cephalography

Cephalography is a radiographic examination of the head used to image the craniofacial complex for diagnostic and planning purposes. In orthodontics and maxillofacial surgery, cephalograms provide a two-dimensional representation of skeletal and dental relationships to help assess growth, malocclusion, and treatment outcomes. Lateral cephalograms are the most common view; frontal or posteroanterior cephalograms may be obtained to evaluate symmetry and bilateral structures.

Technique involves positioning the patient in a natural head posture, aligning the cranial base with the X-ray beam, and exposing a radiograph on a receptor placed in front of or behind the head. Images are traced manually or digitized for cephalometric analysis, which yields angular and linear measurements that quantify cranial base length, maxillary and mandibular positions, dental inclinations, and vertical dimensions. Widely used measurement systems include sets of angular relationships such as SNA, SNB, and ANB, among others, to characterize jaw relationships.

Applications extend to diagnosis and treatment planning in orthodontics and orthognathic surgery, growth and development assessment, and research or forensic anthropology. Limitations include the two-dimensional nature of the image, potential distortion from magnification, landmark identification error, and radiation exposure, though doses are generally low.

Digital imaging and, more recently, cone-beam computed tomography provide three-dimensional alternatives. CBCT can be used to derive cephalometric data or to supplement traditional cephalometry, often improving accuracy for complex cases.