures here- if gap or you can see underlying bone)

*Optionally you may place suture at papillae if this is free

Question 30

How are 2 sided flaps sutured after removing m3ms?

Answer 30

One interrupted across back of 7 and one at DRI

Question 31

What are the clinical steps in surgical removal of Lower 8s?

Answer 31

1. Give local- IDB, long buccal
2. Gain access- scalpel to cut mucoperiosteal flap (decide on 2/3-sided)
3. Retract ST- visualise the are you want to work in
4. Attempt to elevate tooth
5. If unable- bone removal (with suction)- cut buccal gutter from distal to mesial (narrow/deep)
6. Attempt to elevate tooth- gives better application point
7. If still unable to mobilise- mesioangular impaction (decoronate- with fissure bur)
8. Try and elevate roots
9. If still unable- split roots with vertical section and elevator (then elevate one at a time)
10. Account for apices
11. Debride and irrigate socket/flap
12. Suture (usually resorbable- vicryl or velosorb)
13. Achieve haemostasis and POI (written and verbal)

Question 32

Which post op instructions are given to patient following surgical removal of Lower 8s?

Answer 32

Bruising- everyone bruises to different degree
 Can depend on difficulty of extraction and patients normal healing response

Infection- warn about signs
 If pain, swelling is present after 3 days
 If pus present
 ABP not done routinely but may be prescribed for infections

Jaw stiffness- lengthy procedure and far back in mouth
 Stick to soft diet and limit mouth opening

IDB- lasts for 3 hours
 Tongue and buccal tissues- sensation returns first
 If after numbness wears off there is still an area that remains numb (contact)

Warm salty water- boil kettle and add salt
 2-3 times per day
 Rinse out 6-8 hours to avoid risk of dislodging blood clot

Question 33

POI continued:

Answer 33

Reinforce smoking cessation- 48 hrs at least (good opportunity to quit)

No vigorous exercise- no running upstairs

Eating- other side of mouth, do not eat until LA wears off

Take pre-emptive analgesia- paracetamol and ibruprofen mixture is best
 Pain peak- 24-48 hours (then analgesia when required)

Swelling- around socket and cheek (normal)
 Use ice pack (limited evidence)
 If swelling spreads into jaw, neck, eye (contact us ASAP)

Bleeding is normal to be on/off for first 72 hrs
 Bite on gauze
 LA wearing off and eating/drinking are likely to start bleeding up again

Question 34

When is a coronectomy considered?

Answer 34

If surgery is likely to risk IAN

Question 35

What are the steps in a cornectomy?

Answer 35

Remove crown of 8 and leave roots behind:
1. Flap design will be the same
2. Transect tooth 3-4mm below level of enamel into dentine
3. Elevate and lever crown without mobilising roots
4. Leave pulp in place untreated
5. Irrigate
6. Replace flap (can be open/closed completely)

-> If necessary – further reduction of roots with a rose head bur to 3-4mm below alveolar crest (not always possible)

Question 36

What are the principles of a coronectomy?

Answer 36

Remove all enamel
* Tooth roots must not be mobile after decoronation
* Smooth finish to decoronated tooth and surrounding bone

Question 37

What are the drawbacks of coronectomy?

Answer 37

 If roots mobilise during procedure - they cannot be left behind due to infection risk

 Roots left behind may become infected/symptomatic- another surgical procedure is required

 Dry socket still possible

*Migration of roots can occur- may make their removal safer at later stage

Question 38

What is the review schedule following a coronectomy?

Answer 38

Review 1-2 weeks

Further review 3-6 months then 1 year
-> Some review at 2 years but most discharge back to GDP after 6 months or 1 year review

Radiographic review – 6 months or 1 year (or both)
-> Thereafter if symptomatic- take an immediate or 1 week post op radiograph

Question 39

Are antibiotics prescribed routinely for coronectomies?

Answer 39

NO

Question 40

What is different about removal of upper third molars compared to lowers?

Answer 40

Uppers are generally easier (although can be difficult if dense bone or limited mouth opening)

Question 41

How are upper third molars removed?

Answer 41

Can often be done with just an elevator

->Warwick James- fits into space between 7/8 (active side on 8) and then rotated clockwise and anti-clockwise- tooth will start to mobilise

-> use 3rd molar bayonets to remove

Question 42

What must you be careful of when removing upper 8s?

Answer 42

Tooth slipping and going down the throat

Fracturing tuberosity- support and be careful not to use excess force

Question 43

What can be used to help us plan for and evaluate difficulty of upper third molar removal

Answer 43

Radiographs- look at roots
-> check size, number, shape, proximity to antrum