Model Analysis is the first and foremost Adjunct to Cephalometrics. Measurements are performed on the models of each case to determine the Arch Form, Arch Width and Arch Depth. The Arch Form is assessed as Roman (IDEAL), Gothic or Truncated. The Arch Width and the Arch Depth is then measured. Each value is compared to IDEAL for an individual patient using the appropriate forms to compile the information. These are the first steps in the DIAGNOSIS of a case.