Comparison of linear measurements in cephalometric studies.

Five longitudinal cephalometric studies were evaluated with regard to discrepancies in their methodology. The roentgenographic enlargement was determined for each study separately. One linear cephalometric distance was then depicted graphically with and without correction for enlargement. This revealed that, besides other inaccuracies in the method, it was primarily the neglecting of radiographic enlargement that created considerable distortion of linear dimensions. Growth velocity curves were computed for three selected dimensions and graphically depicted. The determination of a growth spurt according to accepted definitions was impossible in these growth velocity curves. Problems arising in the determination of a growth spurt are discussed.