Letters From Our Readers

Re: Hsieh TJ, et al. Assessment of Orthodontic Treatment Outcomes: Early Treatment vs Late Treatment. Angle Orthod. 2005;75:162–170.

It is a delicate matter to criticize the work of sincere clinicians especially when one has strong views on a subject oneself. I am sure the finding by Hsieh and his colleagues that early treatment resulted in “prolonged treatment time, worse clinical assessment and higher rate of premature termination” was correct for their sample. However retrospective surveys are always at risk of unconscious selection and I was left wondering why 88 children were treated “early” and 322 were treated “late”. This infers that the clinicians might have been more familiar with late treatment or were they treating more obvious (and perhaps more severe) malocclusions earlier? There was no explanation for this and not everyone would agree with them that ten and a half equates with “early treatment” indeed I myself think that it is too late to achieve much skeletal change after eight. Treatment carried out during the deciduous changeover is always fraught with difficulties and this alone could account for the difference.

I was slightly nonplussed by the opening statement “early treatment is most frequently based on empirical judgment rather than evidence” and hope that this does not apply to me but it does infer that the authors have strong feelings on this issue. This might explain why their observation “the extraction rate was always much lower in the early treatment group” did not find its way into the conclusions although many would consider this the most significant finding of the paper.

Yours Faithfully,

John Mew