Longitudinal changes in the ANB angle and Wits appraisal: clinical implications.

The changes in the ANB angle and the Wits appraisal between the ages of 5 and 25 years were evaluated in twenty male and fifteen female subjects. All subjects had clinically acceptable occlusions, and none had undergone orthodontic therapy. Descriptive statistics were calculated, and analysis of variance was performed. The conclusions derived from this investigation are as follows: (1) No significant differences were observed in the changes between male and female subjects for either ANB or Wits between age 5 and adulthood. (2) The ANB angle changes significantly with age, while the Wits appraisal indicates that the relationship between points A and B does not change significantly with age. (3) Correlation coefficients showed that the ANB angle and the Wits appraisal are significantly correlated but the r-values are relatively low. These findings explain the discrepancies that are present in some cases between the measured values of the ANB angle and the clinical judgment of the orthodontist. For a more accurate diagnosis of the anteroposterior apical base relationship, both the ANB angle and Wits appraisal should be used.