[A dental arch index related to tooth size and facial breadth]

Taking as its starting point the often postulated criticism of Pont's Index, the intent of the study was to develop a diagnostic procedure which took into consideration the objection that the Pont Index doesn't take the shape of the patient's skull into consideration. On the basis of the data obtained from the models and anthropological measurements of 50 adult subjects with fairly eugnathic dentition, the first step was to follow Pont and study which skull size exhibited the highest correlation to the posterior dental arch. Of all the relevant sizes the zygomatic arch width exhibited the highest correlation. Reference values for the posterior dental arch width, which were obtained with the help of regression analysis, which took into consideration both the total upper incisor width and zygomatic arch width as variables, were then established. These reference values were conclusively shown to have the best prognostic value. From this it can be concluded that a comprehensive orthodontic diagnosis should include an improved assessment of dental arch width.