FR3079440A1 - PROTHETIC TOOTH MANUFACTURING EQUIPMENT COMPRISING A TYPE FIVE OR SIX AXIS ARTICULATED ARRAY ROBOT FOR COMPLETELY MANUFACTURING PROTHETIC TEETH DURING INSTALLATION, BASED ON DIGITAL DATA OF MODEL SCANS AND / OR NUMERICAL ORAL IMPRESSIONS - Google Patents

Abstract

The present invention relates to an equipment (1) for manufacturing prosthetic teeth complete of prosthetic teeth ready to pose from digital data of model scans and / or digital impressions with a single articulated arm robot whose the flexibility of displacement makes it possible to take the blocks of dental material and / or the models and / or the blanks and / or the machining or finishing tools, then to bring them from any post to another station, all the necessary stations being arranged on the periphery of the circular zone of movement of the robot arm.

Description

PROSTHETIC TEETH EQUIPMENT INCLUDING A FIVE OR SIX-AXIS ARTICULATED ARM ROBOT FOR FULLY MANUFACTURING READY-TO-FIT PROSTHETIC TEETH FROM DIGITAL MODEL AND / OR DIGITAL IMPRINT SCAN DATA

Technical area

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

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 ...).

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 or cutters 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 polished prosthetic tooth, 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.

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.

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.

To meet this need to improve computer-aided manufacturing (CAM) of prosthetic teeth, the applicant proposed in the French patent applications filed on May 30, 2017 under No. FR1754724 and on October 26, 2017 under No. FR1760094, 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 machining station then to transfer the machined blanks and / or manufactured by additive manufacturing on stations dedicated in particular to finishing.

The Applicant wished to go further in the development of such equipment, in order to offer an autonomous solution for the complete manufacture of prosthetic teeth ready for installation from digital data from model scans and / or digital oral impressions.

The object of the invention is therefore to propose such an autonomous solution.

Statement of the invention

To do this, the invention relates to equipment for manufacturing prosthetic teeth, comprising:

- a robot with an articulated arm with five or six degrees of freedom, said robot respectively five or six axes, the robot arm being adapted to move in any position within a circular zone of movement;

- a station for storing predefined blocks of material;

- a storage station for machining and / or finishing tools suitable for machining and / or finishing blocks;

- a station for storing models made from a predefined block of material;

- a model scanning station;

- a manufacturing station adapted to carry out computer-aided manufacturing (CAM), individually or in groups, of prosthetic teeth blanks, by machining from a model;

- at least one finishing station for blanks manufactured by FAO to obtain prosthetic teeth:

- a storage station for finished prosthetic teeth;

all the stations being arranged at the periphery of the circular zone of movement of the robot arm so that the latter can carry and move any predefined block, machining and / or finishing tool, model, tooth blank ( s) prosthetic (s), prosthetic tooth finished from one station to another, the stations being adapted to operate independently of each other.

Thus, the invention essentially consists in defining a new equipment for the complete production of prosthetic teeth ready for installation from digital data of scans of models and / or digital oral impressions, equipped with a single robot with articulated arm, the flexibility of movement makes it possible to remove the blocks of dental material and / or the models and / or the blanks and / or the machining or finishing tools, then to bring them from any station to another station, all the necessary stations being arranged at the periphery of the circular area of movement of the robot arm.

Thus, compared to 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 a single manufacturing equipment, thanks to the flexibility of movement provided by the robot arm with five or six axes.

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

According to an advantageous embodiment, the equipment comprises a piloting and CAM study station adapted to allow a user to configure the operation of the equipment from digital data of model scans produced in the digitization station. and / or oral digital fingerprints.

According to another advantageous embodiment, the equipment further comprises an additive manufacturing unit, arranged adjacent to the stations, outside the circular zone of movement of the robot arm, the additive manufacturing unit being adapted to produce individually or in groups, preforms of prosthetic teeth. The teeth blanks from the additive manufacturing unit towards the interior of the equipment frame can be produced either by the robot arm, or manually by an operator who comes to store the blanks in a storage station inside of the frame.

According to an advantageous variant embodiment, all the stations and the robot are housed in the same frame, preferably with restricted access from the outside.

The equipment advantageously comprises, as finishing stations, a station for finishing and / or polishing the preform machined and / or manufactured by additive manufacturing, a station for baking prosthetic teeth and a station for finishing the shades of the prosthetic teeth.

Preferably, the tool storage station includes automatic loading of a plurality of machining tools and / or finishing tools.

The invention also has a method of manufacturing prosthetic teeth, implemented by equipment described above, comprising the following steps:

a / input of digital scan data of models and / or digital fingerprints from the FAO pilot and study station;

b / movement of the robot arm so that it respectively takes one or more blocks of predefined material and / or models and one or more machining tools from their storage station and brings them into the machining station ;

c / machining in the machining station, so as to obtain one or more blanks of prosthetic teeth;

d / displacement of the robot arm so that it takes one or more finishing tools, preferably polishing, and that it brings it (them) in one or more finishing stations;

e / movement of the robot arm to bring the blank (s) from the manufacturing station to each of the finishing stations and put them in position to be finished with 1 ’(the) finishing tool (s);

f / movement of the robot arm so that it takes the finished prosthetic teeth to bring them to the storage station for the finished prosthetic teeth;

g / transfer of the finished prosthetic teeth to the outside of the equipment.

Advantageously, before step g /, a step of digital traceability of the finished prosthetic teeth is carried out in their storage station.

According to an advantageous variant, step e / comprises moving the robot arm to bring the finished tooth or teeth from the manufacturing station to the shade finishing station and to put them in position in order to receive the different shades.

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 given by way of illustration and not limitation, with reference to the single figure which represents in schematic view from above. prosthetic teeth manufacturing equipment comprising a robot with an articulated arm of the five or six axis type.

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

This equipment is intended to completely manufacture prosthetic teeth ready for installation from digital data from model scans and / or digital oral impressions.

The circular zone Z of movement of the robot arm 2 is shown diagrammatically in dotted lines in FIG. 1.

A set of stations is arranged in the same frame 3 at the periphery of the circular zone Z, as detailed below.

First of all, an FAO / CFAO control and study station 4, arranged outside the frame 3 allows a user to configure the autonomous operation of the equipment from digital model scan inputs and / or mouth prints.

Thus, a model scanning station 5 allows scanning of models which can be taken by the robot arm 2 from a storage station 6 provided for this purpose. As shown in FIG. 1, the storage station 6 can be arranged immediately next to the digitization station 5.

The robot arm 2 can move any machining and / or finishing tool from a dedicated storage station 7 and any block of dental material necessary for making blanks also from a dedicated storage station 8, for bring it to a machining station 9.

The block of dental material can be in the form of a wafer, which can be of any material known for producing prosthetic teeth, such as wax, PMMA, zirconium, chromium-cobalt, titanium or other...

The machining station 9 can be a five-axis machining station with one or more electro-spindles. Thus, a cutter carried by T electro-spindles in rotation about its axis makes it possible to machine a wafer of dental material which is brought into contact with the cutter. The machining is carried out according to a predefined contour determined by CAM software from the control station 4, 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-spindles in parallel, in the same station 9, each electro-spindle carrying a different cutter.

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

In place of the machining of the blanks by EAO or in a complementary manner, it is possible to envisage installing an additive manufacturing station 10 for the blanks of prosthetic teeth.

Thus, this station 10 allows the production of blanks for prostheses, bars, bridges, etc. according to a 3D printing technique, preferably by laser fusion, typically of materials of the chromium / cobalt or titanium type.

A finishing and polishing finishing station 11 makes it possible to finish the blanks. In this polishing station 11, provision may be made for installing one or more electro-spindles carrying finishing cutters. Thus, the finishing cutter or cutters can carry out a simple mechanical polishing of the blanks coming from the machining station 9 or from the 3D printing station 11.

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

Thus, a quality control station 12 can make it possible to control the quality of the finished blanks coming from the polishing station 11. This control can advantageously be carried out by a suitable scanner.

Also, to finalize the production of the prosthetic teeth, a cutting station 13 can be provided to allow the fasteners which still hold the finished prosthetic teeth to be cut to the remaining block of material.

Then, depending on the cosmetic aspect to be imparted to the prosthetic teeth, the robot arm can move them to a shade finishing station 14 in which one or more successive shades can be applied to the prosthetic teeth.

A cooking oven 15, in particular by microwave, then makes it possible to cook the shades on the prosthetic teeth.

In the end, once the prosthetic teeth are machined, finished, cleaned, checked and if necessary tinted by the various dedicated stations, the robot arm comes to store them in a storage station 16.

This storage station 16 can integrate a traceability system to be able to determine all the information desired for subsequent monitoring (date of manufacture, type of prosthetic teeth, identification by number assigned to the patient for whom the tooth or teeth are intended ...)

The prosthetic teeth ready to be installed in the mouth of a patient can then be extracted from this storage station 16.

All stations can operate independently of each other and the robot arm can therefore move any tool, block of material, model, blank, prosthetic tooth individually or in groups, inside the equipment. without having to wait for the end of a complete manufacturing cycle.

Thus, the equipment which has just been described makes it possible to carry out the complete manufacture of prosthetic teeth from digital scan data of models and / or oral impressions.

The equipment is compact, autonomous and allows great productivity because it allows to operate all stations simultaneously for different prosthetic teeth.

Its compact size allows it to be installed in any place, especially within a dental office. For example, its dimensions L * 1 can be of the order of 1 to 1.5 m by 0.9 m.

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

The blocks of dental material for making blanks can be in the form of a wafer, or any type of block of dental material, such as ceramic or glass-ceramic blocks, in particular sold under the trade name of IPS by Ivoclar Vivadent.

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

Furthermore, it is possible to envisage setting up one or more other manipulator arms to carry out the transfer of the blanks, teeth between the different stations, such as for example between the shade station and the baking oven.

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 (9)

1. Equipment for manufacturing (E) prosthetic teeth, comprising: - a robot (1) with articulated arm (2) with five or six degrees of freedom, said robot respectively five or six axes, the arm of the robot being adapted to move in any position within a circular area of displacement ; - a station for storing predefined blocks of material; - a storage station for machining and / or finishing tools suitable for machining and / or finishing blocks; - a station for storing models made from a predefined block of material; - a model scanning station; - a manufacturing station (4) adapted to carry out computer-aided manufacturing (CAM), individually or in groups, of prosthetic teeth blanks, by machining from a model; - at least one finishing station for blanks manufactured by FAO to obtain prosthetic teeth: - a storage station for finished prosthetic teeth; all the stations being arranged at the periphery of the circular zone of movement of the robot arm so that the latter can carry and move any predefined block, machining and / or finishing tool, model, tooth blank ( s) prosthetic (s), prosthetic tooth finished from one station to another, the stations being adapted to operate independently of each other. 2. Manufacturing equipment (E) according to claim 1, comprising a control station and CAM study adapted to allow a user to configure the operation of the equipment from digital data of model scans made in the scanning station and / or digital mouth prints. 3. Manufacturing equipment (E) according to claim 1 or 2, further comprising an additive manufacturing unit, arranged adjacent to the stations, outside the circular area of movement of the robot arm, the additive manufacturing unit being suitable for producing, individually or in groups, preforms for prosthetic teeth. 4. Manufacturing equipment (E) according to one of the preceding claims, all the stations and the robot being housed in the same frame (3), preferably with restricted access from the outside. 5. Manufacturing equipment (E) according to one of the preceding claims, comprising as finishing stations, a station for finishing and / or polishing the preform machined and / or manufactured by additive manufacturing, a cooking station prosthetic teeth and a shade finishing station for prosthetic teeth. 6. Manufacturing equipment (E) according to one of the preceding claims, the tool storage station comprising an automatic loading of a plurality of machining tools and / or finishing tools. 7. Method for manufacturing prosthetic teeth, implemented by equipment according to one of claims 2 to 6, comprising the following steps: a / input of digital scan data of models and / or digital fingerprints from the FAO pilot and study station; b / movement of the robot arm so that it respectively takes one or more blocks of predefined material and / or models and one or more machining tools from their storage station and brings them into the machining station ; c / machining in the machining station, so as to obtain one or more blanks of prosthetic teeth; d / displacement of the robot arm so that it takes one or more finishing tools, preferably polishing, and that it brings it (them) in one or more finishing stations; e / movement of the robot arm to bring the blank (s) from the manufacturing station to each of the finishing stations and put them in position to be finished with Γ (the) finishing tool (s); f / movement of the robot arm so that it takes the finished prosthetic teeth to bring them to the storage station for the finished prosthetic teeth; g / transfer of the finished prosthetic teeth to the outside of the equipment. 8. Method according to claim 7, according to which before step g /, a step of digital traceability of the finished prosthetic teeth is carried out in their storage station. 9. The method of claim 7 or 8, step e / comprising moving the robot arm to bring the finished tooth or teeth from the manufacturing station to the shade finishing station and to position them in order to receive different shades.