[Orthodontic movements and the periodontium: how far to go? A review of the literature].

The aim of this paper was to describe, with the help of recent research informations, the possible interactions between orthodontics and periodontics. It is well-known that the periodontal structures of a tooth play an important role during its orthodontic movement; this should therefore be considered before, during and after any orthodontic treatment. The theoretical basis of the usual difficulties are explained, as well as their clinical consequences. The particular problem of orthodontic movements in dentitions with reduced periodontal support has been stressed. A synoptic table summarizes the diagnostic steps and the clinical approach with the recommendations which seem, at the present time, to allow the preservation of the periodontal structures during orthodontic movement. Finally, the problem of apical root resorption is addressed in a specific chapter.