cephalogram

A cephalogram is a radiographic image of the head used in cephalometry to study craniofacial morphology. It is most commonly obtained as a lateral (side-view) radiograph, but frontal or posteroanterior projections are also used. The image records skeletal and soft-tissue relationships of the skull and facial profile.

Cephalometry relies on identifying specific cranial landmarks and performing angular and linear measurements to assess skeletal relationships (such as maxillary and mandibular positions relative to the cranial base) and dental alignment. The exam is used in treatment planning and monitoring, including orthodontic treatment, growth assessment, and surgical planning for jaw corrections. In modern practice, digital cephalometry allows tracing and analysis on computer software, including superimposition of images to evaluate changes over time.

Procedure is typically performed with a cephalostat to stabilize the head and an X-ray source. Exposure is brief and targeted to minimize radiation, and patient positioning is standardized to ensure comparability between images.

Limitations of cephalograms include the two-dimensional representation of three-dimensional anatomy, potential magnification and distortion, dependence on consistent head posture, and radiation exposure. Interpretations require trained clinicians, and measurement errors can occur due to landmark identification or technical factors.

History: The technique was developed in the early 20th century, with Broadbent’s lateral cephalometric radiograph becoming a standard method in orthodontics. Since then, the method has evolved with digital imaging and software, expanding the range of analyses and applications.