Biomechanical analysis for the distalisation of the mandibular dentition with anterior alveolar bone loss based on the location of an applied force: A finite element study
Abstract
Introduction
The present study analysed the tooth movement patterns and stress distribution in patients presenting with anterior alveolar bone loss, associated with the use of force vectors applied from a mini-screw to distalise the mandibular dentition.
Methods
Mandibular anterior teeth characterised by alveolar bone loss (zero, one third, one half of the root length) were constructed from a cone-beam computed tomography image, and a mini-screw was inserted into the mandibular buccal shelf. A distalising force of 2 N was applied from the mini-screw to three different lengths of an anterior retraction hook: 2, 7, and 12 mm. The tooth displacement and von Mises stress distribution in the periodontal ligament (PDL) were calculated via a finite element analysis.
Results
In all the models, significant movement was found around the anterior segment, and the stress was primarily concentrated at the cervical margin and apical area of the lateral incisor and canine teeth. With absorption of the anterior alveolar bone, extrusive lingual inclination of the anterior teeth, intrusive distal tipping of the posterior teeth and stress concentration in the PDL increased. Long retraction hooks led to lingual root and intrusive crown movement of the incisors and reduced uncontrolled distal tipping movement of the posterior teeth but also increased the range and magnitude of stress in the PDL of the anterior teeth.
Conclusion
During the distalisation of the mandibular dentition associated with anterior alveolar bone horizontal resorption, different retraction hook heights may be selected to control the movement of the teeth. Special consideration should be given to stress in the PDL of the mandibular incisors.
© 2025 Jing Yang, Qianqian Zhang, Dehua Zheng, Fengchun Hou, published by Australian Society of Orthodontists Inc.
This work is licensed under the Creative Commons Attribution 4.0 License.