Automatic virtual alignment of dental arches in orthodontics

A key task in orthodontic treatment planning is to align the teeth in a given lower and upper arch so as to establish an ideal occlusion (i.e., contact relationship), subject to certain dental constraints. A simulation- based approach is introduced to establish a near- optimal occlusion based on certain dental constraints that are defined using features on tooth surfaces (e.g., cusps, ridges, incisal edges etc.). The alignment process is modeled as the simulation of a hypothetical spring- mass system where masses representing teeth are connected and influenced by springs representing dental constraints. The set of constraints chosen is based on well- known guidelines to achieve normal occlusion and to detect the most common type of orthodontic errors. The design and implementation of such a simulation- based system are discussed and experimental results are provided to demonstrate the efficacy of the approach.