[Periodontal reaction versus dental movement].

In orthodontics the relation between the force (natural or artificial) and the structures that must be modified or led towards a normal situation is in fact a complex equation would multiple aspects determined by the biological part. The orthodontic forces imply, both in action as in effect, all the elements of the dental system, meaning bones, teeth, periodontal tissue. On the other side, the structures of the dental system may help, limit ate, or even erase the action of the orthodontic forces. Our article brings into discussion the relation between the teeth' sustaining structures and their movements determined by the orthodontic forces both as a reaction to a therapeutical treatment and as their direct implication into the result and the stability of the orthodontic treatment, on a long-term.