[Reactive changes in the periodontal microcirculation under orthodontic forces].

The influence of intrusive forces on the periodontal microcirculation exerted as conventional through brackets on the teeth is demonstrated with laser Doppler flowmetry. This noninvasive method shows that forces of 0.1 N on the human upper incisor cause a decrease of the periodontal perfusion of 20% which shall regain its initial level after 50-80 seconds. With an intrusive force of 0.5 N the perfusion decreases 42% within two to three seconds, which however shall not even regain its original level after ten minutes. Immobilisation of the teeth and infiltrative anaesthesia with vasoconstrictor were carried out in order to specify these measurements.