Method for manufacturing a dental prosthesis and a shell mold adapted to carry out said method - Patents.com

Abstract

The present invention relates to a method for manufacturing a dental prosthesis, comprising the steps of digitally technically designing a dental prosthesis model from a patient's tooth replica model, creating a jaw part model consisting of the tooth replica model and the dental prosthesis model, manufacturing a jaw part (20) consisting of a positioning member based on said jaw part model, and positioning said jaw part (20) on a shell (32) of a shell mould (30) by interaction of the positioning member of said jaw part (20) with a complementary positioning member (36) arranged in said shell (32). The present invention also relates to a shell mould (30) for use in such a manufacturing method.

Description

[Technical field]

[0001] The present invention relates to a method for making a complete or partial (more commonly referred to as "Stellite") dental prosthesis, such as a removable dental prosthesis. The present invention also relates to a shell mold configured to carry out such a manufacturing method. [Background technology]

[0002] A dental prosthesis refers to an appliance that replaces at least some of the teeth that you are born with. A removable dental prosthesis is one that can be removed from the mouth, for example for daily maintenance or when sleeping. A "complete" dental prosthesis, also called a denture, refers to a prosthesis that replaces all of the teeth, whether maxillary or mandibular. "Partial" dental prostheses are used when only one tooth, or some but not all of the teeth, need to be replaced.

[0003] Thus, partial prostheses are traditionally constructed from a metal chassis (Stellite) used to support artificial teeth that are placed in the place of missing teeth. This metal chassis (usually containing chromium-cobalt-molybdenum) is very stiff and places a strain on both the remaining teeth and the mucosa (mainly the gingiva).

[0004] Dental prostheses may also be held in place in the oral cavity by at least one implant, which is a metal element that is fixed into the bone, sometimes via a screw, to replace the root of a tooth.

[0005] The production of dental prostheses requires the implementation of a highly precise protocol consisting of a series of steps, one of which is called flask moulding. This process involves imprinting a wax model of the prosthesis into a mould consisting of two separable parts called a flask. This model is made by hand by a prosthodontist, and the artificial teeth are placed on it one after the other.

[0006] Sometimes the imprint is made by pouring plaster into a flask. Once the plaster has hardened, the flask is heated to melt the wax and leave an imprint in the plaster. The plaster mold must be cooled before more material (usually resin) can be poured into the mold, which already has the artificial teeth in place.

[0007] In other cases, making the imprint is done by pouring a gel into a flask. Once the gel has solidified, the wax model can then be manually removed without a pyrolysis step. However, the artificial tooth must be separated from the wax model before it can be placed into the imprint formed by the gel. Furthermore, the artificial tooth is generally roasted to remove wax residues. The flask preparation process, particularly the setting of the plaster, baking the flask, cooling, and separation of the artificial teeth from the wax model, is time consuming and significantly retards the effective fabrication of the prosthesis. Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the present invention aims to at least partially overcome these drawbacks. The invention particularly aims to propose a manufacturing method that makes it possible to save time and increase the ease of manufacturing the dental prosthesis. [Means for solving the problem]

[0009] To this end, the invention relates according to a first aspect to a method for producing a dental prosthesis comprising: - digitally designing a dental prosthesis model produced from a patient's tooth replica model; creating a partial jaw model including a tooth replica model and a dental prosthesis model assembled to the tooth replica model; Digitally designing a model of a positioning member in a tooth replica model; manufacturing a jaw portion including a positioning member based on a jaw portion model including a tooth positioning member model; - manufacturing a tooth replica including a positioning member based on a tooth replica model including a positioning member model; positioning the jaw portion on the shell of the shell mold by interaction of a positioning member on the jaw portion with a complementary positioning member disposed within the shell; closing the shell mold; creating an imprint of the jaw portion by injecting material into a shell mold; Positioning at least one artificial tooth within the imprint of the jaw portion; positioning the dental replica on the shell of the shell mold by interaction of a positioning member of the dental replica with a complementary positioning member of the shell; placing a tooth replica within the imprint in which at least one artificial tooth will be placed; and casting a filling material into a remaining volume defined by the imprint, the at least one artificial tooth, and the tooth replica.

[0010] Such a manufacturing method for producing a dental prosthesis according to the invention therefore allows time savings by avoiding steps such as flaking and cooling the flask.

[0011] In fact, the wax prosthetic model is here replaced by a jaw part manufactured from a digitally designed model. In fact, the jaw portion is manufactured in a single piece.

[0012] Thus, since the jaw portion is one piece and is not necessarily reused in the remainder of the manufacturing process, there is no need to remove or sear the artificial teeth, and the artificial teeth can be placed directly after taking the imprint, eliminating the usual steps of searing and retrieving the artificial teeth.

[0013] Furthermore, the materials forming the jaw parts can then be recycled to allow for the manufacture of other dental prostheses or other products, as can the materials forming the tooth replicas, which can be manufactured in the same manner as the jaw parts.

[0014] In an exemplary embodiment, the steps of manufacturing the jaw portion and manufacturing the dental replica are performed simultaneously. This allows the manufacturing time of the prosthesis to be reduced.

[0015] The manufacturing method according to the invention therefore makes it possible to easily and quickly obtain a case-by-case made, i.e. custom made, dental prosthesis.

[0016] Furthermore, the use of a replica of the patient's teeth for the manufacture of the prosthesis, and more precisely during the process of pouring the filling material, makes it possible to obtain a more accurate match between the prosthesis and the environment in which it is intended to be inserted than with conventional manufacturing methods.

[0017] The presence of a positioning member on the tooth replica, and thereby on the jaw part, allows for a more accurate positioning of these two elements on the shell of the shell mould via the complementary positioning member, which therefore allows for a more accurate positioning of the tooth replica inside the imprint of the jaw part.

[0018] The positioning member may also be used to hold the jaw portion or the tooth replica in place on the shell of the shell mold, particularly when it interacts with a complementary positioning member, such as formed on the bottom of the tooth replica.

[0019] According to a preferred embodiment, the positioning member interacts with a complementary positioning member arranged on the shell according to a sliding link.

[0020] For example, the interaction between the positioning member and the complementary positioning member can form a dovetail assembly.

[0021] In this way, the movement of the jaw parts or the tooth replica relative to the shell is limited to a translational movement according to a single axis defined by the slide link, and it is therefore possible to adjust the position of the jaw parts or the tooth replica in translation according to an axis defined by at least one slide link.

[0022] According to another preferred embodiment, the positioning member includes a groove configured to interact with a complementary positioning member.

[0023] According to another preferred embodiment, the complementary positioning member includes a tab configured to interact with the positioning member.

[0024] The groove may have a polygonal cross-section and may be configured to interact with a complementary locating member to form a female portion of the dovetail assembly.

[0025] Similarly, the tab can have a cross-section configured to form the male portion of the dovetail assembly upon interaction with the positioning member. The tab can have, for example, a polygonal cross-section.

[0026] According to an option of interest, the complementary positioning members further comprise an axial stop. For example, this axial stop may allow for the stopping of translational movement of the jaw portion or the tooth replica when the positioning member interacts with a complementary positioning member according to the slide link. The axial stop thus forms a reference for positioning the jaw portion and / or the tooth replica relative to the shell. Indeed, it is possible to fix the jaw portion and / or the tooth replica in position by sliding it along an axis defined by the slide link to the axial stop.

[0027] Thus, the positioning of the jaw part on the shell is easily and quickly performed by the prosthodontist or any other practitioner by translating the jaw part until it stops. Moreover, by doing so, it is possible to position the tooth replica on the shell in the same way.

[0028] In an exemplary embodiment, the step of manufacturing the tooth replica is preceded by a step of translating the tooth replica model, in which undercut zones of the tooth replica model are digitally filled. These undercut zones are typically located at the junction between the tooth and the gums. Prior art methods required manual filling of these undercut zones with wax.

[0029] As a result, the fabrication process is designed to minimize or eliminate undercut zones in the tooth replica model.

[0030] This step is therefore carried out digitally, making it possible then to manufacture a tooth replica in which the "parallelized" zone is formed integrally with the tooth replica.

[0031] This is particularly advantageous during the process of making the imprint, in order to remove the jaw portion from the mould without damaging the imprint.

[0032] Furthermore, the undercut regions are filled according to a possibly digitally determined insertion axis, which corresponds to the direction in which the prosthesis is inserted into the patient's mouth, and which is generally determined by the doctor or by a piece of software.

[0033] According to certain exemplary embodiments, the step of positioning the imprint on the tooth replica is preceded by the step of positioning a Stellite chassis on the tooth replica. The Stellite chassis is particularly useful in the case of partial prostheses, which typically hold two separate parts of a prosthesis together. Advantageously, the Stellite chassis is firmly connected to the dental prosthesis after casting of the filling material.

[0034] Thus, getting the Stellite chassis into place is easy and quick for the practitioner, ensuring optimal adaptation to the environment in which it is intended to be deployed.

[0035] According to another exemplary embodiment, the method further comprises drilling supply channel openings in the imprint. This supply channel is then used to cast the filling material to create the dental prosthesis. In the example of interest, at least two channels are drilled to allow simultaneous casting of the filling material and evacuation of any air present in the imprint.

[0036] According to an exemplary embodiment, the step of manufacturing the jaw portion and / or the tooth replica is performed by additive manufacturing.

[0037] According to the present invention, "additive manufacturing" refers to a manufacturing method that adds material, most often computer-assisted, and is more commonly called "3D printing". Additive manufacturing techniques allow, for example, more precise production of jaw parts. Thus, there is no need for manual production of wax models.

[0038] Additionally, the precision of additive manufacturing may be able to eliminate the need for polishing steps, which are often time-consuming, costly, and can damage the part.

[0039] Thus, at least in certain cases, the dental prosthesis produced may be directly ready for use with such methods or may require only minimal post-processing steps, for example to obtain a polished mirror-like appearance on some surfaces of the dental prosthesis.

[0040] According to an exemplary embodiment, the process of manufacturing the jaw portion and / or the tooth replica is carried out in successive layers according to a method including successive application of material by jets onto a print support, the material being solidified by photopolymerization after each jet.

[0041] For example, the jaw portions can be made from monomers, polymers, or photopolymers. Preferably, the jaw portions are made from PA12 (Polyamide 12, also called Nylon 12).

[0042] Indeed, PA12 has the interesting ability to recycle the non-fused powder after carrying out the additive manufacturing method as described herein, thus making it possible to reuse this powder for making other prostheses or even other products.

[0043] According to another aspect, a shell mold for producing a dental prosthesis is also provided. In accordance with the present invention, the shell mold includes a complementary positioning member configured to interact with a positioning member of an insert positioned within the shell mold. Such a mould is therefore particularly adapted to carry out the method as described above.

[0044] In the context of the present invention, a "shell mold" refers to a mold formed by at least two parts that interact with each other, such that each part is referred to as a "shell."

[0045] The insert corresponds here to any part that allows to carry out at least some of the steps of imprinting, molding or overmolding to produce a dental prosthesis. For example, according to the invention, the insert can be a replica of a tooth or jaw part of a patient.

[0046] Such a shell mould therefore has similar advantages as those discussed above with respect to the method.

[0047] According to one embodiment, the complementary positioning member is configured to form a slide link with the positioning member of the insert.

[0048] In particular, the complementary positioning members may be configured to form, for example, a male portion of a dovetail assembly.

[0049] According to one embodiment, the complementary positioning member includes a tab configured to interact with the positioning member.

[0050] According to a complementary embodiment, the complementary positioning member includes an axial stop that prevents translational movement of the positioning member when it interacts with the complementary positioning member. In particular, the axial stop can be formed by protruding surfaces which protrude transversely to the longitudinal direction of the tab and act as guides for translational movement, e.g. perpendicularly on either side of the tab, so that the complementary positioning members have a T-shape. [Brief description of the drawings]

[0051] The invention, according to exemplary embodiments, will be better understood and its advantages will become more apparent on reading the following detailed description, given for informational purposes and in no way for limiting purposes, with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 is a diagram showing an example of a patient's tooth replica model according to an embodiment of the present invention. [Figure 2A] FIG. 2A is a frontal, high-angle view of an example patient tooth replica model of FIG. 1 with a positioning member. [Figure 2B] FIG. 2B is a rear view, substantially at a low angle, of the dental replica model of FIG. 2A. [Figure 3A] FIG. 3A illustrates an example partial jaw model from a high angle, as obtained from the example teeth replica of FIGS. 2A and 2B, in accordance with an embodiment of the present invention. [Figure 3B] FIG. 3B is a rear view, substantially at a low angle, of the exemplary jaw of FIG. 3A. [Figure 4]FIG. 4 is a diagram illustrating positioning of a jaw portion on a shell of a shell mold performed using the jaw portion model of FIGS. 3A and 3B, according to an exemplary embodiment of the present invention. [Diagram 5] FIG. 5 illustrates, in a perspective view, the step of closing the shell mold with the jaws positioned over one of the shells as shown in FIG. [Figure 6] FIG. 6 shows the imprint of the jaws made in the shell mould and the process of forming the supply channels. [Figure 7] FIG. 7 is a diagram showing a step of positioning an artificial tooth in the imprint of FIG. [Figure 8] FIG. 8 is a diagram illustrating the step of placing a tooth replica made from the tooth replica model of FIGS. 2A and 2B onto the shell of the shell mold of FIG. [Figure 9] 9 is a perspective view illustrating the step of closing the shell mold with a dental replica placed on one of the shells as shown in FIG. [Figure 10] FIG. 10 illustrates the process of pouring a filling material into the interior of a closed shell mold containing a tooth replica such as that shown in FIGS. [Figure 11] FIG. 11 illustrates a dental prosthesis obtained according to an exemplary embodiment of the present invention. [Figure 12] FIG. 12 is a schematic diagram illustrating a method for manufacturing a dental prosthesis according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] Identical elements shown in the previous drawings are identified by the same reference numbers. FIG. 1 shows a patient's tooth replica model (1). Such a model is obtained, for example, through a process of taking a digital technical imprint (not shown) performed via a table scanner on a plaster model or, preferably, via an intraoral scanner directly inside the patient's mouth.

[0053] The tooth replica model 1 therefore corresponds to a digital representation of a part of a patient's jaw, in this case the mandibular part, for which a dental prosthesis has to be produced.

[0054] This tooth replica model 1 is typically stored in an STL format file and viewed using computer-aided design software.

[0055] The tooth replica model 1 includes, for example, an "upper" portion that mainly forms the tooth portion, and a "lower" portion that mainly forms the gum portion. The tooth replica model 1 further comprises a posterior or lingual portion representing a concave inner surface. In the illustrated example, the tooth replica model 1 includes at least one missing tooth 3 at the top.

[0056] Furthermore, in the illustrated example, the tooth replica model 1 comprises at least one remaining tooth 5. The dental prosthesis to be produced is in this case a partial dental prosthesis.

[0057] Of course, the invention is not limited to this type of dental prosthesis, but also applies to other types of prostheses, for example complete dental prostheses, ie those in which the tooth replica model does not include the teeth 5.

[0058] 2A and 2B, the tooth replica model 1 also includes an anterior portion presenting a convex outer surface. The anterior portion is therefore opposed to the posterior portion, and the distance separating them forms the thickness of the tooth replica model 1. The tooth replica model 1 further comprises a lower surface 7 in the lower portion. This surface is adapted to be stably placed on a support once the tooth replica model 1 has been produced. The underside 7 of the lower part of the tooth replica model 1 defines, for example, a plane.

[0059] 2A and 2B also show a positioning member model 8 placed at the bottom of the tooth replica model 1. In particular, the positioning member model 8 is placed starting from the bottom surface 7 of the tooth replica model 1. In the illustrated example, the positioning member model 8 includes a groove 8a. The groove 8a is configured to form a slide link with a complementary member.

[0060] In fact, a groove 8a runs according to a longitudinal axis between the rear and the front part of the tooth replica model 1. The groove 8a has a trapezoidal cross section which here, by interaction with a complementary member, only allows movements according to the longitudinal axis of the groove 8a.

[0061] In the example shown in Fig. 2A and Fig. 2B, a groove 8a is hollowed out starting from the lower surface 7 of the tooth replica model 1. The groove 8a extends parallel to the plane defined by the lower surface 7 over at least a part of the thickness of the tooth replica model 1. For example, in Fig. 2B, the groove 8a extends from the rear to the front of the tooth replica model 1, i.e. over the entire thickness of the tooth replica model 1. In other words, the groove 8a penetrates completely through. In this exemplary embodiment, the positioning member model 8 also includes a fastener element or fastener 8b configured to stop the translational movement of the tooth replica model 1. According to an interesting option, the fastener is formed by the front part of the tooth replica model 1. In this embodiment, the fastener 8b includes a protrusion extending from the front part of the tooth replica model 1. The protrusion of the fastener 8b includes a flat surface perpendicular to the longitudinal axis of the groove 8a.

[0062] 3A and 3B show a partial jaw model 2 including the tooth replica model 1 shown in FIGS. 2A and 2B and a dental prosthesis model 4, shown hatched, assembled to the tooth replica model 1 by digital technical design.

[0063] The dental prosthesis model 4 is digitally designed based on the tooth replica model 1. For best adaptation, the profile and shape of the denture model are determined according to the tooth replica model 1. The profile of the dental prosthesis model 4 is also determined according to an insertion axis, i.e. a trajectory for inserting the dental prosthesis model in the patient's mouth by simulation. This insertion axis is determined, for example, by the denture fitter or by software.

[0064] Thus, the dental prosthesis model 4 typically includes at least one tooth and optionally a gingival portion according to the tooth replica model 1 to form a corrected, fully dentated jaw segment model 2 .

[0065] In the case of a partial dental prosthesis, the dental prosthesis model 4 may include a Stellite chassis model (not shown) configured to abut at least one remaining tooth 5 and / or mucosa, in particular the gingiva, and / or to hold together at least two separate parts of the dental prosthesis model.

[0066] It can be seen that the lower part of the jaw part model 2 corresponds completely to the lower part of the tooth replica model 1. In fact, only the hatched part shown on the jaw part model 2 differs from the tooth replica model 1. The jaw part model 2 therefore also comprises at its lower part a lower surface 7. The jaw part model 2 therefore also has a positioning member model 8 identical to the positioning member of the tooth replica model 1, here comprising a groove 8a and a catch 8b.

[0067] 4 illustrates the step of positioning jaw portion 20 on shell 32 of shell mold 30. Shell mold 30 includes two shells, here shell 32 and a complementary shell 34 configured to interact with shell 32 to close shell mold 30.

[0068] To this end, shell 32 and complementary shell 34 each include a notch 33a and a hook 33b, which is configured to interact with notch 33a to hold shell mold 30 closed. Of course, any other means for closing shell mold 30 is contemplated, such as a rubber band.

[0069] The shell 32 has a bottom 35. The bottom 35 here defines a flat surface. The flat surface formed by the bottom 35 is intended to receive the jaw portion 20 on its lower surface 7 side.

[0070] According to the illustrated embodiment, a casting hole 38 is disposed in the complementary shell 34 for filling the shell mold 30 with material to form an imprint of the insert. The material for forming the imprint is a hydrocolloid gel. Such a shell mold 30 may form, for example, a dental flask.

[0071] FIG. 4 also illustrates an exemplary embodiment of a jaw section 20 that is made from the jaw section model 2 shown in FIGS. 3A and 3B.

[0072] The jaw portion 20 is, for example, manufactured by additive manufacturing. For example, the jaw portion 20 is manufactured from PA12, or a photopolymerizable resin. In the exemplary embodiment described herein, the jaw portion 20 is manufactured in a single piece.

[0073] The process of manufacturing the jaw portion 20 can further include, for example, finishing sub-steps. However, parts manufactured by additive manufacturing typically require very little or no finishing touches, and therefore such finishing steps are optional.

[0074] In accordance with one aspect of the present subject matter, shell 32 includes complementary positioning members 36 . A complementary locating member 36 of the shell 32 is configured to interact with a locating member disposed within the insert, the overmolding of which is specifically performed to form the slide link. In the exemplary embodiment shown, the complementary locating member 36 forms the male portion of the dovetail assembly.

[0075] In this exemplary embodiment, the complementary positioning member 36 includes an axial stop 36b for arresting translational movement of the jaw portion 20 during interaction of the complementary positioning member 36 with the positioning member 28. Generally, as used herein, an "insert" thus refers to an object that is intended to be inserted into a mold to be overmolded. Thus, in the context of this embodiment, the insert is the jaw portion 20 .

[0076] 5, the jaw portion 20 includes a positioning member 28. The positioning member 28 is made from the positioning member model 8. In this case, the positioning member 28 now includes a groove 28a. According to the illustrated example, the positioning member 28 also includes a catch 28b formed in the front of the jaw portion 20.

[0077] Accordingly, complementary positioning members 36 of shell 32 are configured to interact with positioning members 28 of jaw portion 20 .

[0078] The complementary positioning members 36 are disposed on the bottom 35 of the shell 32. In particular, the complementary positioning members 36 protrude from the bottom 35 of the shell 32.

[0079] According to the example shown, the complementary positioning member 36 here comprises a tab 36a having a shape complementary to that of the groove 28a, for example a cross-section complementary to that of the groove 28a.

[0080] Tab 36a protrudes from bottom 35 of shell 32. The tab extends longitudinally according to axis G shown in Fig. 5. The longitudinal axis G of tab 36a is parallel to the flat surface formed by bottom 35 of shell 32 such that the translational movement obtained during interaction between tab 36a and groove 28a is performed parallel to the flat surface formed by bottom 35 of shell 32.

[0081] Thus, during interaction between positioning member 28 and complementary positioning member 36 , jaw portion 20 is moved parallel to the flat surface of bottom 35 of shell 32 .

[0082] In the illustrated exemplary embodiment, the groove 28a forms the female part of the dovetail assembly. The groove 28a includes, for example, a polygonal, more precisely a trapezoidal, cross section. In the illustrated exemplary embodiment, the tab 36a forms the male part of the dovetail assembly.

[0083] The dovetail assembly here is used to prevent movement of the jaw portion 20 in an out-of-plane direction, e.g., perpendicular to the flat surface of the bottom 35 of the shell 32, and also to hold the jaw portion 20 in place during separation of the complementary shell 34 and shell 32, e.g., after the process of creating an imprint, which will be described in more detail below.

[0084] Of course, the groove 28a of the positioning member 28 according to the invention and / or the tab 36a of the complementary positioning member 36 can have any other shape, as long as they allow interaction by a sliding link. Thus, in a non-illustrated embodiment, the positioning member 28 comprises a tab protruding against the underside of the jaw portion, and the complementary positioning member comprises a groove having a cross section complementary to the tab of the positioning member. According to the illustrated example, an axial stop 36b is configured to interact with the positioning member 28, more specifically with the front part of the jaw portion 20, and optionally with a catch 28b of the positioning member 28. This axial stop 36b also forms a reference for the positioning of the jaw portion 20 on the shell 32.

[0085] The axial stop 36b is formed by protruding surfaces extending perpendicularly on either side of the tab 36a, so that the complementary positioning member 36 has the shape of a T. The axial stop 36b is located at the end of the tab 36a so that it is possible to visualize an insert, such as the jaw portion 20, and in this case a bearing abutting the stop 28b of the positioning member 28.

[0086] Of course, the axial stop 36b of the complementary positioning member 36 is not limited to the illustrated example and can be formed by any other means making it possible to stop the translational movement of the insert. In a non-illustrated embodiment, the groove 28a formed by the positioning member 28 does not pass completely through, but is stopped by the longitudinal end of the tab 36a.

[0087] FIG. 6 shows the imprint 39 obtained after separation of the complementary shell 34 and the shell 32 carrying the jaw portion 20, i.e. when the shell mould 30 is open.

[0088] According to the example shown, the imprint 39 is formed from the feedstock introduced by the casting hole 38. Thus, in this embodiment, the imprint 39 is integrally contained in the complementary shell 34 of the shell mould 30.

[0089] As also shown in Fig. 6, the method includes the step of drilling a supply channel 37a starting from at least one of the casting holes 38 of the complementary shell 34 and opening into the imprint 39. Such a supply channel 37a is for example made using a cannula 37b, for example a hollow cannula, which is inserted through one of the casting holes 38. Without being limiting, the supply channel 37a preferably opens into the gum portion of the imprint 39.

[0090] Such a method therefore makes it possible to create an imprint for the purpose of producing a custom dental prosthesis by molding.

[0091] FIG. 7 illustrates the step of placing at least one artificial tooth 42 within the imprint 39 . For example, here, several artificial teeth 42 are placed in the imprint 39. These teeth are intended to fill missing teeth shown in the tooth replica model 1. Such artificial teeth 42 are then positioned in the imprint 39 in positions corresponding to the teeth previously designed by the software, as shown, for example, by hatching in Figures 3A and 3B.

[0092] FIG. 8 illustrates positioning the dental replica 10 on the shell 32 of the shell mold 30 in a manner similar to positioning the jaw portion 20 on the shell 32. For example, the tooth replica 10 as well as the formation of the jaw portion 20 are produced by additive manufacturing based on the tooth replica model 1 .

[0093] Thus, the dental replica 10 includes a positioning member 18 that is identical to the positioning member 28 of the jaw portion 20 .

[0094] In this case, the positioning member 18 now comprises a groove 18a. According to the illustrated example, the positioning member 18 also comprises a stop 18b formed by the front face of the jaw portion 20.

[0095] Accordingly, the complementary positioning member 36 of the shell 32 is configured to interact with the positioning member 18 of the tooth replica 10. In this manner, the tooth replica 10 is positioned on the shell 32 in a similar or identical manner to the jaw portion 20. In particular, the complementary positioning member 36 is configured to form a slide link, more specifically a dovetail assembly, with the positioning member 18.

[0096] The slide link here allows translational movement of the tooth replica 10 according to the longitudinal axis G of the tab 36 a , i.e. parallel to the flat surface of the bottom 35 of the shell 32 .

[0097] The dovetail assembly is used to prevent movement of the tooth replica 10 in a direction perpendicular to the flat surface of the bottom 35 of the shell 32 and to hold the tooth replica 10 in place during separation of the complementary shell 34 and shell 32, for example, after the filling material casting process described in more detail below.

[0098] 9 illustrates the process of placing the tooth replica 10 within the imprint 39. For example, this process may include closing the shell mold 30 by interaction of the shell 32 with the complementary shell 34, with the tooth replica 10 being placed on the shell 32 and the imprint 39 being within the complementary shell 34.

[0099] The tooth replica 10 forms a sealed link with the imprint 39. This is explained in particular by the fact that the submaxillary part is identical to the lower part of the tooth replica 10.

[0100] However, due to its different side portions, the tooth replica 10 only partially fills the imprint 39 and creates a residual volume within the imprint 39. This residual volume is defined and bounded by the imprint 39, the artificial tooth 42 and the tooth replica 10.

[0101] In the case of a partial dental prosthesis, this volume is further defined by a Stellite chassis 44 (FIG. 11) that is pre-placed over the tooth replica 10 prior to closing the shell mold 30.

[0102] 10 shows a casting process in which a filling material 46 is introduced via at least one casting hole 38 into at least the residual volume defined between the tooth replica 10 and the imprint 39. In this case, in the example shown, the filling material 46 is introduced via the supply channel 37a.

[0103] During this process, the filling material 46 contacts and bonds, for example by overmolding, to at least a portion of the artificial tooth 42. The same applies to the Stellite chassis 44 in the case of a partial prosthesis.

[0104] The filling material 46 can be injected under pressure or by natural gravity filling, as best conforms to the walls of the remaining volume. The filling material 46 can include any type of material known for the manufacture of dental prostheses, such as, for example, an acrylic resin.

[0105] The method further includes a step of separating the tooth replica 10 and the imprint 39, or for example, a step of opening the shell mold 30, and then a step of extracting a non-surface blank configured to form a dental prosthesis (not shown).

[0106] The method may also include a finishing step, which may include, for example, removing an injection sprue corresponding to the shaping of the feed channel, and / or a finishing step including, for example, polishing and / or deburring and / or buffing a non-surface blank.

[0107] 11 shows an example of a prosthesis 40 obtained after this method according to an exemplary embodiment. According to the illustrated example, the prosthesis 40 includes artificial teeth 42 and a Stellite chassis 44 bonded to a hardened filling material 46 that forms a gum.

[0108] In this exemplary embodiment, the dental prosthesis 40 is a partial dental prosthesis. In effect, a Stellite chassis 44 connects two parts, each of which includes at least one artificial tooth 42 bonded to a hardened filling material 46.

[0109] The preparation process may be performed by placing the dental prosthesis 40 on the tooth replica 10 before it is inserted into the patient's mouth.

[0110] FIG. 12 shows a schematic diagram of an exemplary embodiment of a method for manufacturing a dental prosthesis according to the invention. The manufacturing method according to this example is as follows: As illustrated in FIG. 1 , a step S1 of digitally designing a dental prosthetic model produced on the basis of a replica model of a patient's tooth 1; A step S2 in which a positioning member model 8 is digitally designed on the tooth replica model 1; a step S3 of parallelizing the tooth replica model 1, in which the undercut zones are digitally filled; Step S4 of creating a partial jaw model 2 including a tooth replica model 1 and a model of a dental prosthesis assembled on the tooth replica model 1, as shown in FIGS. 3A and 3B; A step S5 comprising manufacturing the jaw portion 20 based on the jaw portion model 2 including the positioning member 28, for example by additive manufacturing; A step S6 comprising manufacturing a tooth replica 10, for example by additive manufacturing, on the basis of a tooth replica model 1 including a positioning member 18; a step S7 of positioning the jaw portion 20 on the shell 32 of the shell mold 30 by interaction of a positioning member 28 of the jaw portion 20 with a complementary positioning member 36 disposed within said shell 32, as shown in FIG. Once the jaw members 20 are positioned over the shell 32 during step S8, the shell mold 30 is closed, as shown in FIG. a step S9 of making an imprint 39 of the jaw portion, which is carried out by injection of material into the shell mould 30 (20), forming an imprint 39 of the jaw portion; A step S10 of drilling a supply flow passage that opens into the imprint 39; As shown in FIG. 7, a step S11 of positioning at least one artificial tooth within the imprint of the jaw portion 20; a step S12 (e.g., as shown by FIG. 8 ) of positioning the tooth replica 10 on the shell 32 of the shell mold 30 by interaction of the positioning members 18 of the tooth replica 10 with the complementary positioning members 36 of the shell 32; When a partial dental prosthesis is involved, a step S13 of placing a Stellite chassis 44 on the tooth replica 10; A step S14 (for example, as shown by FIG. 9 ) of positioning a tooth replica 10 within an imprint 39 in which at least one artificial tooth 42 is to be positioned; and step S15 (eg, as shown in FIG. 10) of pouring a filling material 46 into the remaining volume defined by the imprint 39, the at least one artificial tooth 42, and the tooth replica 10.

Claims

1. A method for manufacturing a dental prosthesis, comprising the steps of: The method comprises the following successive steps: - digitally designing a dental prosthesis model (4) produced from a patient's tooth replica model (1); A step of creating a partial jaw model (2) including the tooth replica model (1) and the dental prosthesis model (4) assembled to the tooth replica model (1); - digitally designing a positioning member model (8) within said tooth replica model (1); manufacturing a jaw section (20) including a positioning member (28) based on said jaw section model (2) including a positioning member model (8); producing a tooth replica (10) including a positioning member (18) based on said tooth replica model (1) including said positioning member model (8); positioning the jaw portion (20) on a shell (32) of a shell mold (30) by interaction of the positioning member (28) of the jaw portion (20) with a complementary positioning member (36) disposed within the shell (32); closing the shell mold (30); creating an imprint (39) of the jaw portion (20) by injection of material into the shell mould (30); Positioning at least one artificial tooth (42) within the imprint (39) of the jaw portion (20); positioning the tooth replica (10) on the shell (32) of the shell mold (30) by interaction of the positioning members (18) of the tooth replica (10) with the complementary positioning members (36) of the shell (32); placing the tooth replica (10) within the imprint (39) in which the at least one artificial tooth (42) is placed; pouring a filling material (46) into a remaining volume defined by said imprint (39), said at least one artificial tooth (42) and said tooth replica (10); A manufacturing method comprising:

2. The method of claim 1, wherein the positioning members (18, 28) interact with the complementary positioning members (36) disposed on the shell (32) via a sliding link.

3. 3. The method according to claim 1 or 2, wherein the step of producing the tooth replica (10) is preceded by a step of translating the tooth replica model (1) and wherein undercut zones are digitally filled.

4. The method according to any one of claims 1 to 3, wherein the step of positioning the tooth replica (10) in the imprint (39) precedes a step of positioning a Stellite chassis (44) on the tooth replica (10).

5. The method according to any one of the preceding claims, further comprising the step of drilling supply channels (37a) opening into the imprint (39).

6. The method according to any one of the preceding claims, wherein the step of manufacturing the jaw portion (20) and / or the tooth replica (10) is performed by additive manufacturing.

7. 7. A method according to claim 6, wherein the steps of manufacturing the jaw portion (20) and / or the tooth replica (10) are carried out according to a method comprising successive application of material by jets on a print support in successive layers, said material being solidified by photopolymerization after each jet.

8. 1. A shell mold for producing a dental prosthesis, comprising: a shell (32) including complementary positioning members (36) configured to interact with positioning members (18, 28) of an insert (10, 20) disposed within the shell mold (30).

9. The shell mold of claim 8, wherein the complementary positioning member (36) is configured to form a slide link with the positioning member (18, 28) of the insert (10, 20).

10. The shell mould of claim 8 or 9, characterized in that the complementary positioning member (36) is configured to form a dovetail assembly with the positioning member (18, 28).

11. The shell mold of claim 10, wherein the complementary locating member (36) is configured to form a male portion of the dovetail assembly.

12. The shell mould according to any one of claims 8 to 11, characterized in that the complementary positioning members (36) include tabs (36a) configured to interact with the positioning members (18, 28).

13. The shell mould according to any one of claims 8 to 12, characterized in that the complementary positioning members (36) include axial stops (36b).

14. The complementary positioning member (36) includes an axial stop (36b); 13. The shell mold of claim 12, wherein the axial stop (36b) is formed by protruding surfaces extending perpendicularly on either side of the tab (36a), and the complementary positioning member (36) has a T-shape.

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