The removal of third molar (wisdom) teeth is one of the most commonly performed

surgical procedures in the U.K. Figures published by researchers at the NHS Centre for Reviews and Dissemination at the University of York found that in 1994-95 there were over 96000 admissions for tooth removal. The majority of these were third molars, and the total cost of these procedures was estimated at approximately £50 million.

Although commonly practised, the procedure is not without significant risk. The report of a working party convened by the Faculty of Dental Surgery, The Royal College of

Surgeons of England, published in 1997, listed twenty-five headings of unfortunate outcomes or complications following surgery. The rate of complications after third molar surgery has been stated to be 11.8% in age groups 12-29 rising to 21.5% in age range 25-81. Altered sensation in the lip or tongue following sensory nerve damage is in the range 1-1.6% long term and 10-12%

temporary.

Little controversy surrounds the removal of third molars when they cause disease or severe symptoms, and widely disseminated criteria for their removal, such as one or more episodes of pericoronitis, were developed at a USA National Institutes of Health (NIH) development conference held in 1979.

There is widespread agreement within the dental profession that an important means of reducing the number of third molar surgery complications, such as altered sensation in the lip or tongue, is the careful selection of the teeth to be removed. Cost benefit analyses have shown that that prophylactic surgery (where there neither is nor ever has been disease associated with the third molar) is not in the patients best interest.

Put simply, the likelihood of an asymptomatic impacted third molar causing problems if left in situ is far lower than the likelihood of temporary or permanent problems as a result of complications if it is surgically removed. Despite this, a UK survey of 181 consultants found that 35.1% of 25001 third molars removed were disease free.

The locus classicus of the test for the standard of care required of a doctor or any other person professing some skill or competence, and what constitutes accepted practice, was the direction to the jury given by Mr Justice McNair in Bolam v Friern Hospital Management Committee ([1957] 1 WLR 582, 587), and until recently it has been clear that a dentist is not guilty of negligence if he acted;

...in accordance with a practice accepted as proper by a responsible body of medical men skilled in that particular area....a man is not negligent, if he is acting in accordance with such a practice merely because there is a body of opinion who would take a contrary view.

What then of accepted practice, such as the prophylactic removal of third molars, that can be shown not to be in the best interests of the patient? Certainly 35.1% of consultants continuing to remove symptom-free third molars could be argued to be accepted practice and it follows that a claim for medical negligence, following complications, relying on Bolam would likely fail.

The House of Lords ruling in Bolitho v City and Hackney Health Authority appears to remedy that situation:

It was found that a court was not bound to hold that a defendant doctor escaped liability for negligent treatment or diagnosis just because he led evidence from a number of medical experts who were genuinely of the opinion that his treatment or diagnosis accorded with sound medical practice. The court had to be satisfied that the exponents of the body of opinion relied on could demonstrate that such opinion had a logical basis.

In particular in cases involving, as they often did, the weighing of risks against benefits, the judge, before accepting a body of opinion as being responsible, reasonable or respectable, would need to be satisfied that, in forming their views, the experts had directed their minds to the question of comparative risks and benefits and had reached a defensible conclusion on the matter.

This was recently the basis and reasoning of my report prepared for Solicitors acting for a young lady who, following the removal of three third molars in 1997, suffered permanent lingual nerve damage. The two molars on the right side fell within the NIH guidelines for removal, the symptomless lower left third molar, in my opinion, did not. Unfortunately the removal of the left third molar caused the nerve damage.

Although no negligence was alleged to have occurred during the procedure, and written consent was obtained, it was argued that weighing the risks against benefit the procedure was not in the patient's best interests, i.e., the symptomless lower left third molar should have been left in situ. It was further claimed that because it had not been explained to the patient that the procedure was unnecessary, the consent obtained was not informed.

Expert opinion for the defendants, a major teaching-hospital Trust, argued that in 1997, and even in present day, a large proportion of consultants would carry out the procedure. This is unquestionably true, but in my opinion, based on Bolitho, this did not demonstrate that the expert had 'directed his mind to the question of comparative risks and benefits and had reached a defensible conclusion on the matter'.

The matter was settled on a favourable basis to the Claimant a week before trial.

G.M. Simon, Clinical Risk , AVMA Medical & Legal Journal (2000) 6, 28-29, January 2000