DENTAL SPLINT AND METHOD FOR PRODUCING SAME

Abstract

The invention relates to a method for producing a dental splint, in particular for the treatment of craniomandibular dysfunction or for the correction of tooth misalignment, comprising a flat body made of plastics, composite and/or elastomer and having a lower face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's lower jaw, and further having an upper face that is provided with a shape configuration according to at least portions of the dental surface profile of the patient's upper jaw, the shape configuration being laterally and/or frontally-dorsally and/or vertically offset by a defined amount on the upper face relative to a position relation of optimum occlusion with respect to the shape configuration on the lower face.

Claims

1. A method for producing a dental splint, in particular for the treatment of craniomandibular dysfunction or for the correction of tooth misalignment, comprising a flat body made of plastics, composite and/or elastomer and having a lower face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's lower jaw, and an upper face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's upper jaw, the shape configuration having a defined lateral and/or frontal-dorsal and/or vertical offset amount on the upper face relative to a position relation of optimum occlusion with respect to the shape configuration on the lower face, wherein the dental surfaces of the lower jaw and the upper jaw are scanned, in the position of optimum occlusion, an occlusion position relation between the lower jaw and the upper jaw is determined by means of a position determination system, and thus an occlusion relation between the data sets of the associated scans, in a position different from the occlusion, a non-occlusion position relation between the lower jaw and the upper jaw is determined by means of a position determination system, and thus an non-occlusion relation between the data sets of the associated scans, from the data sets of the occlusion relation and the non-occlusion relation, the predetermined lateral and/or dorsal and/or vertical offset amount is determined, and at least portions of the taken scans, while taking into account the predetermined lateral and/or dorsal and/or vertical offset amount, are worked out by means of a coordinate-controlled, abrasive processing method, in particular a milling method, from a basic sheet body of the occlusion splint on the lower face or the upper face as shape configurations.

2. A method for producing a dental splint, in particular for the treatment of craniomandibular dysfunction or for the correction of tooth misalignment, comprising a flat body made of plastics, composite and/or elastomer and having a lower face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's lower jaw, and an upper face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's upper jaw, the shape configuration having a defined lateral and/or frontal-dorsal and/or vertical offset amount on the upper face relative to a position relation of optimum occlusion with respect to the shape configuration on the lower face, wherein the dental surfaces of the lower jaw and the upper jaw are directly scanned intraorally, in the position of optimum occlusion, an occlusion position relation between the lower jaw and the upper jaw is determined by means of a position determination system, and thus an occlusion relation between the data sets of the associated scans, in a position different from occlusion, a non-occlusion position relation between the lower jaw and the upper jaw is determined by means of the position determination system, and thus an non-occlusion relation between the data sets of the associated scans, from the data sets of the occlusion relation and the non-occlusion relation, the predetermined lateral and/or dorsal and/or vertical offset amount is determined, and the dental splint is built up on the basis of the scans while taking into account the predetermined lateral and/or dorsal and/or vertical offset amount by means of an additive production method at least of portions of the dental surfaces of the lower jaw and the upper jaw.

3. The method according to claim 1, wherein the occlusal splint is formed by means of a 3D plastic printing method with the complete data sets of the scans of the dental surfaces of the lower jaw and the upper jaw.

4. The method according to claim 1, wherein the dental splint is formed on an adaptation element produced on the basis of the taken scans and a thermoplastic film while taking into account the predetermined lateral and/or dorsal and/or vertical offset amount, wherein into the lower face or the upper face of the thermoplastic film, the dental surfaces of the lower jaw or the upper jaw are directly formed, and the adaptation element is fixed to the other side of the film.

5. A method for producing a dental splint, in particular for the treatment of craniomandibular dysfunction or for the correction of tooth misalignment, comprising a flat body made of plastics, composite and/or elastomer and having a lower face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's lower jaw, and an upper face that is provided with a shape configuration according to at least portions of the dental surface profile of a patient's upper jaw, the shape configuration having a defined lateral and/or frontal-dorsal and/or vertical offset amount on the upper face relative to a position relation of optimum occlusion with respect to the shape configuration on the lower face, wherein the dental surfaces of the lower jaw and the upper jaw are scanned, in the position of optimum occlusion, an occlusion position relation between the lower jaw and the upper jaw is determined by means of a position determination system, and thus an occlusion relation between the data sets of the associated scans, in a position different from the occlusion, a non-occlusion position relation between the lower jaw and the upper jaw is determined by means of the position determination system, and thus an non-occlusion relation between the data sets of the associated scans, from the data sets of the occlusion relation and the non-occlusion relation, the predetermined lateral and/or dorsal and/or vertical offset amount is determined, and at least portions of the taken scans, while taking into account the predetermined lateral and/or dorsal and/or vertical offset amount, are imprinted by means of a pressure/heat shaping process onto a thermoplastic film on the lower face or the upper face as shape configurations.

6. The method according to claim 1, wherein for determining the lateral and/or frontal-dorsal and/or vertical offset amount, a series of predetermined jaw movements, in particular opening and forward feed movements of the jaw are performed, and in each case the associated condyle relative position and/or a patient's feedback are registered and the condyle relative position, in particular interlinked with each other, are subjected to an evaluation according to a predetermined evaluation algorithm.

7. The method according to claim 6, wherein in particular opening and forward feed movements of the jaw are performed, and the associated condyle relative positions are registered, wherein the determination of the lateral and/or frontal-dorsal and/or vertical offset amount is performed when the positions of the condyles or condyle centers have been changed with respect to the initial relative position by a defined translatory amount.

8. The method according to claim 1, wherein an acoustic, visual or haptic signal is emitted by the position determination system when, during a movement of the lower jaw, the condyle position and/or the wall thickness of the splint is in or outside of a defined area or moves toward or away from it and/or has reached a predefined amount.

9. The method according to claim 1, wherein for determining the occlusion relation of optimum occlusion and/or the non-occlusion relation, a sequence of movements of predetermined jaw movements, in particular opening movements of the jaw, is registered, and the taken scans of the dental surfaces are interlinked with the detected position data for deriving respective envelopes of the dental surface positions of the lower jaw and the upper jaw.

10. The method according to claim 1, wherein the dental surfaces of the lower jaw and the upper jaw are scanned intraorally, and an occlusion relation between the data sets of the intraoral scans of the upper jaw and the lower jaw is determined.

11. A dental splint produced by a method according to claim 1.

12. The dental splint according to claim 11, formed as a lower jaw splint for being fixed onto the patients' lower jaw, wherein the shape configuration on the lower face substantially is contoured according to the total dental surface profile of the patients' lower jaw.

13. The dental splint according to claim 11, formed as an upper jaw splint for being fixed onto the patients' upper jaw, wherein the shape configuration on the lower face substantially is contoured according to the total dental surface profile of the patients' upper jaw.

14. The dental splint according to claim 11, substantially formed from rigid plastic with a shape configuration milled into the lower face and the upper face.

15. The dental splint according to claim 11, manufactured from a fused thermoplastic powder or granulate or light-curing liquid polymers, wherein the shape configurations on the lower face or the upper face are formed by additive molding.

16. The dental splint according to claim 11, manufactured from a thermoplastic film, wherein the shape configurations on the lower face or the upper face are formed by a pressure/heat shaping process and/or by means of an adaptation element placed upon and manufactured by a milling process or additive molding onto at least one of the lower face and the upper face.

17. A set of dental splints according to claim 11, wherein the occlusal splints of the set have different lateral and/or frontal-dorsal and/or vertical offset amounts with respect to the position relation of optimum occlusion and/or have a different thickness at least in portions.

Description

[0040] Advantages and expediencies of the invention incidentally will result from the following description of an exemplary embodiment with reference to the Figures. Shown are in:

[0041] FIGS. 1A-1E schematic representations of a patient's dentation in the state of optimum occlusion, without a dental splint (FIG. 1A), on the one hand, and having different dental splints manufactured according to the invention (FIGS. 1B-1E), on the other hand,

[0042] FIG. 2 a principal sketch (functional block diagram) of a system for obtaining intraoral scans of the dental surfaces and associated position data,

[0043] FIG. 3 a perspective representation of a para-occlusal bracket to be inserted in such a system, and

[0044] FIGS. 4A to 4D sketch-like representations of steps for producing a dental splint according to the invention.

[0045] For explaining substantial aspects of a dental splint produced according to the invention, FIGS. 1A-1E represent schematic representations of the upper jaw OK and the lower jaw UK of a patient in whom a splint therapy with dental splints is implemented for treating functional disorders of the jaw joint.

[0046] In this case, FIG. 1A shows the state of optimum occlusion, consequently of the closing engagement of the dental surfaces SOK of the upper jaw and the dental surfaces SUK of the lower jaw. If, from a clinical point of view, this position is not advantageous, e.g. painful, the jaw joint is repositioned into a therapeutically desired position by means of a dental splint. Depending on the patient-specific functional disorder and in particular also depending on the pain feelings of the patient, a plurality of options regularly exists for this purpose, between which can also be “switched” during the therapeutic process in case of demand.

[0047] FIG. 1B, for example, shows the jaw position with an inserted dental splint 1, a so-called distraction splint, which slightly shifts the lower jaw (in parallel to the occlusion plane) downwards. Apart from the fact that the dental splint 1 of course also has a certain thickness, the position of a molding configuration 2 on the upper face corresponding to a large extent to the dental surface profile of the upper jaw OK, corresponds with respect to the molding configuration 3 on the lower face to the position relation of optimum occlusion.

[0048] FIG. 1C shows another dental splint 1a, which can be likewise referred to as a distraction splint, but which displaces the lower jaw in the rear area further downwards than the dental splint 1 of FIG. 1B. Consequently, here exists a vertical offset amount in the rear area of the splint 1a between the molding configuration 2a on the upper face and the molding configuration 3a on the lower face. Since the splint 1a basically causes the molding configuration to be tilted with respect to the position of optimum occlusion, there is also a (small) frontal-dorsal offset amount.

[0049] FIG. 1D schematically shows the jaw position with another inserted dental splint 1b, which can be referred to as a retrusion/distraction splint and slightly shifts the lower jaw downwards/rearwards. With respect to the position of optimum occlusion (FIG. 1A), there is both a vertical and a frontal-dorsal offset amount between the molding configuration 2b on the upper face and the molding configuration 3b on the lower face of the splint 1b.

[0050] FIG. 1E shows a dental splint 1c as a further variant, which can be referred to as a protrusion splint and slightly shifts the lower jaw forwards. Between the molding configuration 2c on the upper face and the molding configuration 3c on the lower face of the dental splint 1c, consequently there is a significant frontal-dorsal offset amount, but no substantial vertical offset amount.

[0051] Apart from the configurations shown here by way of example, there are numerous other configurations, and basically dental splints can also be therapeutically reasonable, in which between the shape configurations on the upper face and the lower face exclusively or in addition to a vertical or frontal-dorsal offset amount, a lateral (right-left) offset amount is present so that the lower jaw teeth are correspondingly laterally shifted with respect to the upper jaw teeth.

[0052] These therapeutical measures may in particular be combined with the measure to simultaneously correct orthodontic false positions of teeth and to exert a continuous pressure upon the teeth so as to thereby achieve an offset up to a desired tooth position.

[0053] The dental splints schematically shown in FIGS. 1B-1E may in each case be provided individually as therapy aids or a set of dental splints (and, if necessary, other and/or further ones) can be formed from them.

[0054] FIG. 2 shows as a principal sketch essential parts of a system 100 for the moving picture detection/representation of a patient's dentition while using a special para-occlusal bracket 10 as shown in FIG. 3 in a sketch-like manner.

[0055] The system comprises a position signal detection unit 105 and a position calculation unit 107, which evaluate the position signals from a position marker part 15 of the bracket 10 in its state inserted in the mouth of a patient. The result is a position data set of the bracket which exactly represents that position of the bracket with respect to a space-fixed coordinate system in which scans of the lower jaw and/or the upper jaw had been generated.

[0056] The dental surfaces are optically detected by means of an intraoral scanner 109 in a defined partial area of the total extension of the bracket by the detection zone 109a of the scanner, and the associated image data set is stored. It comprises image data of the markers (not shown completely in this Figure) at the edges of the coupling spoon, which are situated within the detection zone 109a. From a data base 11, an image data set previously generated and stored of the entire bracket is loaded into a comparing processing unit 113 and subjected to a comparing processing with the image data set of the detection zone 109a there. In this case, the markers situated within the detection zone are identified as a partial amount of all of the markers provided in the coupling spoon, and on the basis of this identification, the detection zone 109a and consequently the impressions 101a situated within it can be precisely allocated in position with respect to the bracket 10.

[0057] Together with the associated (relative) position coordinates, the image obtained in the detection zone 109a arrives in an overall picture synthesis stage 115, in which it is processed together with the images (partial images) obtained by the scanner in other partial areas—into a dental surface overall picture while taking the relative position coordinates as a basis.

[0058] Both the partial image provided with the relative position coordinates and the dental surface overall picture can be referred to a space-fixed coordinate system by means of the (absolute) position coordinates of the bite fork obtained within the position calculation unit 107. In the Figure, this is represented for the dental surface overall picture that is provided at the output of the overall picture synthesis stage 115. Together with the position coordinates available at the output of the position calculation unit 107 it is subjected to a combining processing in an image/coordinate allocation stage 117. The result is a dental surface overall picture absolutely true to coordinates which can be used in the method according to the invention (as a control data set) but also for visualizations of dental diagnostic findings or other measures.

[0059] FIG. 3 shows the para-occlusal bracket 10 set frontally upon the entire tooth row of a patient's lower jaw UK, which is fixed to the teeth by means of a preferably elastic or hard elastic, sufficiently adhesive registration material or adhesive 13. In a central position of the bracket basic body 11, a mounting sleeve 11a protruding frontwards at a right angle is arranged thereon, which is adaptable to a mounting pin 15a of the sensor part 15 to be attached to the bracket basic body 11. In this realization represented in a simplified manner, the attachment is performed by pushing the pin 15a into the sleeve 11a and by fixing the pin within the sleeve in a friction fit (or form-fit) manner. Appropriately, in practice, the pin-sleeve arrangement is provided with moldings for specifying a defined angular position of the sensor part 15 with respect to the bracket basic body 11 (such as a tongue and groove arrangement), which, however, is not shown in the Figure.

[0060] At the upper face and front face of the bracket basic body 11, various markers 11b are provided, which are easily readable for an intraoral scanner and are easily distinguishable in evaluating a scan. The markers, represented here as different symbols, but can also be formed to be colored or as elevations/depressions or the like, allow portions of the bracket basic body 11 taken in a scan and thus the respectively mapped teeth to be unequivocally allocated to a position with respect to the lower jaw.

[0061] The bracket basic body 11 is produced as a molded part, such as a plastic injection molded part (such as of polyamide or ABS or another physiologically harmless polymer) but also as a cast part of metal (e.g. from an aluminum alloy). It can be a plastic molded part with an inserted metal reinforcement or another kind of molded part. The molded part can be partially or in total consist of a transparent material allowing it to be received on dental surfaces simultaneously with the markings.

[0062] The measurement sensor part 15 is represented in FIG. 3 merely in a symbolic manner; it may include an arrangement (known per se) of transmitters or sensors or reflectors of an ultrasound position determination system.

[0063] As already noted further above, the system explained above may also be used to record moving picture records (or corresponding data sets of the dental surfaces of the lower jaw and upper jaw that are true to their coordinates) in case of the patient's different dentition movements and to obtain envelopes of the motion curves from this, that are finally used for producing the shape configurations on the upper face and lower face of the occlusion splint.

[0064] The consideration of predetermined offset amounts may comprise, as likewise already noted, a step of a feedback delivered by the patient with respect to pain-afflicted or pain-free relative positions, wherein here, in this case, exact position data or coordinate-precise image data sets can be allocated to the patient's feedback.

[0065] FIGS. 4A-4 D show a greatly simplified representation of a human upper jaw and lower jaw including a jaw joint, wherein in FIGS. 4A to 4C three different lower jaw positions including a corresponding tooth situation and condyle position are represented.

[0066] The position signal detection unit 105 is in each case attached to the lower jaw teeth via a corresponding support 11. As described further above, the detection unit 105 can include optical, acoustical, magnetic or initial sensors and possibly still requires a stationary transmitting and receiving unit (not represented here) that is attached to the head or upper jaw.

[0067] FIG. 4A shows the teeth of the upper jaw and lower jaw in occlusion, wherein the condyle joint head 6 is located in the rear area of the joint recess (fossa mandibularis) 5. The center of the condyles 4 may be detected by the position measurement system, for example, via a rotational movement (as shown in FIG. 4B) and be used as the joint focus or joint center for the further calculations of the condyle positions.

[0068] The condyle positions represented in both of the FIGS. 4A and 4B may be quite undesired and also come about by abrasion of the teeth. As shown in FIG. 4B, a retention of the joint heads in the rear position may occur during an opening movement. In this position, a splint that is not effective to the patient would be possibly created. It is therefore preferred to carry out a feedback control of the condyle position in the construction of dental splints by means of the method according to the invention.

[0069] FIG. 4C shows a possibly desired condyle position as well as a tooth situation which would come about with a dental splint having a desired wall thickness, wherein the condyle center moves forwards by a translatory amount and a joint gap gas formed in the rear area. For determining a defined and optimum splint wall thickness, in this case as well, an acoustic, visual or haptic feedback method is proposed.

[0070] FIG. 4D shows a dental splint 1 manufactured based on the position data determined in this situation. Here, it is proposed in particular, not to generate only one dental splint (as represented), but a set of splints having different splint wall thicknesses.

[0071] The implementation of the invention is not restricted to the aspects and explained examples emphasized above, but is likewise possible in a great number of modifications which are in the scope of expertise action.