[Antoni Cieszynski, Polish physician, dentist, and surgeon, 1882-1941]
In dental radiography, an application of the geometric theorem stating that two triangles are equal if they share one complete side and have two equal angles. The theorem is applied in the bisecting angle technique to guide film placement and angulation of the central beam of the x-ray. The resulting image on the radiograph is the same length as the projected object.
SEE: bisecting angle technique