RCSEng FPM XLA (2023) Flashcards
Why is planning for the FPM of poor prognosis so critical?
Enforced extraction of poor prognosis FPMs can cause disruption to the functional occlusion and impact on successful eruption of the SPM, particularly in terms of spontaneous space closure and
final SPM position
What is the goal of interceptive FPM extraction?
To achieve successful eruption of the SPM (and TPM if present, to complete the molar dentition) and the second premolar teeth, with space closure, a lack of tooth tipping and no overeruption of the opposing molar unit.
If there is no acute tx phase, what may be done to allow specialist planning for poor prognosis FPMs?
Any compromised FPM to be restored or stabilised to allow for specialist input, and allowing planning for the optimal time of extraction
What should we look for radiographically if we are considering XLA of FPMs?
Radiographic evidence of a SPM within alveolar bone and early mineralisation of its bifurcation (8-10yrs)
Mesio-distal angulation of the SPM and presence of the TPM in terms of favourable SPM eruption
(Esp in lower arch, as upper is less of a concern)
If FPM are extracted before 8/later stages of SPM eruption, what can happen?
The SPM and second
premolar can drift into the extraction space, tip, rotate and produce spacing in the dental arch with poor occlusal contacts
Why is it challenging to plan tx of XLA of FPM when considering the presence of TPM?
TPM development is usually evident radiographically by 8 years of age, but it can demonstrate wide variation and be delayed significantly
Tx planning often needs
to be undertaken before the presence or absence of the TPM can be confirmed
If a TPM is present and FPM interceptive extraction is carried out at the optimal time, what should be expected?
The child will ultimately have two molars in each quadrant in good occlusion; and therefore, in these circumstances, it is much more acceptable to extract a compromised FPM with an uncertain prognosis.
Why is it worse prognosis to extract a FPM in a quadrant without a TPM?
Extraction of the FPM will potentially leave the child with only one molar unit in the affected quadrant, leading to a reduced posterior occlusion and possibly unopposed teeth, if TPM are present in the opposing quadrant.
If a FPM requires an extraction, do we carry out compensating extractions routinely?
When the enforced extraction of a lower FPM is required the compensating extraction of a sound upper FPM should not be routinely carried out unless there is a clear occlusal requirement or likelihood of the upper FPM being unopposed for a significant period of time.
If a FPM requires an extraction, do we carry out balancing extractions routinely?
Routine balancing extraction of a sound FPM to preserve a dental centreline is not recommended unless part of a comprehensive orthodontic treatment plan.
In the upper arch, what is the prognosis of a SPM achieving a favourable occlusal position?
An unerupted SPM will generally achieve a good occlusal position following extraction of the compromised FPM (Patel et al., 2017). The upper SPM can be expected to drift mesially into contact with the second premolar
When may more consideration be required when regarding extractionsof upper FPM?
Crowding in the upper arch with space required/ correction of a class II incisor relationship
Attempted temporisation of the compromised FPM until the SPM erupts should be considered
Placement of a palatal arch on the erupted SPMs to prevent their mesial movement and maintain the FPM space
The introduction of what has made the effects of space loss due to early extraction of the upper FPMs much less significant?
TADs and innovative fixed
anchorage techniques
These patients can be managed with fixed appliances
Which arch is more predictable in terms of outcome of tx in the extraction of FPM?
The upper arch
Lower arch= timing is more critical
There is evidence that what can improve the position of TPM in both the upper & lower jaws?
Extraction of FPM, further supporting removal in those cases with an uncertain prognosis.
When might this guidance (RCSEng 2023) not be used?
The SPM is erupted – if it is, there is no advantage to an interceptive approach because a SPM in occlusion will not migrate mesially
Access to a recent DPT to assess SPM development and position, and the presence or absence of
TPMs is not available; or
There are acute symptoms such as pain, swelling or infection and the affected compromised FPM
or FPMs cannot be temporised.
What should be considered when tx planning extractions of FPMs?
The immediate clinical symptoms related to the compromised FPM
An accurate diagnosis of the prognosis of the affected teeth
The capacity of the patient to receive complex dental care
The availability of services – the location, availability and financial burden in seeking services
should be assessed;
The overall occlusion or malocclusion
The aspirations and values of the child and parent relating to dental care and the burden of future
