Associations between the postural orientation of sella-nasion and skeletodental morphology.

The orientation of the sella-nasion line to true vertical in natural head posture is found to be correlated with some measures that describe internal craniofacial morphology.

Repeated measures analysis of geometrically constructed and directly determined cephalometric points.

Cephalometric landmarks were directly determined visually from bony anatomy on lateral cephalometric radiographs and compared with geometrically constructed cephalometric landmarks for repeated measures reliability of identification. Three groups of four orthodontists, grouped by level of experience, identified 18 landmarks on each of four cephalometric radiographs. This measurement procedure was repeated four times in 1-week intervals.