Patent GB-212241-A (GB)
Title: Apparatus for the intra buccal recording and transposition of the individual physiological movement of the teeth upon an articulator, without measurement
IPC: A61C11/02
Filed: 1924-02-21
Abstract: 212,241. Darcissac, M. P. Feb. 27, 1923, [Convention date]. Teeth, artificial; teeth, regulating.-Apparatus for use in setting up complete or partial sets of teeth or bridges, or for making straightening pieces, comprises pairs of plates held in position on the upper and lower jaws respectively, the upper plates being formed with projections which press into plastic material carried by the lower plates so that the natural movements of the jaws in biting are recorded in the plastic material which afterwards hardens. The plates are then transferred to models of the jaws mounted on an articulator so that the models, when moved by hand, are guided so as to reproduce the outward movements of the jaws. These movements are again recorded by coacting projections and plastic material carried by the articulator so that after removal of the original plates and during the setting up of the teeth the natural movements may be reproduced. The bite recorder for complete sets comprises upper plates 1 formed with projections 6, and lower plates 2 adapted to carry plastic material; these are secured, in coacting position, to vulcanite or other base plates mounted on models on an articulator. The base plates are transferred to the mouth, and frameworks of rods, Fig. 1, are detachably connected to the plates 1, 2 and are connected together by elastic bands 13 so as to hold the base plates firmly in position on the jaws. Biting movements of the jaws cause the projections 6 to make a record in softened impression wax placed on the plates 2. For partial sets and for straightening devices the bite recorder comprises, for the upper jaw, two parts 14, Fig. 4, formed with downward projections 17 and having projections 18 engaging slots in adjustably connected plates 21. Plastic materia.l 14<A> is carried by the parts 14 which are first adjusted on a model of the mouth and teeth so as to fit securely in the mouth. Corresponding parts for the lower jaw are formed with trays 20 for plastic material. The articulator consists of an upper part, Fig. 6, comprising two frames 26, 27, hinged together at 28 and carrying two trays 29 filled with softened plastic material, and a lower part, Fig. 7, comprising a plate 34 formed with upwardly and downwardly projecting nipples 35 and being situated, when the parts are assembled, in the space 33 between the trays 29 so that the. nipples form a record, in the plastic material in the trays, of the movements of the two jaws as controlled by the original records made in the bite recorder. The lower frame 27 carries guides 37<1> accommodating bolts 38 which may be moved to project into guides 37 in the upper frame so as to lock the hinge 28, or into guides 42 on the lower part of the, articulator so as to free the hinge 28 and lock the lower part to the frame 27. The record in the plastic material in the trays 29 is made with the hinge 28 locked, there being sufficient play between the plate 34 and the frames of the upper member to allow of the necessary movements. When the final record has thus been obtained the original records are removed and the teeth set up. By movement of the bolts 38 the articulator may be adapted for use as a plain hinge type or the hinge may be locked and the plaster records and the projections 35 employed as guides to give anatomical movements. The anchoring members may comprise parts 36, Fig. 6, and 41, Fig. 7, formed with grooved bars 44 sliding on dovetail projections 45, or may comprise tubes embedded in the plaster and sliding en rods on the articulator. An elastic handle or strap may be used with the articulator, or springs may be attached to bring the lower jaw upwards and rearwards into the position of occlusion. It is stated that the spacing between the plate 34 and the frame 26 during the movement of propulsion of the teeth shows the inclination of the condylian plate and enables teeth of suitable form to be chosen. The Specification as open to inspection under Sect. 91 (3) (a) states also that a ruler or graduated pointer may be provided to assist in the choice of the teeth. This subject-matter does not appear in the Specification as accepted.