Customized load cell for three-dimensional force-moment measurements in orthodontics

A customized load cell is developed to quantitatively evaluate the three-dimensional orthodontic actions applied during treatment. The force-torque sensor is part of a platform composed of 14 load cells, each one equipped with 6 strain gauges and interfaced with a tooth. The particular shape of the load cell allows detecting 6 mechanical actions independently that the tooth is subjected to. At the same time, a dedicated acquisition system is used to collect data simultaneously. The load cell is calibrated by applying known loads in a range between 0 N and 2 N. For each strain gauge´s output, good linearity (0.83 <; R² <; 0.99) and great repeatability (10^-4% <; STD <; 1.4%) are observed. Within this work, the load cell design, fabrication and characterization are described.