Repeatability of head posture recordings from lateral cephalometric radiographs.

The mechanisms that control facial growth are still not known. One method for studying these mechanisms is the careful analysis of subjects with normal and aberrant growth patterns using standardized lateral cephalometric radiographs. It has been shown in normal subjects that head posture is related to facial development and that changes in head posture are influenced by changes in nasal respiratory resistance (NRR). In the determination of these associations it is therefore important to assemble cephalometric data from lateral skull radiographs that have been standardized for position as well as for natural head posture. The study demonstrates that a reproducible head posture position exists that can be recorded with a method error of only a few degrees.