Prediction of optimal bending angles of a running loop to achieve bodily protraction of a molar using the finite element method
Document Type
Article
Publication Title
Korean Journal of Orthodontics
Abstract
Objective: The purpose of this study was to predict the optimal bending angles of a running loop for bodily protraction of the mandibular first molars and to clarify the mechanics of molar tipping and rotation. Methods: A three-dimensional finite element model was developed for predicting tooth movement, and a mechanical model based on the beam theory was constructed for clarifying force systems. Results: When a running loop without bends was used, the molar tipped mesially by 9.6° and rotated counterclockwise by 5.4°. These angles were almost similar to those predicted by the beam theory. When the amount of tip-back and toe-in angles were 11.5° and 9.9°, respectively, bodily movement of the molar was achieved. When the bend angles were increased to 14.2° and 18.7°, the molar tipped distally by 4.9° and rotated clockwise by 1.5°. Conclusions: Bodily movement of a mandibular first molar was achieved during protraction by controlling the tip-back and toe-in angles with the use of a running loop. The beam theory was effective for understanding the mechanics of molar tipping and rotation, as well as for predicting the optimal bending angles.
First Page
3
Last Page
10
DOI
10.4041/kjod.2018.48.1.3
Publication Date
1-1-2018
Recommended Citation
Ryu, Woon Kuk; Park, Jae Hyun; Tai, Kiyoshi; Kojima, Yukio; Lee, Youngjoo; and Chae, Jong Moon, "Prediction of optimal bending angles of a running loop to achieve bodily protraction of a molar using the finite element method" (2018). ASDOH Faculty Publications. 355.
https://scholarworks.atsu.edu/asdoh-faculty/355