Dental recalls – a prickly subject

Porcupines – literally ‘spiny pigs’ - have a gestation period of about six months, which is completely irrelevant to dentistry but a useful introduction to the subject of recall intervals for dental patients.

I always understood that the traditional six month recall interval was the result of a decision by a civil servant, at the initiation of the National Health Service in 1948, that ‘no fee shall be payable for an examination of a patient for whom the same dentist was paid, or is entitled to be paid, a fee for an examination during the previous five complete calendar months.’ In other words, dentists could claim a fee every six months for an examination and as a consequence of that, six months became the default recall interval. There was as far as I am aware, no science behind that decision. It was purely administrative – and a rule rigidly applied by the clerks, and later the computers, at the Dental Estimates Board and its later configurations until the introduction of Units of Dental Activity in 2006.

In 2004, however, the National Institute for Health and Care Excellence (NICE) had issued guidelines which moved recall intervals away from the fixed six months to a risk-based approach, and stated that

‘the recommended interval between oral health reviews should be determined specifically for each patient and tailored to meet his or her needs, on the basis of an assessment of disease levels and risk of or from dental disease.’

With the introduction of the 2006 new contract, this risk based approach became a contractual requirement and this was reinforced in a 2022 Chief Dental Officer letter to GDPs. NICE also reviewed their guidance in 2020 in the light of the INTERVAL trial but made no changes to the recommendations.

The INTERVAL trial  report reviews the history of the six month recall interval, indicating that while initially the concept was to identify early lesions so that they could be restored, this has now moved on to identifying early lesions so that preventive strategies can be put into place.  Carried out in general practices (yippee! – research on the frontline!), the study concluded that

Over a 4-year period, we found no difference in oral health between patient participants allocated to a 6-month or a variable risk-based interval. Nor did we find a difference between the intervals of 24-month, 6-month and risk-based recall for the 30% of adults considered suitable to be at 24 months by their dentist. However, people greatly value and are willing to pay for frequent dental check-ups.

So, there’s no difference in oral health (caries and periodontal disease, at least – oral cancer was not considered) between those recalled at six months or those on risk-based recall intervals of one or two years. BUT patients like six month recalls. It’s been ingrained in the motivated patients’ psyche for three generations now.

What do dentists think? Ten years ago, a postal survey study showed that practitioners in West Sussex knew about the NICE guidelines, carried out the risk assessments but didn’t actually put them into practice, still using the six month recall pattern, believing that caries, periodontal disease and oral cancer may be missed with a less frequent recall intervals. The practitioners didn’t believe that access to NHS dentistry would be improved by lengthening recall intervals. A more recent interview based study of Welsh dentists showed a similar good understanding of risk assessment and recall intervals and were trying to put them into practice but found high risk patients resistant to three month recalls. The participants thought that the UDA system, perversely, encouraged the six-monthly recall of low-risk patients and were financially beneficial to their practices.

So, how often should patients attend the dentist? Longer risk assessed recall intervals of up to two years have no detriment to oral health but patients like six monthly recalls, are willing to pay for them and UDA’s encourage them.

There’s the paradox. The NHS would like the dentally healthy to attend less frequently so that space is freed up for the dentally unhealthy to be treated - or at least offered appointments.  Yet the payment system, the unloved Unit of Dental Activity, encourages the attendance of the (worried) well and positively discourages the treatment of the high needs, dentally unfit worried sick.

I wonder if what’s been left out of the limited research about recall intervals is that when dentistry works well, it is relational. How many times have we heard ‘I hate the dentist, but my dentist is wonderful?’ Wonderfulness comes out of relationship and relationship takes time to develop. From relationship comes trust, trust that what the dentist is saying about diet and flossing and attending regularly is actually quite important for those pearly whites with which we smile and speak and eat. If patients trust the source of the advice, they are more likely to put it into practice and if they do put it into practice, they are more likely to have healthy mouths.

Relationship will be built up and maintained four times faster meeting at six monthly intervals than every two years.

If we choose to meddle with the concept of six-monthly dental recalls, we need to do it in the same way that porcupines mate.

Very, very carefully.