[What is beauty?].

The face is a most important part of our features because of the importance it plays in communication. This paper looks at a means of defining what is normal and also what is beautiful. The face is a three-dimensional object and therefore needs to be measured in three dimensions. This paper describes an optical surface scanning system which has been used to analyze the faces of 40 normal patients with a Class I occlusion and also the faces of 30 models from the No. 1 Agency in London. The scans of each group has been separated into males and females, and the faces averaged to give an average normal male face and an average normal female face, an average model male face and an average model female face. These faces have then been compared by a special registration programme which enables the observer to compare the faces in three dimensions and record the amount of difference between them. The value of the system in forensic science for the identification of profiles in photographs is also illustrated as is its use in the building up of the soft tissues over the skull. The importance of which parts of the face are genetically determined has also been looked at by special shape analysis programmes and these are described.