[Measurement of orthodontic appliance force using prototype sensors]

In introductory remarks the most important biomechanical principles, which are relevant for the research, and conditions which must be satisfied presented in intraoral measuring of orthodontic forces were pointed out. First the aim of the research was defined, and then the investigation of mechanical properties of acrylics as a material for orthodontic appliances were carried out. The type of strain gauges, bonds and measuring system configurations, as well as measuring amplifiers and recording instruments were discussed. Some of measuring sensors, their principles and applicability were discussed. The calibration apparatus was modified for the sensor developed, and the calibration results were analysed by means of statistical methods (linear regression). The behaviour of all used sensors were found to be linear, which enables their application and reduces the measuring results interpretation.