The Sassouni analysis was developed in the late 1950’s by Dr. Viken Sassouni of the University of Pittsburgh. He measured 100 Caucasian children aged 7-15 years (51 females/49 males) of mainly Mediterranean origin. It was the first method to highlight vertical and horizontal relationships as well as the interaction between vertical and horizontal proportions. His analysis focused on skeletal proportions rather than absolute statistical values. They preferred the concept of proportionality over the concept of arithmetic normality. Simply by the drawing of lines and angles, visual assessment of the proportionality may be clearly seen. Sassouni showed that the horizontal anatomic planes – anterior cranial base plane, Frankfort plane, palatal plane, occlusal plane and mandibular plane – converge posteriorly at a single point O in well-proportioned faces. The angle of each plane shows the vertical proportionality of the face. The analysis, which is also popularized as Arcial analysis, uses the anterior and posterior arcs to study vertical facial proportions and to analyze the divergence of the horizontal planes.
In 1987, The Modified Sassouni + Analysis, a complete craniomandibular analysis, was first introduced by Dr. Richard Beistle of Buchanan, Michigan. In contrast with the previous Sassouni analysis, the authors determine absolute values to determine facial and skeletal growth patterns. It is useful in evaluating patients from a functional and neuromuscular perspective including TMJ and airway function. It is also useful in determining vertical proportion and growth potential of the patient. It can show incisor position in relation to opening and closing trajectory. It can also determine where to position the mandible for functional advancement.
Sources:
A Roentgenographic Cephalometric Analysis of Cephalo-facio-dental Relationships, Sassouni V 1955 AJO-DO V41 Issue 10 p735-764
Orthodontic Diagnostics: a Modified Sassouni + Cephalometric Analysis By – Jay W. Gerber, D.D.S., Richard T. Beistle, D.D.S. & Mr. Thomas S. Magill