Dental and skeletal variation within the range of normal

The cephalometric radiographs of 79 patients with untreated ideal occlusions were evaluated. The means, standard deviations, modes and ranges for 10 of the most popular cephalometric measurements were recorded. While the means for many of the measurements are close to those reported by previous studies, the ranges vary widely. Correlation coefficients were used to identify and evaluate dental and skeletal adaptations associated with these variations. These closely resemble those proposed by Steiner, although showing a somewhat greater degree of variation. While profile evaluation was not a basis for inclusion in this study, a subjective evaluation revealed no patient having extremely poor or unattractive profiles. While it appears reasonable to use mean relationships as an initial goal of treatment in the growing patient, an understanding of limitations, natural adaptation and normal variation should provide additional help in diagnosing and treatment planning. This can be especially important in adult patients. Ranges recorded for individual skeletal relationships can also provide a rough guide in helping the clinician differentiate between those patients who can be treated orthodontically and those who might need supplementary surgical correction for skeletal deformities. As in any system of diagnosis, the information provided in this study must be adapted and modified on the basis of individual patient needs as it is integrated into a comprehensive diagnosis.