We were delighted to find that the American Journal of Orthodontics and Dentofacial Orthopedics has continued to publish on key issues in early orthodontic diagnosis, offering its readers articles that explore novel diagnostic criteria. An example is the recent article in the September issue (Baccetti T, Leonardi M, Giuntini V. Distally displaced premolars: a dental anomaly associated with palatally displaced canines. Am J Orthod Dentofacial Orthop 2010;138:318-22) investigating, in a retrospective study, the association between distally displaced premolars and palatally displaced canines (PDC). This well-designed study appears to be a continuation of a number of studies investigating the associations between dental anomalies and PDC. The main motivation for these articles, including this one, seems to be the clinical significance of early diagnosis of the likelihood of canine impaction.
The authors, however, did not explain exactly what clinical significance an early diagnosis of PDC could have. We doubt that an early diagnosis of PDC might have an important impact on clinical treatment strategy. To date, there is a lack of evidence that early diagnosis may influence subsequent planning of orthodontic treatment for the impacted canines. Successful treatment of tooth impaction seems to depend, rather, on the accurate positional diagnosis and the proper mechanotherapy.
One more question arises in that line of thought. Can we, as clinicians, be held accountable for x-ray exposure of our young patients merely to identify a remote “probability” of PDC, by prescribing radiographic exposure, when the results will have no influence on treatment planning? Generally, can we justify panoramic x-rays and lateral cephalograms at such an early age, as performed in the study by Baccetti et al (mean age, 9 years 7 months ± 1 year 3 months)? Council Directive 97/43/Euratom clearly enough states that radiographic exposure is justified only when the management of the patient depends on the information obtained from the radiography. Cephalometrics, for example, was shown not to be required for orthodontic treatment planning, since it has no influence on treatment decisions.
So, the answer to the question of whether the risk of more irradiation of a growing child is worth the diagnosis of PDC would depend on the possible “dramatic” consequences an impacted canine would have. We should not overestimate our specialty. Due to progress in medical technology (such as x-rays—Roentgen received the Nobel Prize for its discovery in 1901), it seems that the clinician is tempted to place a growing amount of trust in technology and modern computer-assisted facilities for data analysis, sometimes neglecting his natural diagnostic potential. X-rays should only supplement his clinical diagnosis—and only when it is really needed. Rumors have it that Konrad Roentgen once said, “Where there is light, there is also shadow.”