George Phillips introduced to the profession the central bearing point, (US Patent No. 1734398) along with his extra-oral tracer, the ”Graphic Recorder” (US Patent No. 1799528) in 1926. The construction of this articulator, also referred to by Phillips as the “Pantographic Articulator”, was based wholly on the oral records obtained with his “Graphic Recorder” and method.
This articulator, the “Student Model”, as well as the similar Model “C”, consists of a base with a lower cast holder and a floating arm with an upper cast holder connected to the base through a universal ball and sliding barrel joint. The upper arm rests on two adjustable horizontal planes by means of two vertical pins. The horizontal planes, when adjusted, represent the horizontal inclination of the glenoid fossae. Two vertical planes against which rest the horizontal pins control lateral movement of the floating arm. The upper arm is maintained parallel to the base by a rotary anterior guidance plate and vertical pin located behind the cast holders. The hinge mechanism of the articulator is anterior to and independent of the recorded eccentric movements. There is also an adjustment for movement in retrusion. The incisal guidance is controlled by an anterior rotating cam with various angles. There is a built-in mounting jig.
Phillips GP: Graphic reproduction of mandibular movements in full denture construction. J Am Dent Assoc, 1930;: 1489-1504;
The Phillips Articulators: Student and Model “C” and Graphic Recorder (Instruction Manual), The Dental Appliances Company, Boston , MA , 1932.
Dr. Edgar N. Starcke's articles in the Journal of Prosthodontics have more information on the history of articulators.