cephalometry

thumb|Craniometry Skull, 1902 Cephalometry is the study and measurement of the head, usually the human head, especially by medical imaging such as radiography. Craniometry, the measurement of the cranium (skull), is a large subset of cephalometry. Cephalometry also has a history in phrenology, which is the study of personality and character as well as physiognomy, which is the study of facial features. Cephalometry as applied in a comparative anatomy context informs biological anthropology. In clinical contexts such as dentistry and oral and maxillofacial surgery, cephalometric analysis helps in treatment and research; cephalometric landmarks guide surgeons in planning and operating.

== History == The history of cephalometry (cephalo- + -metry, "head measurement") can be traced through art, science, and anthropology. The origins of the important method of measuring has its origins in the Renaissance. Leonardo da Vinci is perhaps the most well known scientist and artist studying facial proportions during the Renaissance. Da Vinci along with others utilized grids to study the proportions of the face and make generalizations about them. Da Vinci looked for divine proportions in his quest to understand facial proportions. The divine proportion has since been found to exist in 20th centuries of facial proportions as they relate to esthetics. Beginning with Petrus Camper in the 18th century angles began to be employed in the measurement of facial form. Camper also began the practice of ethnographic grouping based on facial form. Anders Retzius defined the cephalic index and classified different shapes of the head. Brachycephalic refers to a small, rounded head. Dolichocephalic refers to a long head. Mesocephalic refers to a medium-sized head, typically between the brachycephalic and dolichocephalic sizes.