Patent GB-1244298-A (GB)
Title: Articulator
Inventor: SCHREINEMAKERS JOSEPHUS
IPC: A61C11/02
Filed: 1970-04-21
Abstract: 1,244,298. Articulator. J. SCHREINEMAKERS. 21 April, 1970 [22 April, 1969], No. 19058/70. Heading A5R. An articulator comprises a horizontal base member 1 which supports at its rear end two vertical side members 3, each provided with a slot 4 which is open at the rear end and upwardly inclined in the rearward direction at an angle of about 6‹ to the horizontal, a pin 6 connected to an upper arm 5 being rotatably and slidably received in said slots, a forwardly directed pressure being exerted on said pin by a spring 7, while the upper arm carries a support rod 9 which rests with its lower end on the base member when the upper arm is in its approximately horizontal rest position. In one embodiment the articulator also comprises a crescent shaped orientation plate 12 with a V- shaped notch (13) in its front edge and a needle fitting in sleeve 14 and hole 15 thus providing two reference points lying in the medial plane of the articulator. The orientation plate is also provided with perforations (16) through which wax may flow to give good connection when the lower bite plate is attached. A rod 17 connects the orientation plate 12 with a permanently magnetic fastener 18 which is attachable to the ferro-magnetic upper arm. The permanently magnetic fastener consists of a case (19) which is open at the side of the upper arm 5 and which is made of ferromagnetic material. A permanent magnet (20) is received in the case (19) which comprises two outwardly extending tabs (23) which are adapted to rest against the lower surface of the upper arm and provided with holes (24) which engage the pins 22. In use the wax rim of the lower bite plate is attached by means of wax to the lower surface of the orientation plate so that the centre of the front side of the lower bite plate is aligned with the V-notch (13) while the retromolar pads of the bite plate ar equidistant from the needle in hole 15. In this position it is certain that the medial plane of the lower bite plate corresponds to the medial plane of the articulator. Plaster of Paris is applied between the lower surface of the lower bite plate and the base member while the upper arm 5 is in its approximately horizontal rest position. Subsequently the orientation plate is removed from the upper arm and the upper bite plate is placed in the correct position on the lower bite plate where upon Plaster of Paris is applied between the upper surface of the bite plate and the upper arm. Preferably the orientation plate is upwardly inclined in the rearward direction at an angle of about 2‹ to the horizontal when the upper arm is in its rest position. In one modification, centring devices (25) for the lower and upper bite plates may be removably connected to the base member and the underside of the upper arm respectively. In this manner it is possible to attach the lower bite plate by means of Plaster of Paris to the lower centring device instead of the base member. In a similar manner the upper bite plate may be attached by means of Plaster of Paris to the upper centring device instead of the upper arm. Thus the plates may be removed from the articulator together with their centring devices while they may be remounted in the articulator again in their correct positions by means of the centring devices.