Biomechanical analysis of asymmetric mesio-distal molar positions loaded by a symmetric cervical headgear

• Autorzy: Kizilova N. , Geramy A. , Romashov Y.

Identyfikatory

DOI

10.5277/ABB-00433-2015-02

• Języki publikacji: EN

Abstrakty

EN

Purpose: The plane 2d model and 3d finite element model of the headgear attached to two molars with different mesio-distal location are studied to show the asymmetric mechanical effects produced by symmetrically loaded headgear. In daily dental practice the asymmetrical location of molars is usually ignored. Methods: Six 3D finite element models of a symmetric cervical headgear were designed in SolidWorks 2011. The models showed symmetric molar position (model 1), 0.5 to 2 mm of anterior-posterior molar difference (models 2-5) and a significant asymmetry with 10 mm of difference in the locations (model 6). The head gear was loaded with 3N of force applied at the cervical headgear. The forces and moments produced on terminal molars are assessed. Results: It is shown the difference between the forces acting at the longer and shorter outer arms of the headgear increases with increase in the distance. The significant numeric difference in the forces has been found: from 0.0082 N (model 1) to 0.0324 N (model 5) and 0.146 N (model 6). These small forces may produce unplanned distal tipping and rotation of the molars around their vertical axes. The most important funding was found as a clockwise yaw moment in the system when is viewed superio-inferiorly. The yaw moment has been computed between -0.646 N•mm (model 1) and -1.945 N•mm (model 5). Conclusions: Therefore even small asymmetry in location of molars loaded by a symmetric cervical headgear will produce undesirable move-ment and rotation of the teeth that must be taken into account before applying the treatment.

Słowa kluczowe

EN

finite element method; force system; asymmetry; Yaw Moment; orthodontic tooth movement; headgear

PL

metoda elementów skończonych; FEM; system docisku; asymetria; ortodoncja

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Acta of Bioengineering and Biomechanics
• Rocznik: 2016
• Tom: Vol. 18, no. 4
• Strony: 97--106
• Opis fizyczny: Bibliogr. 25 poz., rys.,wykr.

Twórcy

autor

Kizilova N.

• Interdisciplinary center for mathematical and computational modelling, Warsaw University

autor

Geramy A.

• Tehran University of Medical Sciences, Dentistry Research Institute, Department of Orthodontics, Tehran, Iran

autor

Romashov Y.

• Kharkov National Polytechnical University, Faculty of Mechanical Engineering, Ukraine

Bibliografia

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