Articulator based on Theory of an equilateral triangle is:

Bonwill's theory articulators  • This articulator was designed by WGA Bonwill. • According to the Bonwill's theory of occlusion, the teeth move in relation to each other as guided by the condylar and the incisal guidances. • Bonwill's theory is also known as the Theory of equilateral triangle, according to which, the distance between the condyles is equal to the distance between the condyle and the midpoint of the mandibular incisors (incisal point).