title: Novel universal system for 3-dimensional orthodontic force-moment measurements and its clinical use.
abstract: BACKGROUND
  Orthodontic treatment is an important part of dental health care in Europe: the percentages of the population undergoing therapy vary from 10% to 55%. Therefore, quantifying effective orthodontic loads is a challenging topic with regard to the predictability of tooth movements and the reduction of traumatic side effects.
  
  
  METHODS
  A customized measuring platform was developed and used for detecting orthodontic forces in a range between 0.1 and 2 N. The system consists of 6 load cells, each equipped with 6 strain gauges. The tests were conducted on a 3-dimensional printed malocclused mouth model and on a plaster cast. Four types of superelastic ligation and 2 types of invisible aligners were tested to analyze, respectively, a malocclusion with a high maxillary canine, and the effects on the axial rotation of a maxillary central incisor with and without a divot in the invisible aligners.
  
  
  RESULTS
  Optimal treatment forces are exerted by low-friction wires, especially if they are partially engaged. Moreover, by reducing the treatment force, there is less necessity of anchoring to surrounding teeth, thus decreasing the side effects. The efficacy of using invisible aligners with a divot was validated.
  
  
  CONCLUSIONS
  This platform allowed measurement, at the radicular level, of the resultant forces of orthodontic treatments performed with different orthodontic appliances. In addition to customizing and calibrating the therapy for each patient, this platform could be used to develop new specific instruments able to exert lower treatment forces, thus preventing irreversible damages.
authors.affiliation: Postgraduate student, The Biorobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy. Electronic address: m.mencattelli@sssup.it.
authors.forename: Margherita
authors.initials: M
authors.lastname: Mencattelli
authors.affiliation: Postgraduate student, The Biorobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Donati
authors.affiliation: Private practice, Pisa, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Cultrone
authors.affiliation: Associate professor, The Biorobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Cesare
authors.initials: C
authors.lastname: Stefanini
mesh_terms: D001696:Biomechanical Phenomena; D003799:Dental Stress Analysis; D006801:Humans; D008953:Models, Anatomic; D016382:Orthodontic Appliance Design