Method for manufacturing dental prostheses and shell mold configured to carry out this manufacturing method.

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 producing a full 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 production method. BACKGROUND ART

[0002] A dental prosthesis refers to a device intended to replace at least part of a person's natural teeth. A removable dental prosthesis is, for example, a prosthesis that can be removed from the mouth for daily maintenance or during sleep. A "full" dental prosthesis, also called a denture, refers to a prosthesis that replaces all teeth, whether it is a maxillary denture or a mandibular denture. A "partial" dental prosthesis is used when it is necessary to replace only one tooth, or only some but not all of the teeth.

[0003] As such, partial prostheses conventionally consist of a metal chassis (stellite) that is used to support artificial teeth placed at the positions of missing teeth. This metal chassis (usually containing chromium-cobalt-molybdenum) has high rigidity and places a burden on both the remaining teeth and the mucosa (mainly the gums).

[0004] Dental prostheses may also be held in place in the oral cavity by at least one implant. An implant is a metallic element that is secured to the bone, optionally via a screw, to replace the root of a tooth.

[0005] The manufacture of dental prostheses requires the implementation of a protocol consisting of a series of highly precise steps, one of which is a step called flask molding. This step comprises imprinting a wax prosthesis model into a mold consisting of two separable parts called a flask. This model is manually created by a prosthetist, and artificial teeth are sequentially placed on the model.

[0006] In some cases, an imprint is created by pouring plaster into a flask. Once the plaster has hardened, the flask is heated to melt the wax, leaving the imprint within the plaster. A mold made of plaster needs to cool before the material (generally resin) is cast into the mold, which already has the artificial teeth positioned.

[0007] In other cases, the imprint is made by pouring gel into a flask. Once the gel has solidified, the wax model can then be removed manually without a thermal decomposition step. However, the artificial tooth must be separated from the wax model before it can be placed in the imprint formed by the gel. Furthermore, the artificial tooth is generally heated to remove any wax residue. This flask fabrication process, particularly the solidification of the plaster, heating the flask, cooling, and separating the artificial tooth from the wax model, is time-consuming and significantly delays the effective fabrication of the prosthesis. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Therefore, the present invention aims to overcome these drawbacks at least in part. The present invention aims to propose a manufacturing method that saves time and increases the ease of manufacturing dental prostheses. [Means for solving the problem]

[0009] For this purpose, according to a first aspect of the present invention, the present invention relates to a method for manufacturing a dental prosthesis, which includes the following: The process of digitally designing dental prosthesis models from patient tooth replica models, A process for creating a jaw model that includes a tooth replica model and a dental prosthesis model assembled on the tooth replica model, The process of digitally designing positioning component models in tooth replica models, A process for manufacturing a jaw portion including a positioning member based on a jaw portion model including a tooth positioning member model, A process for manufacturing a tooth replica including a positioning member based on a tooth replica model including a positioning member model, The process involves positioning the jaw portion on the shell of the shell mold through the interaction between a positioning member for the jaw portion and a complementary positioning member placed inside the shell, The process of closing the shell mold, The process involves creating an imprint of the jaw portion by injecting material into a shell mold, A step of positioning at least one artificial tooth within the imprint of the jaw area, The process involves positioning the tooth replica on the shell of the shell mold through the interaction between the tooth replica positioning member and the shell's complementary positioning member, The process involves placing a tooth replica within an imprint in which at least one artificial tooth is to be placed, A manufacturing method comprising the steps of imprinting, casting a filling material into a remaining volume defined by at least one artificial tooth and a tooth replica.

[0010] Therefore, such a manufacturing method for producing dental prostheses according to the present invention allows for time savings by avoiding steps such as heating and cooling the flask.

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

[0012] Therefore, since the jaw portion is a single unit and is not necessarily reused in the rest of the manufacturing process, there is no need to remove or heat the artificial teeth, and the artificial teeth can be placed directly after imprinting, eliminating the usual procedures of heating and retrieving the artificial teeth.

[0013] Furthermore, the material forming the jaw portion can then be recycled to enable the manufacture of other dental prostheses or other products. The same applies to the material forming the tooth replica, which can be manufactured in the same manner as the jaw portion.

[0014] In an exemplary embodiment, the step of manufacturing the jaw portion and the step of manufacturing the tooth replica are performed simultaneously. This makes it possible to reduce the manufacturing time of the prosthesis.

[0015] Therefore, the manufacturing method according to the present invention makes it possible to easily and quickly obtain a custom-made, i.e., ordered, dental prosthesis.

[0016] Furthermore, by using the patient's tooth replica for the manufacture of the prosthesis, more precisely during the step of pouring the filling material, it is 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 the positioning members on the tooth replica, and thus on the jaw portion, allows more accurate positioning of these two elements on the shell of the shell mold via the complementary positioning members. This therefore makes it possible to position the tooth replica more accurately inside the imprint of the jaw portion.

[0018] The positioning members are also used to hold the jaw portion or the tooth replica in place on the shell of the shell mold, particularly when it interacts with the complementary positioning members. Such positioning members are formed, for example, on the lower part of the tooth replica.

[0019] According to a preferred example, the positioning members interact with complementary positioning members arranged on the shell according to a sliding link.

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

[0021] In this way, the movement of the jaw portion or the tooth replica relative to the shell is limited to translational motion along a single axis defined by the slide link. Therefore, it is possible to adjust the position in the translational motion along the axis defined by at least one slide link of the jaw portion or the tooth replica.

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

[0023] According to another preferred example, 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 form the female part of a dovetail assembly through interaction with the complementary positioning member.

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

[0026] According to an option of interest, the complementary positioning member further comprises an axial stop. For example, this axial stop can allow the translational movement of the jaw portion or the tooth replica to be stopped when the positioning member interacts with the complementary positioning member along the slide link. Thus, the axial stop forms a reference for positioning the jaw portion and / or the tooth replica relative to the shell. In fact, it is possible to fix the jaw portion and / or the tooth replica in a predetermined position by sliding along the axis defined by the slide link up to the axial stop.

[0027] Therefore, positioning the jaw portion on the shell can be easily and quickly performed by a prosthodontist or any other practitioner by translating the jaw portion until it stops. Furthermore, by doing so, it is possible to position a tooth replica on the shell in the same manner.

[0028] In an exemplary embodiment, prior to the process of manufacturing the tooth replica, there is a step of translating the tooth replica model, in which the undercut zones of the tooth replica model are digitally filled in. These undercut zones are typically located at the junction between the tooth and the gum. Conventional methods required manually filling these undercut zones with wax.

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

[0030] Therefore, this process is performed digitally, which then allows for the manufacture of a tooth replica in which the "parallelized" zones are formed integrally with the tooth replica.

[0031] This is particularly advantageous during the process of creating the imprint, as it allows for the removal of the jaw portion from the mold without damaging the imprint.

[0032] Furthermore, undercut areas are sometimes filled according to an insertion axis determined digitally. The insertion axis corresponds to the direction in which the prosthesis is inserted into the patient's mouth. The insertion axis is generally determined by the physician or by some software.

[0033] According to a particular exemplary embodiment, the step of positioning the Stellite chassis onto the tooth replica precedes the step of positioning the imprint onto the tooth replica. Stellite chassis are particularly useful in the case of partial prostheses, typically holding together two separate parts of the prosthesis. Advantageously, the stellite chassis is securely attached to the dental prosthesis after the filling material has been cast.

[0034] Therefore, positioning the Stellite chassis is easy and quick for the operator, ensuring optimal adaptation to the environment in which it is intended to be placed.

[0035] According to another exemplary embodiment, this method further includes the step of perforating a supply channel opening in the imprint. This supply channel is then used to cast the filling material and fabricate a dental prosthesis. In the example of interest, at least two channels are drilled to allow for the simultaneous casting of the filling material and the removal of air present in the imprint.

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

[0037] According to this invention, "additive manufacturing" refers to a manufacturing method that involves adding material, which is almost always computer-assisted and more commonly called "3D printing." Additive manufacturing technology enables, for example, the more precise manufacturing of jaw portions. Therefore, there is no need to manufacture wax models by hand.

[0038] Furthermore, the precision of additive manufacturing can potentially eliminate the need for polishing processes, which are often time-consuming, costly, and can damage parts.

[0039] Therefore, in certain cases, the dental prosthesis produced can be ready for direct use in such a method, or it can be completed with only minimal post-processing steps to obtain, for example, a polished mirror-like appearance on a portion of the surface of the dental prosthesis.

[0040] According to exemplary embodiments, the process of manufacturing the jaw portion and / or tooth replica is carried out according to a method comprising the continuous addition of material by jetting onto a print support in continuous layers, the material being solidified by photopolymerization after each jet.

[0041] For example, the jaw portion can be manufactured from a monomer, polymer, or photopolymerizable resin. Preferably, the jaw portion is manufactured from PA12 (also called nylon 12 in the case of polyamide 12).

[0042] In fact, PA12 has the desirable ability to recycle the non-molten powder after carrying out an additive manufacturing method as described herein, and thus allows the powder to be reused to manufacture other prostheses or even further products.

[0043] In another embodiment, a shell mold for manufacturing dental prostheses is also proposed. According to 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. Therefore, such molds are configured to carry out the methods described above.

[0044] In the context of this invention, "shell mold" refers to a mold formed by at least two interacting parts, and each part is therefore called a "shell".

[0045] The insert, in this context, corresponds to any part that enables the carrying out of at least one of the steps of imprinting, molding, or overmolding in order to fabricate a dental prosthesis. For example, according to the present invention, the insert may be a replica of a patient's tooth or jaw portion.

[0046] Therefore, such shell molds have similar advantages to those described above in terms of method.

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

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

[0049] According to one embodiment, a 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 stopper that, when it interacts with the complementary positioning member, prevents the translational motion of the positioning member. In particular, the axial stopper can be formed perpendicular to both sides of the tab, for example, by a protruding surface that projects laterally relative to the longitudinal direction of the tab and acts as a guide for translational motion, resulting in a complementary positioning member having a T-shape. [Brief explanation of the drawing]

[0051] The present invention, according to exemplary embodiments, will be fully understood and its advantages will become clearer upon reading the following detailed description, which is given for informational purposes only and not intended to be limiting, with reference to the accompanying drawings. [Figure 1] Figure 1 shows an example of a patient's tooth replica model according to an embodiment of the present invention. [Figure 2A] Figure 2A is a frontal high-angle view of an example of the patient tooth replica model from Figure 1, equipped with a positioning member. [Figure 2B] Figure 2B is a rear view of the tooth replica model shown in Figure 2A, displayed at a substantially low angle. [Figure 3A] Figure 3A shows an example of a jaw portion model from a high angle, as obtained from the tooth replica examples in Figures 2A and 2B, according to an embodiment of the present invention. [Figure 3B] Figure 3B is a posterior view of the jaw model example shown in Figure 3A, presented at a substantially low angle. [Figure 4]Figure 4 shows the positioning of the jaw portion on the shell of the shell mold, as performed using the jaw portion models of Figures 3A and 3B, according to an exemplary embodiment of the present invention. [Figure 5] Figure 5 is a perspective view showing the process of closing the shell mold with a jaw portion positioned on one of the shells, as shown in Figure 4. [Figure 6] Figure 6 shows the process of imprinting the jaw portion created within the shell mold and forming the supply channel. [Figure 7] Figure 7 shows the process of positioning the artificial teeth in the imprint shown in Figure 6. [Figure 8] Figure 8 shows the process of placing the tooth replicas, fabricated from the tooth replica models in Figures 2A and 2B, onto the shell of the shell mold in Figure 4. [Figure 9] Figure 9 is a perspective view showing the process of closing the shell mold with a tooth replica placed on one of the shells, as shown in Figure 8. [Figure 10] Figure 10 shows the process of pouring filling material into a closed shell mold containing tooth replicas as shown in Figures 8 and 9. [Figure 11] Figure 11 shows a dental prosthesis obtained according to an exemplary embodiment of the present invention. [Figure 12] Figure 12 is a schematic diagram illustrating a method for manufacturing a dental prosthesis according to an exemplary embodiment of the present invention. [Modes for carrying out the invention]

[0052] The same elements shown in the aforementioned drawings are identified by the same reference numeral. Figure 1 shows a replica model of the patient's teeth (1). Such models can be obtained, for example, through a process of taking a digital technology imprint (not shown) on a plaster model via a table scanner, or preferably directly via an intraoral scanner in the patient's oral cavity.

[0053] Therefore, tooth replica model 1 corresponds to a digital representation of a portion of the patient's jaw, in this case the mandibular portion on which a dental prosthesis must be fabricated.

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

[0055] Tooth replica model 1 includes, for example, an "upper" portion that mainly forms the tooth and a "lower" portion that mainly forms the gum. Tooth replica model 1 further includes 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 on top.

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

[0057] Of course, the present invention is not limited to this type of dental prosthesis, but also applies to other types of prostheses, such as complete dental prostheses, i.e., those in which the tooth replica model does not include tooth 5.

[0058] As shown in Figures 2A and 2B, the tooth replica model 1 also includes an anterior portion representing a convex outer surface. Thus, the anterior portion is opposite to the posterior portion, and the distance separating them forms the thickness of the tooth replica model 1. Tooth replica model 1 further includes a lower surface 7 in its lower portion. This surface is configured to be stably positioned on the support once the tooth replica model 1 is manufactured. The lower surface 7 of the lower part of tooth replica model 1 defines, for example, a plane.

[0059] Figures 2A and 2B also show the positioning member model 8 positioned below the tooth replica model 1. In particular, the positioning member model 8 is positioned starting from the lower 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 sliding link with a complementary member.

[0060] In practice, the groove 8a extends along the longitudinal axis between the rear and front parts of the tooth replica model 1. The groove 8a has a trapezoidal cross-section that allows movement only along the longitudinal axis of the groove 8a, due to interaction with a complementary member.

[0061] In the examples shown in Figures 2A and 2B, the groove 8a is cut out starting from the bottom surface 7 of the tooth replica model 1. The groove 8a extends parallel to the plane defined by the bottom surface 7 over at least a portion of the thickness of the tooth replica model 1. For example, in Figure 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 is completely through. In this exemplary embodiment, the positioning member model 8 also includes a fastener element or fastener 8b configured to stop the translational motion of the tooth replica model 1. Depending on the choice of interest, the fastener is formed by the front of the tooth replica model 1. In this embodiment, the fastener 8b includes a projection extending from the front of the tooth replica model 1. The projection of the fastener 8b includes a flat surface perpendicular to the longitudinal axis of the groove 8a.

[0062] Figures 3A and 3B show a jaw model 2 that includes tooth replica model 1 shown in Figures 2A and 2B, and a dental prosthesis model 4, which is shown in hatching and assembled on tooth replica model 1 by digital technology design.

[0063] Dental prosthesis model 4 is digitally designed based on tooth replica model 1. To ensure optimal adaptation, the profile and shape of the denture model are determined according to tooth replica model 1. The profile of dental prosthesis model 4 is also determined according to the insertion axis, i.e., the trajectory for inserting the dental prosthesis model into the patient's mouth through simulation. This insertion axis is determined, for example, by the denture wearer or by software.

[0064] Therefore, the dental prosthesis model 4 typically includes at least one tooth and optionally a gingival portion by a tooth replica model 1, so as to form a jaw portion model 2 with corrected complete teeth.

[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 against at least one remaining tooth 5 and / or mucosa, particularly the gingiva, and / or to hold together at least two separate parts of the dental prosthesis model.

[0066] It is understood that the lower portion of jaw model 2 corresponds perfectly to the lower portion of tooth replica model 1. In fact, only the hatched portion shown on jaw model 2 differs from tooth replica model 1. Thus, jaw model 2 also includes a lower surface 7 at its lower end. Therefore, jaw model 2 also has a positioning member model 8, which is identical to the positioning member of tooth replica model 1, and here includes a groove 8a and a fastener 8b.

[0067] Figure 4 shows the process of positioning the jaw portion 20 on the shell 32 of the shell mold 30. The shell mold 30 here includes two shells: the shell 32 and a complementary shell 34 configured to interact with the shell 32 in order to close the shell mold 30.

[0068] For this purpose, the shell 32 and the complementary shell 34 include a notch 33a and a hook 33b, respectively. The hook 33b is configured to interact with the notch 33a to hold the shell mold 30 in a closed position. Of course, any other means for closing the shell mold 30, such as a rubber band, are possible.

[0069] The shell 32 has a bottom 35, which 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] In the illustrated example, the casting hole 38 is located within the complementary shell 34 to fill the shell mold 30 with material for forming the imprint of the insert. The material used to form the imprint is a hydrophilic colloidal gel. Such a shell mold 30 can be used to form, for example, a dental flask.

[0071] Figure 4 also shows an exemplary embodiment of the jaw portion 20 fabricated from the jaw portion model 2 shown in Figures 3A and 3B.

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

[0073] The process for manufacturing the jaw portion 20 may further include, for example, a finishing sub-process. However, parts manufactured by additive manufacturing generally require only very slight finishing touches, or no finishing touches at all. Therefore, such finishing processes are optional.

[0074] According to one aspect of the object of the present invention, the shell 32 includes a complementary positioning member 36. The complementary positioning member 36 of the shell 32 is configured to interact with a positioning member positioned within the insertion, and its overmolding is performed specifically to form a slide link. In the illustrated exemplary embodiment, the complementary positioning member 36 forms the male portion of the dovetail assembly.

[0075] In this exemplary embodiment, the complementary positioning member 36 includes an axial stopper 36b for stopping the translational motion of the jaw portion 20 during the interaction between the complementary positioning member 36 and the positioning member 28. Generally, as used herein, “insert” refers to an object that is intended to be inserted into a mold to be overmolded. Therefore, in the context of this embodiment, the insert is the jaw portion 20.

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

[0077] Therefore, the complementary positioning member 36 of the shell 32 is configured to interact with the positioning member 28 of the jaw portion 20.

[0078] The complementary positioning member 36 is positioned at the bottom 35 of the shell 32. In particular, the complementary positioning member 36 protrudes from the bottom 35 of the shell 32.

[0079] In the illustrated example, the complementary positioning member 36 comprises a tab 36a having a shape complementary to the shape of the groove 28a. The tab 36a, for example, has a cross-section complementary to the cross-section of the groove 28a.

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

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

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

[0083] The dovetail assembly is used here to prevent the jaw portion 20 from moving out of plane, for example, in a direction perpendicular to the flat surface of the bottom 35 of the shell 32, and to hold the jaw portion 20 in place during the separation of the complementary shell 34 and the shell 32, for example, 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 and / or the tab 36a of the complementary positioning member 36 according to the present invention can have any other shape, as long as it allows interaction by a slide link. Thus, in embodiments not shown, the positioning member 28 includes a tab protruding from the lower surface of the jaw portion, and the complementary positioning member includes a groove having a cross-section complementary to the tab of the positioning member. According to the illustrated example, the axial stopper 36b is configured to interact with the positioning member 28, more specifically the front portion of the jaw portion 20, and optionally with the stopper 28b of the positioning member 28. This axial stopper 36b also forms a reference for positioning the jaw portion 20 on the shell 32.

[0085] The axial stopper 36b is formed by protruding surfaces extending perpendicularly from both sides of the tab 36a, so that the complementary positioning member 36 has a T-shape. The axial stopper 36b is located at the end of the tab 36a so that the insert, such as the jaw portion 20, and the bearing that contacts the stopper 28b of the positioning member 28 in this case can be visualized.

[0086] Of course, the axial stopper 36b of the complementary positioning member 36 can be formed by any other means that enables stopping the translational motion of the insert, and is not limited to the illustrated examples. In an embodiment not shown, the groove 28a formed by the positioning member 28 is not fully passed through but is stopped by the longitudinal end of the tab 36a.

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

[0088] In the illustrated example, the imprint 39 is formed from the raw material introduced through the casting hole 38. Therefore, in this embodiment, the imprint 39 is integrally included in the complementary shell 34 of the shell mold 30.

[0089] As shown in Figure 6, the method includes the step of drilling a supply channel 37a that opens into the imprint 39, starting from at least one of the casting holes 38 of the complementary shell 34. Such a supply channel 37a is made using, for example, a cannula 37b, such as a hollow cannula, which is inserted through one of the casting holes 38. Not limited to, the supply channel 37a preferably opens in the gingival portion of the imprint 39.

[0090] Therefore, such a method makes it possible to create imprints for the purpose of fabricating custom dental prostheses by molding.

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

[0092] Figure 8 shows the process of positioning the tooth replica 10 on the shell 32 of the shell mold 30 in the same manner as the process of positioning the jaw portion 20 on the shell 32. For example, the tooth replica 10 is fabricated by additive manufacturing based on the tooth replica model 1, similar to the formation of the jaw portion 20.

[0093] Therefore, the tooth replica 10 includes the same positioning member 18 as the positioning member 28 of the jaw portion 20.

[0094] In this case, the positioning member 18 includes a groove 18a. According to the illustrated example, the positioning member 18 also includes a fastener 18b formed by the front surface of the jaw portion 20.

[0095] Therefore, 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 way, the tooth replica 10 is positioned on the shell 32 in the same manner as, or identically 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 the translational motion of the tooth replica 10 along the longitudinal axis G of tab 36a, that is, parallel to the flat surface of the bottom 35 of the shell 32.

[0097] The dovetail assembly is used to prevent the tooth replica 10 from moving 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 the separation of the complementary shell 34 and the shell 32 after the casting process of the filling material, for example, which is described in more detail below.

[0098] Figure 9 shows the process of placing the tooth replica 10 within the imprint 39. For example, this process includes closing the shell mold 30 through the interaction of the shell 32 and the complementary shell 34, with the tooth replica 10 placed on the shell 32 and the imprint 39 inside 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 submandibular portion is identical to the lower portion of the tooth replica 10.

[0100] However, since the tooth replica 10 has a different lateral portion, it only partially fills the imprint 39, creating a residual volume within the imprint 39. This residual volume is defined and its boundaries are established by the imprint 39, the artificial tooth 42, and the tooth replica 10.

[0101] In the case of partial dental prostheses, this volume is further defined by the Stellite chassis 44 (Figure 11) pre-positioned on the tooth replica 10 before closing the shell mold 30.

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

[0103] During this process, the filling material 46 comes into contact with and bonds to at least a portion of the artificial tooth 42, for example, by an overmolding. 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 to best conform to the walls of the residual volume. The filling material 46 may include any type of material known for the manufacture of dental prostheses, such as acrylic resin.

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

[0106] This method may also include a finishing step, for example, a step of removing the injection sprue corresponding to the molding of the supply channel, and / or a finishing step, for example, polishing and / or deburring and / or buffing of the non-surface blank.

[0107] Figure 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 an artificial tooth 42 and a stellite chassis 44 bonded to a solidifying filling material 46 that forms a gum.

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

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

[0110] Figure 12 schematically shows an exemplary embodiment of the method for manufacturing a dental prosthesis according to the present invention. The manufacturing method in this example is: As illustrated in Figure 1, the process S1 involves digitally designing a dental prosthetic model based on a replica model of the patient's tooth 1, The positioning member model 8 is designed digitally in the tooth replica model 1 in step S2, Step S3 involves parallelizing tooth replica model 1, where the undercut zone is digitally filled, As shown in Figures 3A and 3B, step S4 is to create a jaw portion model 2 which includes a tooth replica model 1 and a model of a dental prosthesis assembled on the tooth replica model 1. Step S5 includes manufacturing a jaw portion 20, for example by additive manufacturing, based on a jaw portion model 2 including a positioning member 28, Step S6 includes manufacturing a tooth replica 10, for example by additive manufacturing, based on a tooth replica model 1 including a positioning member 18, As shown in Figure 4, the jaw portion 20 is positioned on the shell 32 of the shell mold 30 by the interaction between the positioning member 28 of the jaw portion 20 and the complementary positioning member 36 arranged inside the shell 32, in step S7. During step S8, once the jaw portion 20 is positioned on the shell 32, the shell mold 30 is closed, as shown in Figure 5. Step S9 is a step of creating an imprint 39 of the jaw portion, which is performed by injecting material into a shell mold 30 (20), and is a step of forming an imprint 39 of the jaw portion. Step S10 involves drilling a supply channel that opens into the imprint 39, As shown in Figure 7, step S11 involves positioning at least one artificial tooth within the imprint of the jaw portion 20, The interaction between the positioning member 18 of the tooth replica 10 and the complementary positioning member 36 of the shell 32 is used to position the tooth replica 10 on the shell 32 of the shell mold 30 in step S12 (shown, for example, in Figure 8), When a partial dental prosthesis is involved, the process includes S13 of placing the Stellite chassis 44 on the tooth replica 10, Step S14 (for example, shown by Figure 9) involves positioning a tooth replica 10 within an imprint 39 in which at least one artificial tooth 42 is positioned, The process includes step S15 (for example, shown in Figure 10) of pouring a filling material 46 into the remaining volume defined by the imprint 39, at least one artificial tooth 42, and tooth replica 10. The following are some embodiments (configurations) of the present invention. [Aspect 1] A method for manufacturing dental prostheses, The manufacturing method consists of the following series of steps, namely, The process involves digitally designing a dental prosthesis model (4) that is created from a patient's tooth replica model (1), A step of creating a jaw portion model (2) which includes the tooth replica model (1) and the dental prosthesis model (4) assembled to the tooth replica model (1), The process of digitally designing a positioning member model (8) within the tooth replica model (1), A step of manufacturing a jaw portion (20) including a positioning member (28) based on the jaw portion model (2) including a positioning member model (8), A step of manufacturing a tooth replica (10) including a positioning member (18) based on the tooth replica model (1) including the positioning member model (8), A step of positioning the jaw portion (20) on the shell (32) of the shell mold (30) by interaction between the positioning member (28) of the jaw portion (20) and a complementary positioning member (36) disposed within the shell (32), The process of closing the shell mold (30), The process involves injecting material into the shell mold (30) to create an imprint (39) of the jaw portion (20), The steps include positioning at least one artificial tooth (42) within the imprint (39) of the jaw portion (20), The process involves positioning the tooth replica (10) on the shell (32) of the shell mold (30) through the interaction between the positioning member (18) of the tooth replica (10) and the complementary positioning member (36) of the shell (32), The steps include: placing the tooth replica (10) within the imprint (39) in which at least one artificial tooth (42) is placed; A step of pouring filling material (46) into the remaining volume defined by the imprint (39), the at least one artificial tooth (42), and the tooth replica (10), A manufacturing method that includes the following features. [Aspect 2] The manufacturing method according to embodiment 1, wherein the positioning members (18, 28) interact with the complementary positioning member (36) disposed on the shell (32) according to a slide link. [Aspect 3] The manufacturing method according to either embodiment 1 or 2, wherein the step of manufacturing the tooth replica (10) precedes the step of translating the tooth replica model (1) and the undercut zone is digitally filled. [Aspect 4] The manufacturing method according to any one of embodiments 1 to 3, wherein the step of positioning the tooth replica (10) within the imprint (39) precedes the step of positioning the stellite chassis (44) on the tooth replica (10). [Aspect 5] The manufacturing method according to any one of embodiments 1 to 4, further comprising the step of drilling a supply channel (37a) that opens into the imprint (39). [Aspect 6] The manufacturing method according to any one of embodiments 1 to 5, wherein the step of manufacturing the jaw portion (20) and / or the tooth replica (10) is carried out by additive manufacturing. [Aspect 7] The manufacturing method according to embodiment 6, wherein the step of manufacturing the jaw portion (20) and / or the tooth replica (10) is carried out according to a method comprising the continuous addition of material by jet on a print support in continuous layers, and the material is solidified by photopolymerization after each jet. [Aspect 8] A shell mold for manufacturing dental prostheses, characterized in that the shell (32) includes a complementary positioning member (36) configured to interact with positioning members (18, 28) of inserts (10, 20) placed within the shell mold (30). [Aspect 9] The shell mold according to embodiment 8, characterized in that the complementary positioning member (36) is configured to form a slide link with the positioning members (18, 28) of the inserts (10, 20). [Aspect 10] The shell mold according to any one of embodiments 8 to 10, characterized in that the complementary positioning member (36) is configured to form a dovetail assembly together with the positioning members (18, 28). [Aspect 11] The shell mold according to embodiment 11, characterized in that the complementary positioning member (36) is configured to form the male portion of the dovetail assembly. [Aspect 12] The shell mold according to any one of embodiments 8 to 12, characterized in that the complementary positioning member (36) includes a tab (36a) configured to interact with the positioning members (18, 28). [Aspect 13] The shell mold according to any one of embodiments 8 to 12, characterized in that the complementary positioning member (36) includes an axial stopper (36b). [Aspect 14] The shell mold according to embodiments 12 and 13, characterized in that the axial stopper (36b) is formed by protruding surfaces extending perpendicularly from both sides of the tab (36a), and the complementary positioning member (36) has a T-shape.

Claims

1. A method for manufacturing dental prostheses, The manufacturing method consists of the following series of steps, namely, The process involves digitally designing a dental prosthesis model (4) that is fabricated from a patient's tooth replica model (1), A step of creating a jaw portion model (2) which includes the tooth replica model (1) and the dental prosthesis model (4) assembled to the tooth replica model (1), The process of digitally designing a positioning member model (8) within the tooth replica model (1), A step of manufacturing a jaw portion (20) including a positioning member (28) based on the jaw portion model (2) including a positioning member model (8), A step of manufacturing a tooth replica (10) including a positioning member (18) based on the tooth replica model (1) including the positioning member model (8), A step of positioning the jaw portion (20) on the shell (32) of the shell mold (30) by interaction between the positioning member (28) of the jaw portion (20) and a complementary positioning member (36) disposed within the shell (32), The process of closing the shell mold (30), The process involves injecting material into the shell mold (30) to create an imprint (39) of the jaw portion (20), The steps include positioning at least one artificial tooth (42) within the imprint (39) of the jaw portion (20), The process involves positioning the tooth replica (10) on the shell (32) of the shell mold (30) through the interaction between the positioning member (18) of the tooth replica (10) and the complementary positioning member (36) of the shell (32), The steps include: placing the tooth replica (10) within the imprint (39) in which at least one artificial tooth (42) is placed; A step of pouring filling material (46) into the remaining volume defined by the imprint (39), the at least one artificial tooth (42), and the tooth replica (10), A manufacturing method that includes the following features.

2. The manufacturing method according to claim 1, wherein the positioning members (18, 28) interact with the complementary positioning member (36) disposed on the shell (32) according to a slide link.

3. The manufacturing method according to claim 1 or 2, wherein the step of manufacturing the tooth replica (10) precedes the step of translating the tooth replica model (1) and the undercut zone is digitally filled.

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

5. The manufacturing method according to any one of claims 1 to 4, further comprising the step of drilling a supply channel (37a) that opens into the imprint (39).

6. The manufacturing method according to any one of claims 1 to 5, wherein the step of manufacturing the jaw portion (20) and / or the tooth replica (10) is carried out by additive manufacturing.

7. The manufacturing method according to claim 6, wherein the step of manufacturing the jaw portion (20) and / or the tooth replica (10) is carried out according to a method comprising the continuous addition of material by jet on a print support in continuous layers, and the material is solidified by photopolymerization after each jet.

8. The shell (32) includes a complementary positioning member (36) configured to interact with positioning members (18, 28) of the inserts (10, 20) placed within the shell mold (30), The complementary positioning member (36) is configured to form a dovetail assembly together with the positioning members (18, 28). A shell mold for manufacturing dental prostheses characterized by the following.

9. The shell mold according to claim 8, characterized in that the complementary positioning member (36) is configured to form a slide link with the positioning members (18, 28) of the inserts (10, 20).

10. The shell mold according to claim 9, characterized in that the complementary positioning member (36) is configured to form the male portion of the dovetail assembly.

11. The shell mold according to any one of claims 8 to 10, characterized in that the complementary positioning member (36) includes a tab (36a) configured to interact with the positioning members (18, 28).

12. The shell mold according to any one of claims 8 to 11, characterized in that the complementary positioning member (36) includes an axial stopper (36b).

13. The complementary positioning member (36) includes an axial stopper (36b), The shell mold according to claim 11, characterized in that the axial stopper (36b) is formed by protruding surfaces extending perpendicularly from both sides of the tab (36a), and the complementary positioning member (36) has a T-shape.

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