Cephalometric analysis
The cephalometric analysis is in a way dentistry , orthodontics and oral surgery is used.
With the help of a lateral x-ray (also a cephalometric x-ray , an X-ray image on which the entire skull is depicted in profile ), certain clearly defined cephalometric reference points are determined, and angles , distances and normal distances are determined by a so-called tracing . Using standards, particularly prominent features of a skull can be determined (e.g. a prominent chin ). Within research there are several schools of tracing . The most widely used is the HASUND drawing.
Important radiographic cephalometric reference points
Examples of key cephalometric reference points are:
- Sella turcica (the indentation of the pituitary gland )
- Nasion (the bridge of the nose)
- Pogonion (the most ventral point on the bony chin)
- Articular
- Menton
- Gonion
Important radiographic cephalometric reference values
There are a large number of routes and reference values that can only be given here as examples.
- SNPg angle: Expression of the sagittal positional relationship of the mandible or the prominent chin in relation to the base of the skull
- SNA angle: Expression of the sagittal positional relationship of the maxilla in relation to the skull base
On the basis of these values, indices and cumulative angles are also calculated, which are again compared with the average of the population using a reference norm . A special methodological feature is the so-called harmony box. Using the correlation calculation , clusters of cephalometric reference values were determined that show a common pattern . Using the multiple regression calculation , confidence intervals were then determined for each individual variable on the basis of the other. If the values are outside this interval they can be used as a discordant otherwise harmonious classified be.
Web links
Department of Orthodontics at the MHH (2004): Script for the seminar on the course in orthodontic treatment I & II for cephalometric analysis (modified from HASUND) ( Memento from February 25, 2005 in the Internet Archive )