Three-dimensional modeling of an individualized functional masticatory system and bite force analysis with an orthodontic bite plate.

Abstract

Orthodontic tooth movement is affected by bite forces generated from the masticatory system. This study aims to study three-dimensional (3D) modeling of the individualized functional masticatory system and explore its application in orthodontics. An individualized masticatory system model containing the craniomaxilla, mandible, 4 pairs of primary masticatory muscles and complete dentition, including roots and precise dental crowns, was developed using 3D images from spiral computed tomography and digital casts. By registering global coordinates and using data transformation, individual movement data for mandibular opening, lateral excursion and protrusion were recorded with an Arcus Digma system and applied to this model to simulate the functional movements of the mandible. Using the finite element method, deformations and displacement of the masticatory muscles were simulated along with the mandibular movements. Under individualized muscle loading, the bite forces of the lower incisors with the orthodontic bite plate were analyzed. Individualized mandibular movements were simulated, and the performance of the masticatory muscles along with the mandibular movements was measured. The bite force generated on the lower incisors with different thicknesses and the orientations of the orthodontic bite plate were acquired. An individualized 3D masticatory system model was constructed using advanced 3D data processing software that integrated 3D images from different sources. Individualized mandibular movement and masticatory muscle performance were simulated using this model. The analysis of the bite force generated on the lower incisors with the orthodontic bite plate suggested that a thickness of 3mm may be appropriate for clinical use.