WO2014170111A1

WO2014170111A1 - Method for producing a precision model of a set of teeth for producing/adapting a dental prosthesis

Info

Publication number: WO2014170111A1
Application number: PCT/EP2014/056203
Authority: WO
Inventors: Steffen Puscher
Original assignee: Vhf Camfacture Ag
Priority date: 2013-04-18
Filing date: 2014-03-27
Publication date: 2014-10-23
Also published as: DE102013207048A1

Abstract

The invention relates to a method for producing a precision model (1) of a set of teeth. According to the method, a digital actual state of a set of teeth (3) is generated; a raw model (7) consisting of a base (8) and a material bead (9) attached thereon is produced; a preform of the actual state of the set of teeth (3) is produced from the raw model (7); and the preform is subsequently removed from the base (8) and the at least one tooth stump (5') is separated from the preform and returned onto the base (8), or the at least one tooth stump (5') is separated from the remaining teeth (4') and the teeth are removed from the base (8), the at least one preform tooth stump (5') fixed on the base (8) by means of the positioning elements (10) is completely processed, and the remaining teeth (4') are placed back onto the base (8) such that a precision model (1) of the set of teeth (3) is provided in order to produce the dental prosthesis (2).

Description

Method for producing a precision denture model for the manufacture / adaptation of a dental prosthesis

The present invention relates to a method for producing a precision denture model for the production / adaptation of a dental prosthesis. The invention also relates to a method for producing or adapting a dental prosthesis.

Due to the ever-increasing life expectancy of people, the subject of dentures is becoming increasingly important. The precision in the manufacture of the dental prosthesis has been increased considerably in recent years due to the increasing digitization, in particular the manufacture of crowns and bridges, ie in general a dental prosthesis, which must be adapted to existing teeth, particularly high demands. For the production of a bridge or a crown, an impression of the existing dentition with the tooth stump to be crowned was taken so far and from this a model was cast. By means of a so-called intra-oral scanner also a digitized model of the actual condition of the dentition could be generated or scanned. After a mere scan of the dentition, a physical model of the dentition was then milled by means of a multi-axis milling machine, to which the denture to be produced was adapted. However, particularly in the area of the tooth stump to be crowned, a particularly exact fabrication of the physical denture model is required so that the tooth stumps are milled separately and thus produced with high precision. These now very precise tooth stumps were inserted through corresponding holes back into the physical model of the dentition, which always had the difficulty when inserting the tooth stump in insert the correct height and fix. Already deviations of a few hundredths of a millimeter can produce the crown to be produced after this used tooth crown with respect to the opposing teeth (antagonists) and thereby trigger a feeling of chewing. A high-precision machining of the tooth stump within the physical model was not possible due to the teeth surrounding the tooth stump and the associated limited accessibility, so that the separate production of the tooth stump and its subsequent insertion into a bore arranged on the physical model instead of the tooth stump were essential. The known manufacturing methods for a denture model for the manufacture or adaptation of a dental prosthesis were thus complex and in terms of accuracy despite the highest effort only partially satisfactory, so that many patients complained about corresponding misperceptions and the dentures had to be reworked if necessary again.

The present invention is therefore concerned with the problem of providing an improved method for producing a high-precision denture model for the production / adaptation of a dental prosthesis, by means of which a rational, cost-effective and also extremely precise production of a precision denture model and thus also a very precise manufacture or adaptation the denture is possible.

This problem is solved according to the invention by the subject matters of the independent claims. Advantageous embodiments are the subject of the dependent claims.

The present invention is based on the general idea to significantly improve a denture model for the production / adaptation of a dental prosthesis with regard to its accuracy or realism, especially in the range of tooth stumps to be covered by the machined tooth stumps no longer manufactured separately and then via corresponding holes in the overall but remain during production in the actual denture model and at the same time the surrounding teeth of the denture model, be removed, resulting in a much improved accessibility to the precisely machined tooth stumps. In the method according to the invention, in a first method step, a digital actual state of a denture with the teeth contained therein and with at least one dental stump to be provided with the dental prosthesis, for example, to be crowned, is generated or received. Subsequently, a raw material model consisting of a carrier plate and a material bead applied thereon in the form of a row of teeth is produced, with pin-like positioning elements projecting in the direction of the material bead and engaging in this positioning element being provided with an unambiguous relative position between the carrier plate and the material bead and thus between the carrier plate and the later dentition model. Using the digitized data of the actual condition of the bit, a preform of the actual condition of the bit with the teeth and the at least one tooth stump is now produced from the raw model, that is to say more precisely from the cured material bead of the raw model. This is done for example by means of a known multi-axis precision milling machine. Subsequently, alternatively, the preform of the milled bit can be removed from the carrier plate, the at least one tooth stump cut out of the preform and reset to the carrier plate or the at least one tooth stump is separated from the rest of the material bead, that is the other teeth, so that only this remaining material bead with the teeth is removed from the support plate. Both alternative embodiments allow a farther to be machined tooth stump on the support plate without the teeth surrounding this tooth stump or tooth stumps. The sole arrangement of the at least one tooth stump on the support plate, the accessibility of the at least one tooth stump to be machined is significantly improved, since a milling tool is not hindered in particular by the surrounding teeth. In the first alternative, the entire preform of the bit removed from the carrier plate becomes the at least one tooth stump cut out and then reset back to the support plate, the positioning ensure that it retains its original position, especially in terms of alignment and height again exactly. In the second alternative, the at least one tooth stump to be machined is not removed at all from the carrier plate, so that it also retains its original exact position. In an adjoining method step, the at least one tooth stump of the preform fixed on the carrier plate by means of the positioning elements is then finished, in particular finished milled and / or ground. If this process step is completed, the remaining teeth can be placed back on the support plate and thereby take over the positioning again their original position exactly, so that now a highly accurate Präzisionsgebissmodell the teeth for the preparation / adjustment of the denture is present, in which in particular Tooth stump has the exact height compared to the surrounding teeth, which could not be guaranteed in the previous manufacturing process in which the tooth stump was made separately and then attached via a hole in the denture model. The method according to the invention thus represents a considerable improvement which, in particular, minimizes or at best even completely eliminates the discomfort of the dental prosthesis wearer which is produced in previous methods.

In an advantageous development of the solution according to the invention, the digital actual condition of the dentition is recorded by means of an intra-oral scanner. Such a direct digital recording of the dentition of a patient allows an immediate presence of a digital data set of the dentition and minimizes in particular the influences or fluctuations occurring in a previous conventional impression taking, in particular in the field of the material and the skill of the dentist. The inclusion of a digital impression of the dentition is also much more pleasant for the patient than the conventional impression taking, whereby an increase in comfort for the patient can be achieved. Of course, alternatively, a conventional Ab- pressure of the dentition taken and from this the digital actual state of the dentition are generated.

For the production of the raw model, the initially soft material bead in the form of a U-shaped row of teeth is expediently applied to the carrier plate, the positioning elements being pressed into the material bead. The material bead can be made of a thermosetting plastic-gypsum mixture and has due to the depressed in the material bead positioning after curing a clear relative position to the support plate. The positioning elements are preferably conical, that is tapered to a free end, whereby the material bead, for example, the preform of the actual state of the bit removed from the support plate and can be placed in the same way again exactly on the support plate. Preferably, two parallel rows of positioning elements are provided on the carrier plate, wherein the positioning elements of the two rows are arranged offset from one another, which enables angular and exact positioning or resetting of the one segment onto the carrier plate, particularly when the material bead is separated into individual segments. The carrier plate is preferably designed as a reusable plastic model.

The present invention is further based on the general idea of a method for the manufacture or adaptation of a dental prosthesis using a precision denture model manufactured according to the previously described method. In the method according to the invention, a separately manufactured dental prosthesis, for example a bridge or a crown, is then placed on the at least one finished tooth stump of the precision dental model and arranged on the carrier plate and adapted to the surrounding teeth. Of course, an adaptation of the separately manufactured dental prosthesis on the dental stump supporting this denture is possible. By means of the method described in the previous paragraphs and the method according to the invention It is now possible to precisely adjust the dental prosthesis, in particular with regard to its height, since the precision dentition model represents an identical image of the real dentition, that is to say of the actual condition of the dentition of the patient. Due to the high precision of the precision denture model, a high-precision adaptation of the dental prosthesis is possible, which is manifested by an increased wearing comfort and an improved longevity of the dental prosthesis.

In a further advantageous embodiment of the method according to the invention, the precision dentition model together with the tooth replacement is inserted into an articulator and the dental prosthesis therein is adapted to the antagonist (s). Such an articulator is a device for simulating the temporomandibular joint movement, for which purpose the precision teeth model produced by the method according to the invention is mounted in occlusion in the articulator. Subsequently, the articulator is able to simulate the movement of the jaws to each other, which is essential for the preparation of dentures.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

A preferred embodiment of the invention is illustrated in the drawings and will be explained in more detail in the following description.

In each case show schematically: 1 shows the recording of a digital actual state by means of an intra-oral scanner,

2a is a carrier plate with positioning,

2b is a representation as in Fig. 2a, but with applied bead of material,

Fig. 3a is a preform of the actual state of the dent with herausgelöstem

Tooth stump,

3b is a view as in Fig. 3a, but in a view obliquely from below,

3c is an oblique view from below of the separated tooth stump,

FIG. 3d the tooth stump in a state placed on the carrier plate, FIG.

Fig. 4a, applied to the carrier plate preform of the actual state of

dentition

4b is a view as in Fig. 4a, but with teeth removed,

5 shows a representation of a precision dentition model of the denture,

6 shows the precision denture model used in an articulator.

Corresponding to FIGS. 1 to 5, a method according to the invention for producing a precision denture model 1 for the production / adaptation of a dental prosthesis 2 (see FIG. 6) is described. To produce the precision dentition model 1, a digital actual state of a denture 3 with teeth 4 and at least one with is now in a first method step according to FIG the dental prosthesis 2 to be provided tooth stump 5 generated / recorded. For this purpose, for example, an intraocular scanner 6 is used, which directly supplies a digitized form of the dentition 3 together with teeth 4 and at least one tooth stump 5. Alternatively, of course, first of all a conventional impression of the bit 3 can be taken and from this the digital actual state of the bit 3 can be generated.

When carrying out the method according to the invention, a raw model 7 (compare FIG. 2b) is now to be provided, which consists essentially of a carrier plate 8 and a material bead 9 applied thereto in the form of a row of teeth. On the support plate 8 pin-like, projecting in the direction of the bead of material 9 and penetrating into this positioning elements 10 are arranged, which cause a clear relative position between the support plate 8 and the cured material bead 9. In this case, two parallel rows of positioning elements 10 are provided, wherein the individual positioning elements 10 of the two rows are arranged offset from one another in order to be able to fix individual segments of a material bead 9 to be sliced segment-like in later method steps. The positioning elements 10 are conical, that is, tapering towards its free end, so that the hardened material bead 9 can be removed more easily and put back in the same position. From this raw model 7, a preform of the actual state of the bit 3 with teeth 4 'and the at least one tooth stump 5' is now produced, for example by means of a multi-axis milling machine. Teeth 4 'and tooth stump 5' denote components of the precision dentition model 1, whereas tooth 4 and tooth stump 5 denote the natural dentition components in the mouth of the patient.

Particularly in the region of the at least one tooth stump 5 ', an identical image of the tooth stump 5 must be produced for exact adaptation of the tooth replacement 2, for which purpose the tooth stump 5' additionally has to be finely machined in comparison to the other teeth 4 '. This may alternatively be in two Process steps take place, wherein the first according to the figures 3a-d and the alternative thereto according to the figures 4a and b are shown.

In the first alternative, the preform of the dentition 3 ', that is, with teeth 4' and the at least one tooth stump 5 ', removed from the support plate 8, the at least one tooth stump 5' separated out of the preform and individually reset to the support plate 8 , This is shown in FIG. 3d. Due to the singular arrangement of only the tooth stump 5 'without the surrounding teeth 4' on the support plate 8, the tooth stump 5 'for further processing, for example by a milling machine, particularly easily accessible from all sides.

Alternatively, it is also conceivable that the at least one tooth stump 5 'of the remaining material bead 9, that is separated from the surrounding teeth 4', then the remaining material bead 9 with the teeth 4 'is removed from the support plate 8, so that also In this case, only the tooth stump 5 'singularly remains on the support plate 8 and thereby can be better edited. Generally applies to all embodiments in the past and in the following is often spoken only by a tooth stump 5 ', of course, a plurality of such tooth stumps 5' can be provided. If the tooth stump 5 'to be further processed is arranged individually on the carrier plate 8 and fixed by means of the positioning elements 10, then it can be finished, in particular milled and / or ground. Subsequently, the remaining teeth 4 'are again placed on the support plate 8 and take over the positioning elements 10 back to their original position exactly, so that now an exact Präzisionsgebissmodell 1 of the bit 3 for the production / adaptation of the dental prosthesis 2 is present. Due to the positioning elements 10, which press into the next soft material bead 9, the material bead 9 can later be segmented in the cured state, it being possible, all segments due to the positioning elements 10 of the support plate 8 and, if necessary, again exactly with respect to their original position on the carrier plate 8 to position. For example, a hardening plastic-gypsum mixture can be used for the material bead 9.

In theory, it is also conceivable that the tooth stump 5 'together with the surrounding teeth 4' completely finished to milling, without the tooth stump 5 'or the teeth 4' stand out from the carrier 8, if the teeth stump 5 'surrounding teeth 4' processing of the tooth stump 5 'does not hinder. This is possible, for example, if the tooth stump 5 'can be reached so far that it can be completely milled. In this case one would separate the tooth stump 5 'only when this is completely finished milled.

Compared to previously known manufacturing method for a denture model in which the tooth stump was prepared separately and then inserted through a introduced into the denture hole in this, the inventive method is characterized in that now the tooth stump 5 'in exact height to the surrounding Teeth 4 'of the precision denture model 1 is arranged. This was not possible in the conventional method or only under extremely difficult conditions, with a non-exact arrangement of the tooth stump in the conventional method of production was always responsible for discomfort of the patient, since even deviations of a few hundredths of a millimeter punctate edition of the tooth replacement on an opposing tooth ( Antagonists) and thereby cause tooth and headache. With the method according to the invention, this can be ruled out, since due to the positioning elements 10 and the individual arrangement of the tooth stub 5 'during the finishing process on the carrier plate 8, this is not changed at all in terms of its height.

The precision denture model 1 of the dentition 3 produced in this way is now used to adapt the dental prosthesis 2, for example a bridge or a crown, with the separately prepared dental prosthesis 2 being placed on the at least finished tooth stump 5 'of the precision denture model 1 and attached to the surrounding teeth 4 'is adjusted. Subsequently, the precision dentition model 1 together with dental prosthesis 2 can be inserted into an articulator 11 (see FIG. 6) and the dental prosthesis 2 can be adapted therein to the antagonist (s) 4, ie the opposite teeth 4.

With the method according to the invention a cost-effective and at the same time efficient, but on the other hand also highly precise preparation / adaptation of dental prosthesis 2 is thus possible.

Claims

claims

Method for producing a precision denture model (1) for the manufacture / adaptation of a dental prosthesis (2), in which

a digital actual state of a denture (3) with teeth (4) and at least one tooth stump (5) to be supplemented with the dental prosthesis (2) is generated / recorded,

a raw model (7) which consists of a carrier plate (8) and a material bead (9) applied thereon in the form of a row of teeth is produced, wherein pin-like positioning elements projecting in the direction of the material bead (9) are mounted on the carrier plate (8). 10) are provided which force a clear relative position between carrier plate (8) and material bead (9),

a preform of the actual state of the bit (3) with teeth (4 ') and the at least one tooth stump (5') is produced from the raw model (7) and subsequently

the preform is removed from the carrier plate (8), the at least one tooth stump (5 ') is separated out of the preform and returned to the carrier plate (8), or

the at least one tooth stump (5 ') is separated from the remaining material bead (9), that is to say the remaining teeth (4'), and the remaining teeth (4 ') are removed from the carrier plate (8),

the at least one tooth stump (5 ') of the preform fixed on the carrier plate (8) by means of the positioning elements (10) is finished, in particular milled and / or ground,

the remaining teeth (4 ') are placed back on the support plate (8) and on the positioning (10) their original position again exactly take, so that now an exact Präzisionsgebissmodell (1) of the bit (3) for the production / adjustment of the dental prosthesis (2) is present.

2. The method according to claim 1,

characterized in that

the digital actual state of the bit (3) is recorded by means of an intra-oral scanner (6), or

first taken an impression of the bit (3) and from this the digital actual state of the bit (3) is generated.

3. The method according to claim 1 or 2,

characterized in that

the first still soft material bead (9) in the form of a row of teeth on the support plate (8) is applied, wherein the positioning elements (10) press into the material bead (9).

4. The method according to any one of claims 1 to 3,

characterized in that

the preform of the actual condition of the bit (3) is milled, ground or lasered.

5. The method according to any one of claims 1 to 4,

characterized in that

the preform of the at least one tooth stump (5 ') is finished without the surrounding teeth (4') and thereby significantly more easily accessible.

6. The method according to any one of claims 1 to 5,

characterized in that

for the material bead (9) a hardening plastic-gypsum mixture is used.

7. The method according to any one of claims 1 to 6,

characterized in that

the material bead (9) is held over two parallel rows of positioning elements (10), wherein the positioning elements (10) of the two rows are arranged offset from one another.

8. A method for producing / adapting a dental prosthesis (2), in which a precision dentition model (1) of the dentition (3) produced according to one of claims 1 to 7 is used, and in which the at least one finished tooth stump (5 ') of the Precision denture model (1) of the separately manufactured dentures (2), for example, a bridge or a crown, placed and adapted to the surrounding teeth (4 ').

9. The method according to claim 8,

characterized in that

the precision denture model (1) together with dental prosthesis (2) is inserted into an articulator (11) and the dental prosthesis (2) therein is adapted to the antagonist (s).