Analysis and visualization of growth-related and treatment-induced craniofacial changes.

An analysis and visualization of craniofacial shape changes due to growth or orthodontic treatment is presented. The suggested method is based on an adapted Karhunen-Loève decomposition of time-discrete data based on landmarks in lateral X-rays of the skull. It allows for a reduction of the high-dimensional dynamic problem to a few spatial modes representing synchronous components of growth patterns with time-dependent mode coefficients. The growth-related shape changes as well as the orthodontic treatment effects are visualized by overdrawing the underlying shape changes. The results based on this technique give insight into the still controversially discussed question to which degree the craniofacial skeletal structures can be influenced by orthodontic appliances.