[Basic geometrical principles of profile harmony as an aid in planning and simulating maxillofacial surgery].

Dividing the facial profile into three sectors according to the principle of the golden section with one circle around the auditory meatus as the center provides a basis for a harmonic profile. An additional important factor for the general harmony of the profile is the nose. Based on a great number of measurements, computer programs allow preoperative profile simulations and the assessment of surgical feasibility. As numbers and the resulting numerical relationships play a fundamental role in the classification of the human body, it is possible to express beauty in terms of geometry. It is, however, only at certain definite numerical relationships of these three facial sectors to each other that a harmonic profile of the human head is produced. The resulting constructive ideals of beauty provide aids and guidelines in plastic surgery.