Extraction of third molars 4 Flashcards
When is surgical extraction of third molars considered?
When tooth cannot be extracted with forceps alone
What are the basic principles in surgical removal of 8s?
Risk assessment
-> Good planning required - radiographs, equipment, consent, MH
Aseptic techniques- minimises infection/contamination
Minimal trauma to hard and soft tissues
What are the stages of surgical removal of an 8?
Anaesthesia (LA used even if patient sedated)
Access
Bone removal as necessary
Tooth division as necessary
Debridement
Suture
Achieve haemostasis
Post-operative instructions
What are the methods of anaesthesia for surgical removal of 8s?
Local Anaesthesia
IV Sedation & LA
General Anaesthetic
-> Depends on patient and difficulty of extraction
What flap is mainly used in surgical removal of 8s?
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)
What are the aims of raising a flap?
Provide maximal access with minimal trauma
-> remember that big flaps heal as quickly as small ones
How should the flap be incised?
Use scalpel in one continuous stroke to remove soft tissue and periosteum from bone
Minimise trauma to papillae
At which point should the raising of a flap be done from?
At the base of the relieving incision (triangular edge) where the bone is visible
What should be done to prevent tearing of tissue when raising a flap
Undermine / free anterior papilla before proceeding with reflection mesially/distally
Which instruments may be utilised in the process of reflecting a flap?
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
How should a flap be reflected?
Reflect with periosteal elevator firmly on bone
-> Avoid dissection occurring superficial to periosteum
-> Reduce soft tissue bruising / trauma
In which areas is reflection of flaps most difficult?
Papilla
Mucogingival junction
What are the aims of retraction?
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
What are the types of retractors?
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
When is bone removal considered?
Only when it would not be possible remove tooth in its entirety with elevators/forceps
What is used for bone removal?
Electric and saline cooled straight handpiece with round or fissure tungsten carbide bur
-> prevents necrosis/surgical emphysema
What are the uses of round and fissure burs in surgical removal of 8s?
Round bur- to create buccal gutter
Fissure- sectioning
How is a buccal gutter cut?
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)
Why is plenty of irrigation essential when removing bone?
Prevents necrosis
Helps maintain visibility
When is tooth division carried out?
If tooth is still impacted despite bone removal
How may a tooth be sectioned?
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
How is a horizontal section carried out?
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)
What can help you remove the roots after doing a horizontal section?
Splitting roots can be helpful to remove them
-> Put elevator in between roots where they have been sectioned then elevate roots separately
In what instances may a horizontal section be carried out?
If roots are separate (not fused)
What should be done immediately following the removal of a tooth?
After removal of tooth- check for all apices and that nothing has been left behind socket
What are the methods of debriding the socket?
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
What are Bone Mongeurs good for?
Removing bony spicules
What are the aims of suturing?
Approximate/reposition tissues
Cover bone
Prevent wound breakdown
Achieve haemostasis- Compress blood vessels
How are 3 sided flaps sutured after removing m3ms?
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
How are 2 sided flaps sutured after removing m3ms?
One interrupted across back of 7 and one at DRI
What are the clinical steps in surgical removal of Lower 8s?
- Give local- IDB, long buccal
- Gain access- scalpel to cut mucoperiosteal flap (decide on 2/3-sided)
- Retract ST- visualise the are you want to work in
- Attempt to elevate tooth
- If unable- bone removal (with suction)- cut buccal gutter from distal to mesial (narrow/deep)
- Attempt to elevate tooth- gives better application point
- If still unable to mobilise- mesioangular impaction (decoronate- with fissure bur)
- Try and elevate roots
- If still unable- split roots with vertical section and elevator (then elevate one at a time)
- Account for apices
- Debride and irrigate socket/flap
- Suture (usually resorbable- vicryl or velosorb)
- Achieve haemostasis and POI (written and verbal)
Which post op instructions are given to patient following surgical removal of Lower 8s?
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
POI continued:
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
When is a coronectomy considered?
If surgery is likely to risk IAN
What are the steps in a cornectomy?
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)
What are the principles of a coronectomy?
Remove all enamel
* Tooth roots must not be mobile after decoronation
* Smooth finish to decoronated tooth and surrounding bone
What are the drawbacks of coronectomy?
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
What is the review schedule following a coronectomy?
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
Are antibiotics prescribed routinely for coronectomies?
NO
What is different about removal of upper third molars compared to lowers?
Uppers are generally easier (although can be difficult if dense bone or limited mouth opening)
How are upper third molars removed?
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
What must you be careful of when removing upper 8s?
Tooth slipping and going down the throat
Fracturing tuberosity- support and be careful not to use excess force
What can be used to help us plan for and evaluate difficulty of upper third molar removal
Radiographs- look at roots
-> check size, number, shape, proximity to antrum
