Orthodontic force/torque modeling and experiment of Kitchon root-controlled auxiliary archwire.

The incidence of oral malocclusion is increasing and is seriously damaging the oral health of human beings. The Kitchon root-controlled auxiliary archwire is an individualized orthodontic arch. It is used clinically for the treatment of tooth-lingual tilt/root-lip tilt phenomenon of the central incisors. However, the bending parameters of the Kitchon root-controlled auxiliary archwire used in different patients are based on the clinical experience of the dentists. Therefore, this orthodontic treatment has a high risk and unpredictability. In this paper, the loading performance and orthodontic process of Kitchon root-controlled auxiliary archwire are analyzed. And the prediction model of support resistance and correction torque are established. The bending parameters of the Kitchon root-controlled auxiliary archwire, as well as the effect of the bending parameters on the support resistance and the correction torque, are all quantified. And the prediction models for the support resistance and the correction torque are calculated separately. The correlation coefficients of calculated data and experimental data are ξ  > .97 and ξ  > .96, respectively; the correlation coefficients of simulated data and experimental data are ξ  > .96 and ξ  > .96, respectively. The accuracy and reliability of the established prediction models are verified. It provides an effective theoretical guide for dentists to safely and efficiently perform root-controlled rotation orthodontic treatment on patients' central incisors.