Sir, the optimum management of mandibular third molars (MTM) that pose a risk of injury to the inferior dental nerve (IDN) is unresolved. Part of the problem is that the true risk of injury with different radiographic appearances has not been quantified in anything near a scientific approach that has credence. Nerve injury has become an accepted accompaniment to MTM removal but with modern approaches this perspective is increasingly open to challenge.

When a patient presents with an impacted MTM that obviously poses a risk to the IDN a number of surgical approaches have been proposed. One is the use of cone beam CT (CBCT) to gain 3D information on the relationship of the IDN canal to the tooth roots. An alternative option is to avoid encroaching on the nerve-root interface by performing a coronectomy. There is no consensus on how these options should be applied.

In the event of nerve injury the medico-legal response is to claim a failure of care if either one or both options have not been adopted. There are preliminary data1,2 to suggest that coronectomy all but eliminates the risk of IDN injury but as yet the evidence is tenuous and definitive studies are required to confirm the suggestion.

A survey was undertaken to establish the current pattern of care in this regard in the UK, Australia and New Zealand with 320 individuals completing a questionnaire: consultants (45%), associate specialists, specialty trainees, specialty dentist and primary care specialist practitioners (55%) who removed an average of 609 MTM teeth each year. Of these, 76% felt coronectomy had a role in MTM surgery with 66% willing to provide the procedure. However, most respondents did not believe coronectomy was an automatic choice for cases 'at risk' of IDN injury with it being offered only 40% of the time. Each individual carried out an average of ten coronectomies/year. CBCT was regarded by 89% as having a role (56% had access to CBCT). Respondents estimated an average of 26 CBCTs were prescribed/year for 'at risk' MTMs.

This indicates that CBCT and coronectomy are used selectively in current practice, that their role continues to divide opinion and that more evidence is required to clarify their optimal use. Clearly though, the routine use of CBCT or coronectomy is not the standard of care for the management of MTM deemed 'at risk' of IDN injury at the present time.

The authors would like to thank the societies and all the members of BAOMS, BAOS, ABAOMS and ANZAOMS for taking the time to kindly complete this survey.