FR3066906A1 - MODULAR AND FLEXIBLE PRODUCTION EQUIPMENT OF PROTHETIC TEETH AND / OR ORTHODONTIC GUTTERS COMPRISING A ROBOT HAS ARTICULATED ARM TYPE FIVE OR SIX AXES, WITH IMAGING POST - Google Patents

Abstract

Equipment for manufacturing (1) prosthetic teeth and / or orthodontic aligners, comprising: - a robot (2) with an articulated arm (3) with five or six degrees of freedom, said robot respectively five or six axes; a manufacturing station (4) adapted to perform computer-aided manufacturing (CAM), individually or in groups, of blanks, by machining from a predefined block of material and / or by additive manufacturing, at least one finishing station for the blanks manufactured by FAO to obtain the teeth and / or the gutters, the robot arm being configured either to carry the block of material during its machining in the manufacturing station, then the machined blank and / or the blank manufactured by additive manufacturing up to the finishing station, either to carry the machining tool (s) and the finishing tool (s) and finally the teeth and / or or the finished aligners. It can also be provided an imaging station.

Description

MODULAR AND FLEXIBLE MANUFACTURING EQUIPMENT FOR PROSTHETIC TEETH AND / OR ORTHODONTIC GUTTERS INCLUDING A FIVE OR SIX-AXIS ARTICULATED ARM ROBOT WITH IMAGING STATION

Technical area

The present invention relates to the field of manufacturing prosthetic teeth and orthodontic aligners.

It relates more particularly to manufacturing by machining from blocks of predefined material and / or by additive manufacturing, that is to say by adding material, these two manufacturing techniques being computer-aided (CAD / CAM).

The invention aims in particular to propose a compact and autonomous manufacturing equipment which integrates all of the manufacturing operations up to the finishing and delivery of ready-to-use dental prostheses for all types of prostheses (crowns , screeds, bridges, inlays / onlays, removable metal frames ...) and all types of dental material (ceramics, feldspar ceramics, vitroceramics, chromium-cobalt, titanium, zirconium oxide ...).

The invention also aims to provide compact and autonomous manufacturing equipment which integrates all manufacturing operations up to the finishing and delivery of ready-to-use orthodontic aligners for all types of orthodontic aligners.

State of the art

Currently, there are two techniques for designing and manufacturing prosthetic teeth that are computer-aided (CAD / CAM).

The first technique involves machining blocks of dental material, that is, by subtraction.

In the first step, the dental technician scans using a scanning system that transforms an item into digital data, such as a 3D scanner, the desired tooth surface using the jaw mold produced by the dentist.

This data is sent from the scanner to CAM software which transforms the digital data into a machining program. It should be noted that CAM software is largely restricted for small machines and very easy to use, that is to say, it is impossible to configure the cutting conditions.

A machine tool comprising one or more motors to allow 3, 4 or 5 axes of freedom which will lead to milling cutters by controlling the CAM tool path software according to roughing milling strategies.

In other words, the cutter (s) carried by the machine tool comes to machine, that is to say cut and sculpt the prosthesis in a block of selected material which is supported by a fixed support of the machine tool.

The diameter and the number of teeth of the tool used have an important influence and are responsible for the duration of the machining.

The first operations to reduce the machining time are carried out with compact tools, with a larger diameter and with a greater number of cutting edges. The result of this draft is a dental prosthesis with the raw silhouette and an extra thickness.

The rough parts / blanks removed from the machine tools can then undergo different finishing operations, in order to obtain the most aesthetic result possible.

These operations can be limited to polishing the surfaces of the prosthesis, with more loose burs and dimension diameters, typically greater than or equal to 1mm.

Usually, these strawberries make it possible to produce the complex shapes of the extra-back (upper part of the tooth) and the bottom of the intra-back (lower part of the tooth). This leads to the finished prosthesis faithful to the external and internal contours defined with a very good surface condition, in particular at the level of contact with the gum.

It is also possible to make a glaze by depositing a glaze on the prosthetic tooth which has been polished, the glaze being followed by a heat treatment in a baking oven. The frosting can be combined with a make-up making it possible to reproduce in particular shades of shade.

The number of machine tools suitable for the production of restorations / dental prostheses has long been limited to a few models. The advent of open CAD software has increased the number of commercially available machine tools.

The advantages of the CAM machining technique are essentially very high precision, and the possibility of shaping any type of dental material, in particular zirconia, ceramics and resins.

The second technique consists in making the blanks of the dentures by additive manufacturing, generally, 3D printing, instead of machining.

According to this technique, a rough prosthetic tooth is modeled by successive deposits of layers of material which follow trajectories controlled by CAM software.

Thus, the outline of one or more prosthetic teeth is built on a tray. A print head comprising several nozzles moves horizontally and selectively projects the material to construct each layer of the prosthetic part.

To make another layer, the plate descends from the value of the thickness of the next layer, then a new layer of material is deposited. There are as many cycles as the number of layers required to obtain the draft.

The manufacture of a tooth or a group of prosthetic teeth requires the construction of a support so that the walls do not collapse. These supports are made with a soluble material, which facilitates their removal, in a bath or by spraying with a liquid solution. The parts obtained are used as models for the lost wax foundry.

The prosthetic tooth blank obtained by additive manufacturing must also undergo finishing operations.

The advantages of additive manufacturing by CAM are essentially that it allows complete assemblies like metal frames.

Whatever CAM fabrication technique for prosthetic teeth, there are still a number of disadvantages.

In particular, the finishing stages are carried out manually or with specific units which therefore involve the removal of the prosthetic tooth blanks from the initial machining machine tools or from the additive manufacturing machines, and the positioning in the specific units. .

This discontinuity in the manufacturing process induces significant manufacturing times and costs with the risk of increasing losses of precision and quality of obtaining prostheses.

Many different machines with each of the technical specifications with in addition manual operations are necessary.

In addition, the need for specific units means that the space required is not compatible with the space available to dentists in their dental offices.

There is therefore a need to improve computer-aided manufacturing (CAM) of prosthetic teeth, in particular so that they are shorter, less costly and that they are implemented in more compact equipment.

The object of the invention is to meet this need at least in part.

Statement of the invention

To do this, the invention relates to equipment for manufacturing prosthetic teeth and / or orthodontic aligners, comprising:

- a robot with an articulated arm with five or six degrees of freedom, said robot, respectively, five or six axes;

- a manufacturing station, suitable for performing computer-aided manufacturing (CAM), individually or in groups, of prosthetic teeth and / or orthodontic aligners, by machining from a predefined block of material and / or by additive manufacturing,

- at least one finishing station for blanks manufactured by FAO to obtain prosthetic teeth and / or orthodontic aligners, the robot arm being configured either to carry the predefined block of material during its machining in the manufacturing station, then the machined blank and / or the blank manufactured by additive manufacturing up to the finishing station, either to carry the machining tool (s) and the finishing tool (s) and finally the prosthetic teeth and / or finished orthodontic aligners.

In summary, the invention essentially consists in defining a new CAM manufacturing equipment for prosthetic teeth, equipped with a single robot with articulated arm whose flexibility of movement makes it possible to bring and support the blocks of dental material on the post of machining then transferring the machined and / or manufactured blanks by additive manufacturing to stations dedicated in particular to finishing.

Thus, compared with the manufacturing of CAM prosthetic teeth according to the state of the art, the invention makes it possible to implement all of the operations from machining and / or additive manufacturing to delivery of the finished prostheses and cleaned, in one and the same manufacturing equipment, thanks to the flexibility of movement brought by the robot arm with five or six axes.

The equipment according to the invention is very compact and completely autonomous and automated, which makes it usable not only by manufacturers, but also by personnel not qualified for machining and / or additive manufacturing, such as technicians or even dentists and also industrialists.

The equipment according to the invention can be easily moved, for example by installing it on a chassis mounted on casters.

In addition, the equipment is very clean and not noisy. It can be installed in any room of a building, typically of width less than 90cm to allow the passage of a standard door on European territory.

Finally, it is easy to foresee a connection of the equipment to a standard non-professional electrical network, such as a 220 V single phase 16 A supply.

The equipment according to the invention is a very flexible machine, which makes it possible to add or remove modules / zones for specific applications according to specifications and customer requests, such as for example:

- a module or work area in machining, with or without automatic tool change of cutting tools (milling cutters, grinding wheels, abrasive, etc.).

- a module or work area in polishing,

- a module or work area for coloring prosthetic teeth / aligners with temperature treatments (oven),

- a module or work area under control,

- a module or work area in additive manufacturing (3D printing),

- a module or work area for cleaning,

- a module or work area for automatic change of parts or elements to be produced.

- a module or storage area with packaging, if applicable .....

Thus, according to an advantageous embodiment, the finishing station is a station for polishing the preform machined and / or manufactured by additive manufacturing.

According to another advantageous embodiment, the equipment can include at least one additional treatment and / or control and / or storage station for the prosthetic teeth and / or finished orthodontic aligners, the robot arm also being configured to carry the teeth. prosthetics and / or orthodontic aligners, from the finishing station on any of the additional stations from the finishing station.

It can advantageously be an additional station for cleaning prosthetic teeth and / or orthodontic aligners.

It can also advantageously be an additional station for automatically loading a plurality of machining tools and / or finishing tools.

According to an advantageous embodiment, the equipment comprises an imaging station comprising one or more image sensors adapted to perform imaging of a predefined block of material, before or after its machining, and / or before or after its finishing, and if necessary before or after its passage in one of the additional stations.

According to this mode and a first variant, the robot arm is configured to carry the image sensor (s) and / or a camera for imaging the block of material and / or finished prosthetic teeth and / or orthodontic aligners which is (are) in a fixed position in the imaging station.

Alternatively, according to a second variant, the image sensor (s) and / or a camera for performing the imaging are in a fixed position in the imaging station, the robot arm being configured to carry the block of material and / or finished prosthetic teeth and / or finished orthodontic aligners.

With this imaging station, we can thus perform any type of dental imaging of all kinds of dental casting, teeth or any other form of dental block to be scanned. Depending on the applications and needs, we will choose the variant where the robot arm carries the imaging equipment, that is to say the imaging sensor (s), possibly integrated into a camera or carries the pieces of blocks of initial material and / or prosthetic teeth and / or finished orthodontic aligners.

The robot control-command unit can advantageously be provided for editing a control report by imaging any part in the rough, machined or finished state with all the traceability of the process followed beforehand within the 'equipment.

According to an advantageous alternative embodiment, the equipment further comprises a mass balancing system for a part carried by the robot arm and which supports one or more blocks of material and then the blank (s) and finally the prosthetic teeth and / or the finished orthodontic aligners.

The system may preferably include a balancing mass, the value of which is substantially equal to the mass of the worn part, the balancing mass being connected to the worn part by means of a flexible link wound around a pulley, so that when the robot arm moves, the balancing mass moves vertically to compensate for the mass of the moving part.

The invention also relates in another of its aspects, to a method for manufacturing prosthetic teeth and / or orthodontic aligners, implemented by equipment described above, comprising the following steps:

a / rotation of a machining tool of a fixed manufacturing station;

b / positioning of the robot arm bearing with a block of dental material to bring it into contact with the rotating machining tool;

c / movement of the robot arm along a trajectory determined by CAM software, so as to obtain one or more blanks of prosthetic teeth and / or orthodontic aligners;

d / rotation of a finishing tool, preferably polishing, of a fixed finishing station;

e / movement of the robot arm to bring the blank (s) from the manufacturing station to the finishing station and bring them into contact with the finishing tool;

f / movement of the robot arm along a trajectory determined by CAM software, so as to obtain prosthetic teeth and / or finished orthodontic aligners.

The invention also relates to a method for manufacturing prosthetic teeth and / or orthodontic aligners, implemented by equipment described above, comprising the following steps:

a ’/ start-up of an additive manufacturing device from dental material;

b ’/ additive manufacturing along a trajectory determined by CAM software in a manufacturing station, so as to obtain one or more prosthetic teeth and / or orthodontic aligners;

c ’/ displacement of the robot arm so as to take the blank (s) of prosthetic teeth and / or orthodontic aligners from the manufacturing station;

/ rotation of a finishing tool, preferably polishing, of a fixed finishing station;

e ’/ movement of the robot arm to bring the blank (s) from the manufacturing station to the finishing station and bring them into contact with the finishing tool;

f / movement of the robot arm along a trajectory determined by CAM software, so as to obtain prosthetic teeth and / or finished orthodontic aligners.

According to an advantageous variant, provision can be made for steps a / and b / to be carried out in conjunction with steps and b ’/ for the blank (s).

detailed description

Other advantages and characteristics of the invention will emerge more clearly on reading the detailed description of examples of implementation of the invention made by way of illustration and not limitation, with reference to the following figures among which:

FIG. 1 is a perspective view of a robot arm carrying a block of dental material in the form of a wafer, as it is installed in equipment according to the invention,

FIG. 2 shows the robot arm according to FIG. 1, provided with a system for balancing the mass of the block of dental material,

- Figures 3 and 4 are perspective photographic reproductions showing a prototype robot arm in a configuration for machining the preform of prosthetic teeth by a milling cutter mounted in a fixed station for machining equipment according to the invention;

- Figure 5 is a photographic reproduction showing the wafer of dental material carried by the robot arm of Figures 3 and 4 and in which have been preformed prosthetic teeth.

For the sake of clarity, the same reference numeral is used for FIGS. 1 to 5 to designate the same element of machining equipment according to the invention.

The prosthetic teeth machining equipment designated by the reference 1 firstly comprises a robot 2 with articulated arm 3, of the six-axis type.

The end of the robot arm 3 carries a support 4 of a block of dental material which is in the form of a wafer 5. This wafer 5 can be of any material known for the production of prosthetic teeth, such as wax, PMMA, zirconium, chromium-cobalt, titanium or other ...

In equipment, the robot arm 3 can move relative to an electrospindle 6.1, 6.2, 6.3 of a fixed manufacturing station. Thus, a cutter carried by one or the other of the electro-spindles 6.1 to 6.3 and rotating around its axis and the wafer 5 is brought into contact with the cutter. The movement of the robot arm along five or six axes allows the milling cutter to machine wafer 5 according to a predefined contour determined by CAM software, in order to obtain a roughing profile of one or more prosthetic teeth.

Provision can be made for machining by means of several cutters with a different profile and / or diameter, in particular depending on the contours of the desired blanks. Thus, it is possible to have several electro-pins 6.1 to 6.3, in parallel as shown in FIG. 1, each electro-pin carrying a different cutter.

The machining station can advantageously include a device for automatically changing the milling cutters. It may also include a device for automatically changing the wafers 5 of dental material to be machined in order to reload the equipment.

An advantageous embodiment is illustrated in FIG. 2. According to this embodiment, a balancing system 7 is provided for the mass of the wafer 5 and its support 4.

This balancing system 7 comprises a balancing mass 70 of value substantially equal to that of the wafer 5 and its support 4. This balancing mass 70 is connected by a cable 71 to the support 4 of the wafer 5, which passes through a pulley 72 maintained raised by a suitable structure 73. Thus, when the wafer 5 and its support 4 are moved by the arm 3 of the robot 2, their mass is compensated by the balancing mass 70 in vertical displacement by the intermediate of the cable 71 wound around the pulley 72.

Figure 2 also shows the arrangement of the robot arm 2 in a polishing finishing station within the same manufacturing equipment 1.

In this polishing station, provision can be made for installing one or more electrospindles 6 carrying finishing cutters. Thus, the finishing cutter or cutters can carry out a simple mechanical polishing of the blanks carried by the arm 3 of the robot 2 and coming from the manufacturing station.

The equipment can also include one or more additional control and / or cleaning stations for machined and finished parts and / or an imaging station, these stations being always accessible by the robot arm 3.

An imaging station can include one or more image sensors, which can be integrated into a camera, to perform imaging of any rough block and / or all machined and finished parts. In the end, once the prosthetic teeth are machined, finished, cleaned and checked by the dedicated stations, the robot arm comes to store in a dedicated storage station, the support 4 carrying the prosthetic teeth D.

The user can then come and collect these ready-to-use prosthetic teeth D.

For the positioning of the arm 3 of the robot 2 and therefore of the wafer 5 of dental material relative to the various milling cutters for roughing and finishing, it is possible to proceed either by visualization, or by probing, or by laser.

Figures 3 and 4 show an example of machining prosthetic teeth blanks in the same wafer 5 of dental material carried at the end of the robot arm 3, the milling cutters being arranged horizontally.

FIG. 5 shows an example of blanks of prosthetic teeth D machined in the wafer 5 carried at the end of arm 3 of robot 2.

Other variants and advantages of the invention can be achieved without departing from the scope of the invention.

All the examples illustrated can relate to the manufacture of orthodontic aligners jointly or in place of prosthetic teeth.

If in the examples illustrated, the block of material is in the form of a wafer, it is possible to envisage any type of block of dental material, such as ceramic blocks, vitroceramics and composite resins in particular marketed under the trade name of IPS. by the company Ivoclar Vivadent.

All types of dental materials can be used in equipment according to the invention, such as ceramics, vitroceramics, zirconium, wax, resins, chromium-cobalt alloy steels ...

In the illustrated embodiments, the machining of the blanks, their finishing and any other additional control or treatment are carried out with the block of dental material carried by the robot arm. We can also also consider keeping the block of dental material fixed in each manufacturing station, the robot arm then moving from station to station the block of dental material and bringing to its contact any tool for machining, finishing, cleaning and / or control required.

In place of the machining of the blanks by CAM or in a complementary manner, it is also possible to envisage installing an additive manufacturing station for the blanks of prosthetic teeth.

The invention is not limited to the examples which have just been described; one can in particular combine together characteristics of the examples illustrated within variants not illustrated.

Claims (13)

1. Equipment for manufacturing (1) prosthetic teeth and / or orthodontic aligners, comprising: - A robot (2) with articulated arm (3) with five or six degrees of freedom, said robot respectively five or six axes; - a manufacturing station (4) adapted to carry out computer-aided manufacturing (CAM), individually or in groups, of prosthetic teeth and / or orthodontic aligners, by machining from a predefined block of material and / or by additive manufacturing, - at least one finishing station for blanks manufactured by FAO to obtain prosthetic teeth and / or orthodontic aligners, the robot arm being configured either to carry the predefined block of material during its machining in the manufacturing station, then the machined blank and / or the blank manufactured by additive manufacturing up to the finishing station, either to carry the machining tool (s) and the finishing tool (s) and finally the prosthetic teeth and / or finished orthodontic aligners. 2. Manufacturing equipment (1) according to claim 1, the finishing station being a polishing station of the preform machined and / or manufactured by additive manufacturing. 3. Manufacturing equipment (1) according to claim 1 or 2, comprising at least one additional station for treatment and / or control and / or storage of prosthetic teeth and / or finished orthodontic aligners, the robot arm also being configured to carry the prosthetic teeth and / or orthodontic aligners from the finishing station to any of the additional stations from the finishing station. 4. Manufacturing equipment (1) according to claim 3, comprising an additional station for cleaning prosthetic teeth and / or orthodontic aligners. 5. Manufacturing equipment according to one of claims 3 or 4, comprising an additional station for automatic loading of a plurality of machining tools and / or finishing tools. 6. Manufacturing equipment according to one of the preceding claims, comprising an imaging station comprising one or more image sensors suitable for carrying out imaging of a predefined block of material, before or after its machining, and / or before or after its completion, and if necessary before or after its passage in one of the additional stations. 7. Manufacturing equipment according to claim 6, the robot arm being configured to carry the image sensor (s) and / or a camera for imaging the block of material and / or finished prosthetic teeth and / or finished orthodontic splints that are (are) in a fixed position in the imaging station. 8. Manufacturing equipment according to claim 6, the image sensor (s) and / or a camera for performing the imaging being in a fixed position in the imaging station, the robot arm being configured to carry the block of material. and / or finished prosthetic teeth and / or finished orthodontic splints. 9. Manufacturing equipment according to one of the preceding claims, further comprising a mass balancing system for a part carried by the robot arm and which supports one or more blocks of material and then the (the) blank ( s) and finally the prosthetic teeth and / or the finished orthodontic splints. 10. Manufacturing equipment according to claim 9, the system comprising a balancing mass whose value is substantially equal to the mass of the worn part, the balancing mass being connected to the worn part by means of a flexible link wrapped around a pulley, so that when the robot arm moves, the balancing mass moves vertically to compensate for the mass of the moving part. 11. Method for manufacturing prosthetic teeth and / or orthodontic aligners, implemented by equipment according to one of the preceding claims, comprising the following steps: a / rotation of a machining tool of a fixed manufacturing station; b / positioning of the robot arm bearing with a block of dental material to bring it into contact with the rotating machining tool; c / movement of the robot arm along a trajectory determined by CAM software, so as to obtain one or more blanks of prosthetic teeth and / or orthodontic aligners; d / rotation of a finishing tool, preferably polishing, of a fixed finishing station; e / movement of the robot arm to bring the blank (s) from the manufacturing station to the finishing station and bring them into contact with the finishing tool; f / movement of the robot arm along a trajectory determined by CAM software, so as to obtain prosthetic teeth and / or finished orthodontic aligners. 12. Method for manufacturing prosthetic teeth and / or orthodontic aligners, implemented by equipment according to one of claims 1 to 10, comprising the following steps: a ’/ start-up of an additive manufacturing device from dental material; b ’/ additive manufacturing along a trajectory determined by CAM software in a manufacturing station, so as to obtain one or more prosthetic teeth and / or orthodontic aligners; c ’/ displacement of the robot arm so as to take the blank (s) of prosthetic teeth and / or orthodontic aligners from the manufacturing station; / rotation of a finishing tool, preferably polishing, of a fixed finishing station; e ’/ movement of the robot arm to bring the blank (s) from the manufacturing station to the finishing station and bring them into contact with the finishing tool; f7 movement of the robot arm along a trajectory determined by CAM software, so as to obtain prosthetic teeth and / or finished orthodontic aligners. 13. The manufacturing method according to claim 12 in combination with claim 11, according to which steps a / and b / are carried out in conjunction with steps a ’/ and b’ / for the blank (s).