Growth of the mandible affects the outcome of orthodontic treatment in children. Traditionally, evaluation of mandibular growth uses 2D cephalometric analyses. While still used by orthodontists today, these 2D analyses are fraught with errors in measurement associated with interpreting 2D projections of 3D structures. Cone Beam Computer Tomography (CBCT) provides a means to study craniofacial structures in 3D. The objective of this study is to identify 3D topographical changes of mandible

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... the period of growth and development in orthodontic patients. Ten subjects with serial CBCT images were selected from the Bolton-Brush collection. The age of the subjects ranged from 8 to 14 years-old. Mandibular growth is evaluated using serial pairs of CBCT images which are segmented, superimposed using regional voxel-based mutual information, and quantitatively evaluated in AmiraXImage®. Surface topography changes over time in these 19 subjects are reported as follows: 56% of surface remodeling at a threshold of 0.5mm, median remodeling of 0.6mm, 0.8mm 0.6mm SD. Intra- and inter-rater ICC reliability for for surface generation (0.82 and 0.90, respectively) and superimpositions (0.94 and 0.93, respectively) demonstrate the reliability of the technique. The findings of this study support theories of bone remodeling reported in histological and radiographic studies of mandibular growth.