Modus operandi of Planas' appliance.

Planas' approach to the management of a distocclusion, as applied by Simoes, is analyzed physiologically by taking into account the Petrovic-Stutzmann's cybernetic vision of facial growth. This scientifically based theorization further strengthens the clinical validity of this orthodontic ideology and procedure. The clinician, the orthodontist, the functional orthopedist or the functional orthodontist are fundamentally dependent on their knowledge about biophysics, biochemistry and mainly physiology. It is important then that they be acquainted with fundamental concepts of basic sciences as applicable to the specialty. In planning the treatment of a malocclusion, it is necessary to select the appliance or the series of them for sequential use in the correction of a intermaxillary malrelation. It is also useful to be able to predict the response to each appliance. In this case it must be considered the input (appliance in the mouth) designed to produce either displacements of the teeth or other modifications within the dentofacial complex and the output (appliance effect). According to Petrovic and Stutzmann there are 6 tissue level growth categories. Previous investigations using Frankel appliance, LSU Activator, Bionator, Chin Cup and Begg techniques, have shown that when going from the growing category number 1 to number 6 it becomes easier to stimulate the growth rate and amount of the condylar cartilage and of the posterior border of the ramus and it becomes more difficult to restrain their growth rate and amount. In other words we have also to test clinically the effectiveness of the Planas Appliance by taking into account the inter-individual variation in the tissue level responsiveness to it. (Fig. 1-4).(ABSTRACT TRUNCATED AT 250 WORDS)