Sir, to rationalise and defend the foundations of our beliefs is part of everyday modern life and very much part of science. Indeed the entire rational scientific method is based on a willingness to review and correct errors, and to accept challenges to what is already known. Nearly a million people in Britain are treated with orthodontics every year without a clear understanding of what is causing the problem, meaning the treatment is not based on the cause. It is only through science that we have a chance of finding the truth, this is what makes it so valuable.

In an editorial last year (A black swan; BDJ 2009; 206: 393) I invited the orthodontic community to join a debate on the aetiology of malocclusion. The editorial elicited two responses.

The first was from Dr G. D. Singh (BDJ 2009; 207: 52–53) who felt that the suggestion that the length of the mandible is under tight genetic control was 'ostensibly erroneous' and considers it possible even in an adult to 'show a tendency for renewed mandibular growth', which I would agree with but feel that there is little evidence for. And the second by Dr G. McIntyre (Déjà vu; BDJ 2009; 207: 97) who failed to 'see the logic in Dr Mew's article that the universities should prove his theories right or wrong', I feel that the universities have a duty to follow scientific procedure and seek the truth.

Since then I have approached the British Orthodontic Society who have argued against the need to hold such a debate and the GDC who have declined to repeat the debate that they held on this very subject in 1936 or discuss the situation further.

I feel that these esteemed professional bodies have shown an aversion to openness and a dismissive reaction to my scepticism that is not scientific. By avoiding rational debate the profession are betraying more than the integrity of their discipline, they are devaluing the science that they claim to uphold. Everything must be open to challenge, and I repeat mine inviting the orthodontic profession to a debate to test the hypothesis that 'malocclusion is caused by the environment and modified by the genes'. Who will accept this challenge?