[Biomechanical aspect of closing median diastema with a segmental arch].
Before orthodontic movement of the tooth it is necessary to analyze the anticipated system of forces. On an example of closing diastema between the upper central incisors with a segmental arch an analysis of the force and the moment which are manifested in the course of disactivation of apparatuses has been done. Prior to that biomechanical analysis enables planning and construction of a fixed orthodontic apparatuses so that the possibility of the unwanted movement of the teeth is avoided.