cephalometry

Cephalometry is the scientific measurement of the bones of the head, most commonly from radiographic images of the skull and face. It provides quantitative data on craniofacial morphology, growth, and treatment outcomes and is widely used in orthodontics, dentofacial surgery, and anthropological research. The standard modality is the lateral cephalometric radiograph, with posteroanterior views employed for certain assessments.

Cephalometric analysis relies on predefined anatomical landmarks, such as sella (S), nasion (N), point A (A), point B (B), porion (Po), orbitale (Or), pogonion (Pg), gnathion (Gn), and menton (Me). Reference planes commonly used include the sella–nasion line (S-N) and the Frankfort horizontal plane (Po-Or). From these, a range of angular and linear measurements are derived.

Classic analyses include Steiner’s SNA, SNB, and ANB angles to describe sagittal jaw relationships, along with Wits appraisal and various dental inclination and vertical measurements. Over time other methods—McNamara, Downs, Ricketts, and others—have provided alternative assessments. In recent years, three‑dimensional cephalometry using cone‑beam computed tomography enables volumetric evaluation and more precise landmark localization, though two‑dimensional radiographs remain standard due to lower dose and established reference data.

Limitations include landmark identification variability, projection and magnification errors, head positioning, growth-related changes, and population differences. Ethical considerations emphasize dose minimization, especially in pediatric patients, and the need for justified, standardized protocols. Cephalometry remains a foundational tool for diagnosis, treatment planning, and outcome assessment in orthodontics and craniofacial disciplines, increasingly complemented by 3D methods.