We appreciate the interest Dr Mew has taken in this controversial topic on the orthopedic effects of early treatment. Since he appears to have conducted a study with a larger number of twins, we were interested in the insight that his article could provide. In Dr Mew’s twin study, published in 2007 in the World Journal of Orthodontics , we found that there was no objective evaluation of skeletal differences, but only differences of facial appearance and dental features. In addition, the sample and the material of his study were too heterogeneous to support his statement that his trademarked functional appliance, used during early treatment, is more effective than late treatment with traditional fixed appliances.

Dr Mew’s statement that “fixed appliances are quite powerful and to some extent put the teeth and supporting bones into a ‘straitjacket’” is unfounded. It is well known that fixed appliances alone cannot affect the growth of the maxilla or the mandible.

Our objective with this case study was to report on the long-term skeletal and dental evaluations of a pair of twins with and without early intervention. It was striking that the reversed occlusion with 1-phase treatment mechanics for the Class III malocclusion had no impact on jaw growth. That means that the early treatment had not necessarily changed the size of the jaws. Therefore, the application of fixed appliances in the second phase must not be the principal reason why both twins achieved almost identical dentofacial features.

We understand that this is still a topic of contention, with many holding the belief that the facial skeleton is more easily influenced in early treatment and that those skeletal changes last forever. Unfortunately, the evidence seems to support the contrary, and this case study illustrates with images what numbers and angles often cannot portray.