A study of the biomechanical characteristics of magnetic force systems used in orthodontics.

M.A. Papadopoulos
Hellenic Orthodontic Review 1999;2:89-97.

The aim of this paper was to study the orthodontic movement caused by magnetic forces in a laboratory-experimental environment. In order to study the orthodontic movement experimentally, a magnetic appliance was developed combined with conventional fixed orthodontic components. The appliance was tested for its effectiveness concerning orthodontic movement and it was also compared to conventional orthodontic force systems in an experimental model by means of a typodont. To study the tooth movements on the sagittal and vertical plane, standardized lateral radiographs were taken before and after force application. Occlusograms were used to study the tooth movements on the transverse plane.

According to the results of this study, permanent rare earth magnets offer a force system differing from conventional orthodontic force systems. Both attracting and repelling magnets produce their maximum force when brought into contact. When they are moved apart, the force decreases exponentially as opposed to conventional force systems, where force changes are proportionate.

Request for reprints: Dr. M.A. Papadopoulos, Lecturer, Department of Orthodontics, School of Dentistry, Aristotle University of Thessaloniki, GR-54006 Thessaloniki, Greece