[0018] With reference to FIG. 1 , the method is applicable in general to the production of a plurality of elements intended to plug the damage caused in the teeth of mammals.

[0019] In order to implement the method, it is necessary in the first place to construct a model aimed at filling the loss or losses of substance from the dental organ or organs. This model may be produced in two ways, either directly in the mouth, mode A, or in the prosthesis laboratory, mode B, after taking an impression of the loss of substance by means of a conventional material (alginate, silicone or other). This impression will be processed in the prosthesis laboratory in such a way as to obtain a positive mould.

[0020] In the first mode A, the dentist, in operation 1 begins by removing with a drill or an excavator, the defective dental tissues in order to update and define a new volume 2 bordered by healthy tissues and having the shape of a tapered wall. Up to that point, this work requires the production of a cavity with or without counter-taper. With the method according to the invention, a counter-taper is banned.

[0021] The second mode B consists in taking an impression in the mouth of the dental preparation by using conventional impression compound and in a conventional and customary method in dentistry, then this impression is cast in plaster and, from this positive model, the first, already described, mode is rejoined to arrive at the new volume 2 . The practitioner ought also to take an antagonist impression with the preparation in order to be able manually to create the occlusal surface of the different models.

[0022] Based upon the new volume 2 , a model 3 is produced using opaque photo-hardening resin 10 in which is housed, prior to complete hardening, a manipulating rod 11 . After final hardening, the assembly is withdrawn, the rod 11 being immovably attached to the hardened opaque resin 10 , which resin is a model of the volume to be filled.

[0023] The assembly of rod 11 and resin model 10 is next positioned on the revolving platform 18 of a machine 4 for measuring in three dimensions by means of light wavefront analysis, for example an “OptoTOP” machine.

[0024] The “OptoTOP” machine uses a system of 3-D metrology in which the shots are recorded and analysed in three dimensions. The operation of the “OptoTOP” system is based on a principle of optical triangulation: topometry which uses a projection of structured and phase-offset white light.

[0025] For this purpose, a luminous rectangular pattern constructed from a plurality of luminous bands is projected on the model 10 of which the volume has to be measured. The luminous bands 16 are projected at an angle on the model and they match perfectly the shapes of the model. Machine 4 , via a CCD camera 17 positioned laterally in relation to the projector 15 , records quasi-simultaneously two images, the one conventional in two dimensions and the second which is that of the deformed bands, projected upon the model 10 to be measured. The projector 15 which generates the bands 16 is positioned at an angle to the camera 17 , the projector and the camera are mechanically and geometrically linked to the revolving platform which supports the model 18 by means of a frame 19 , in order to obtain a good triangulation. From a computer unit 21 , comparison software 12 next analyses the two images in order to calculate the volume observed by the camera, from a certain angle. The revolving platform 18 allows the exposure in succession of all the surfaces of the model to the light beams. A plurality of measurements are taken. These measurements are then converted into electronic files which describe the structure of the final volume of the model, either in the form of triangles (.stl format), or in the form of clouds of x y z points (ASCII format). These electronic files are then ready to be used by other software.

[0026] These files are then either compared with other files or manually modified by means of software for correcting or refreshing volume 20 , for example Polyworks software. The file produced from these modifications and characterising the definitive shape to be obtained is then either processed on the spot on a linked digitally-controlled machine 6 or it is sent via a computer network 5 to a computer unit 13 which controls this same digitally-controlled machine 6 , which is not linked, situated elsewhere in another geographical location. Once the electronic files described above have been received by this machine 6 , the machine is in a position to cut by means of drills 23 or other machine tools controlled by the machine and its software, a sized part 24 having at the end of the operation volume characteristics most closely approaching those of the model produced initially.

[0027] In this spirit, one of three known types of digitally-controlled machine can be used, for example: a digitally-controlled machine operating on three axes, four axes or five axes. When using a digitally-controlled machine on three axes, it will be necessary to proceed by reversal of the part to be machined. When using a digitally-controlled machine on four axes, in circular mode, the machining of the sized part to be machined 24 can be carried out either on the generator, or on the axis of rotation, or on the helix. When using a digitally-controlled machine on five axes, the combination of the five axes of the machine is used. The integrated software 22 in these different machines, for example the “Maquette Volume” software, can if required integrate additions of one or more square or rectangular fasteners 14 and remove traces of the rod 11 of the model.

[0028] The product of this machine then is a part 7 approaching the required volume with the addition of one or more fasteners 14 intended to physically maintain the definitive volume of the output part 24 of which it is the product. This fastener or these fasteners 14 are destroyed by the drill either by the dentist or by the prosthetist to obtain finally a part 8 which is the counterpart of the volume to be filled. This part 8 is then inserted by simple gluing into the initial volume 2 . The tooth 9 is thus reconstructed.

[0029] On the same principle, the method can be applied also to the production of prosthetic dental crowns produced from the second mode B described above. Starting with the positive model, firstly a 3-D recording is produced of the stump, which may or may not be coated with a thickness-compensating varnish. Secondly, after intervention by the dental prosthetist, and presentation of the antagonist moulds, a recording of the cap realised in hard or soft, opaque material is produced.

[0030] The 3-D recording software 12 already mentioned then produces, automatically or otherwise, the geometric link between the measurements of the stump and those of the model, created by the prosthetist.

[0031] At the end of this process, a virtual volume is obtained which defines the intrados and the extrados of the final cap or crown, to be machined.

[0032] For the bridges which are an assembly of caps and bridging pieces, the method uses again all the elements described above for the models and crowns, these volumes being linked.

[0033] The present invention has the advantage that a high degree of precision in the implanted elements is obtained, with the possibility of an effective neutrality of these elements, made out of diverse materials such as ceramics, marble, ordinary stone, precious stone, coloured material etc., with a high degree of compatibility between the contacts of the surfaces of the antagonist teeth and adjacent teeth.

[0034] It goes without saying that the invention has been described above by way of preferred example, which is indicative but not restrictive, and that it is possible to introduce any equivalence in its constituent elements without departing from the framework defined by the annexed claims.