This document discusses several advances in diagnostic aids used in orthodontics including digital cephalometry, videocephalometry, digigraph, CT scan, MRI, 3D study models, and others. It provides details on cephalometric radiographs, hand wrist radiographs, cervical vertebrae maturation index, and study cast analysis which are important diagnostic tools. It also summarizes digital radiography and how videocephalometry works in two steps to capture patient movement. Overall, the document outlines various imaging technologies and analysis methods that provide orthodontists important diagnostic information.