Approccio ortodontico alle trasposizioni dentali

Objectives. The aim of this study is to report a case of upper canine/first premolar transposition treated according to the international guide lines. Teeth transposition is a rare eruption anomaly that involves permanent dentition, whose incidence is about 0.3-0.4%. It can be either complete or incomplete and in 90% of documented cases involves the canine transposed with the first premolar in the upper arch. This condition more commonly affects women on the left side and it is frequently associated to agenesis, lateral conoidal incisors, and retained teeth. Materials and methods. The aetiology is not clear: undoubtedly, there is a genetic composition often associated with a traumatic event. Diagnosis could be made at radiological level and the earlier the diagnosis, the lesser the risks related to the orthodontic treatment. However, the diagnosis is very often clinical and made late in permanent dentition. Results and conclusions. The treatment plan depends on the kind of transposition and on its severity. Data from the international literature suggest that the teeth should be left in their position if they are fully transposed, permanent dentition is complete, and there are no particular functional and esthetic needs. An earlier diagnosis allows the transposed elements to reach their normal position with no risks of root resorption or periodontal lesions.