Treatment Planning for M3M Flashcards
What was the aim of NICE guidelines for the treatment of M3Ms?
to limit surgical treatment of M3M to symptomatic patients
the guidance stressed the discontinuation of prophylactive surgical removal of impacted 3rd molars
What is the baseline test for assessing risk of IANI injury following M3M removal?
OPT
According the NICE guidelines, state some indications for M3M surgery
Pathology e.g.
* unrestorable caries
* untreatabe pulpal or periapical pathology
* cellulitis
* abscess
* osteomyelitis
* resorption of tooth or adjacent teeth
* diseases of the follicle including cysts or tumours
* teeth impeding surgery
* teeth in field of tumour resection
* severe or multiple episodies of pericoronitis
The SIGN guidance has some indications for prophylactic removal. Give some examples of cases where prophylactic removal may be appropriate
- pre-radiotherapy
- cardiac surgery
- periodontal disease associated with the 2nd molar due to position of the 3rd molar
- patients who have occupations or lifestyles that inhibits access to regular dental care
- when there is caries present in the 2nd molar which cannot be restored without the removal of the 3rd molar
where the risks of retaining the wisdom tooth outweigh the risks of removal
Where do the NICE and SIGN guidelines differ with regards to indications for removal of M3Ms? What has been the impact of this difference?
the NICE guidelines for indication does not include the removal of 3rd molars in order to render the 2nd molars restorable like the SIGN guidelines recommend
since implementation of the NICE guidelines, distal caries in the M2Ms has increased from 5% to 19%
What was the result of the Supreme Court judgement following Montgomery V Lancanshire Health board case?
clinicians must divulge any material risk involved in the treatment plan and discuss reasonable alternatives
What are the risks of surgical removal of M3Ms?
- post-operative pain
- swelling
- trismus
- infection
- dry socket
- IAN damage
- lingual nerve damage
- fracture of the mandible
What are the clinical presentations of IANI ?
temporary or permanent altered sensation to the lip, chin and teeth on that side
What are the clinical presentations of lingual nerve injury?
- temporary or permanent altered sensation to the anterior part of the tongue
- altered taste sensation to the ipsilateral anterior 2/3 of the tongue
What bacteria have been implicated in the development of dry socket? What is their proposed MOA?
Treponema denticola and other spirochetes
release fibrinolytic enzymes that break down the clot
What are the radiographic warning signs on an OPT for increased IANI risk?
- interruption of white lines
- darkening of the root
- deflected root
- diversion of the IAN canal
- narrowing of the root
- juxta-apical area
Surgical removal has a 9x greater risk of dry socket than conventional forceps extraction. True or false
true
Outline some newer techniques that can be used for the prevention of dry socket
- plasma rich in growth factors
- low level laser therapy
How is a surgical site infection diagnosed?
- presence of suppuration
- lymphadenopathy
- systemic signs of infection
When do mandibular fractures associataed with M3M removals occur and how?
2-3 weeks post-operatively
they often occur during mastication
When is altered taste sensation considered to be permanent?
when it lasts longer than 6 months
What does “altered sensation” refer to?
- loss of sensation
- tingling
- abnormal sensation
- painful sensation
What is the effective dose of CBCTs for small fields of views used in dental imaging ?
9.3-51.2 uSv
What is the effective dose of a CBCT for a full arch in dental imaging ?
17.6-52.0 uSv
What is the reason for the range of effective doses for CBCTs used for dental imaging?
- many different machines
- tissue weighting factor (different tissues are exposed to the beam)
Why do younger people have an increased risk of developing neoplasia following exposure to radiation from a CBCT scan?
this is due to higher life expectancy
What are the radiographic signs of a close association between M3M and IAN canal on a CBCT ?
- narrowing of canal
- direct contact between nerve and root
- fully formed roots
- lingual course of nerve with/without perforation of the cortical plate
- intraroot position of the nerve
sandwiched between roots and thin lingual plate?
What are the strongest radiographic indicators on a CBCT scan for high risk of IANI ?
- narrowing of the canal
- direct contact
The coronal portion of the tooth is reduced with burs until the roots lie __mm below the alveolar bone
3mm
How is the crown moved in order to avoid mobilisation of the roots?
at a 45 degree angle
Why should retained roots following coronectomy not be root treated?
to reduce the risk of post-operative infection
What is the consequence of mobilisation of retained roots following a coronectomy?
- devitalizes the roots
- this leads to a foreign body response to the root
- thereby increasing the risk of post-operative pain and infection
What group of patients have been found to have the greatest risk of a failed coronectomy ?
women with conical roots
What surgical approach minimised lingual nerve damage ?
incomplete sectioning of the crown with the bur
crown partially sectioned with the bur and then fractured off with a hand instrument
Why is root migration regarded as a complication of coronectomies?
although they can migrate away from the ID nerve
migration towards the surface can cause irritation which demands surgical removal
root exposure may occur following migration
Up to mm of migration can occur after 24 months of the coronectomy
4mm
Aside from a coronectomy, what other treatments have been suggested for the managment of impacted M3Ms?
- orthodontic disimpaction
- sagittal split osteotomy
What is the purpose of a sagittal split osteotomy?
to mobilise and relocate the nerve
Outline some surgical management techniques that may be employed to treat damaged nerves
- removal of scar tissue
- opposing transected nerve ends
- nerve grafts
- nerve decompression
- low level laser therapy
