DENTAL AUXILIARY STRUCTURE AND MANUFACTURING METHOD

Abstract

It is described an auxiliary structure (240, 440, 540) for treatment of at least one tooth (123) of an upper jaw (100) and/or lower jaw (120), the auxiliary structure comprising: a body (241), in particular comprising a plastic material; the body having a lower surface (233) and an upper surface (235), which are defined based on a lower border (665, 765) of a lower volume (666) occupied by lower teeth of the lower jaw in a bite state and an upper border of an upper volume occupied by upper teeth of the upper jaw in the bite state, wherein the lower surface (233) and/or the upper surface (235) comprises at least one recess (257) with respect to the lower border and/or the upper border, respectively, and/or a common annular edge (247, 251, 253, 255) limiting a through hole (249, 252, 254, 256) through the body (241).

Claims

1. Auxiliary structure (240, 440, 540) for treatment of at least one tooth (123) of an upper jaw (100) and/or lower jaw (120), the auxiliary structure comprising: a body (241), in particular comprising a plastic material; the body having a lower surface (233) and an upper surface (235), which are defined based on a lower border (665, 765) of a lower volume (666) occupied by lower teeth of the lower jaw in a bite state and an upper border of an upper volume occupied by upper teeth of the upper jaw in the bite state; wherein the lower surface (233) and/or the upper surface (235) comprises at least one recess (257) with respect to the lower border and/or the upper border, respectively, and/or a common annular edge (247, 251, 253, 255) limiting a through hole (249, 252, 254, 256) through the body (241).

2. Auxiliary structure according to claim 1, wherein the through hole (249) is in a region of the body where the lower border (665) coincides with the upper border, thereby defining a portion of a tooth of the upper jaw and/or a tooth of the lower jaw to be diminished for improving the chewing motion, wherein the annular edge of the through hole is in particular visually and/or hapticly marked, in particular using color and/or texture and/or a recognizable surface property that differs when compared to non-marked regions of the body.

3. Auxiliary structure according to claim 1, wherein the recess (257) defines a volume portion to accompany supplement material (458) to be adhered to a tooth (123) that defined a corresponding area of the lower border or the upper border.

4. Auxiliary structure according to claim 1, wherein the recess (257) is in a lateral region where the upper border and the lower border have a relative distance greater than a threshold, wherein a visual and/or haptic indication at or close to the recess indicating the recess is provided.

5. Auxiliary structure according to claim 1, wherein the recess (257, 457) is adapted to temporally accompany a pre-fabricated solid supplement to be adhered to one of the teeth (123).

6. Auxiliary structure according to claim 1, wherein a filling material duct (461) in communication with the recess (457) is formed in the body (441), the filling material duct leading from the upper surface (435) to the lower surface (433) of the auxiliary structure (440) comprising the recess (457), for allowing excess liquid or viscous filling material (458) to be expelled via the filling material duct (461) to the surface of the auxiliary structure different form the surface of the auxiliary structure at which the recess is arranged.

7. Auxiliary structure according to claim 6, wherein the filling material duct (461) has a lateral extension (d1, d2) that is lower close to the recess than far from the recess, to define a predetermined breaking point (463), when the auxiliary structure is withdrawn after the filling material has solidified or has been adhered to the tooth.

8. Auxiliary structure according to claim 1, wherein the lower border limits a lower volume occupied by the lower teeth during a chewing motion and the upper border limits an upper volume occupied by the upper teeth during the chewing motion.

9. Auxiliary structure according to claim 1, wherein the bite state or the chewing motion is a state or motion modified from an original bite state or chewing motion by repositioning a bite/lower jaw rotation axis.

10. Method for manufacturing an auxiliary structure (240, 440, 540) for dental treatment, the method comprising: providing a 3D model (100, 120) of an upper jaw including plural upper teeth and a lower jaw including plural lower teeth; using the 3D model to define a lower border (665) of a lower volume (666) occupied by the lower teeth (123) in a bite state and an upper border of an upper volume occupied by the upper teeth (103) in the bite state; defining a geometry of the auxiliary structure (240, 440, 540) based on the lower border and the upper border, thereby providing, in the auxiliary structure, at least one recess (257) with respect to the lower border and/or the upper border, and/or an annular edge (247, 547) common to an upper surface and a lower surface of the auxiliary structure, the common edge limiting a through hole (249, 549) through the auxiliary structure (240, 540).

11. Method according to claim 10, further comprising: modifying the 3D model by repositioning the lower jaw relative to the upper jaw in particular including repositioning a lower jaw rotation axis; using the modified 3D model to define a modified lower border (765) and a modified upper border; and defining a geometry of the auxiliary structure based on the modified lower border and the modified upper border.

12. Method according to claim 10, further comprising: manufacturing the auxiliary structure (240, 540) using, in particular thermoplastic and/or thermosetting, material, in particular composite material including plastic, wherein the material is successively supplied to the growing structure using a 3D-printer to which the defined geometry is supplied, wherein the material in particular includes fibre material.

13. Method according to claim 10, further comprising: acquiring, at plural time instances during a chewing motion using the teeth, position data representing positions of the upper teeth relative to positions of the lower teeth; using/combining the position data to obtain another lower border (665) of another lower volume occupied by the lower teeth during the chewing motion and another upper border of another upper volume occupied by the upper teeth during the chewing motion; defining another geometry of the auxiliary structure based on the other lower border (665) and the other upper border.

14. Method according to claim 13, wherein the acquiring the position data in particular comprises: attaching plural position sensors at the lower jaw and a body portion which is fix relative to the upper jaw, acquiring measurement signals, during the chewing motion, from the plural position sensors, wherein at least one of the position sensors comprises In particular at least one acceleration sensor.

15. Method of producing a dental supplement for at least one tooth using an auxiliary structure according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIGS. 1a, 1b and 1c schematically illustrate perspective views of an upper jaw, a lower jaw, and a model of the assembled upper jaw and the lower jaw;

[0038] FIGS. 2a, 2b schematically illustrate an auxiliary structure for treatment of at least one tooth together with an upper and a lower jaw according to an embodiment of the present invention;

[0039] FIG. 3 schematically illustrates an auxiliary structure for treatment of at least one tooth according to an embodiment of the present invention;

[0040] FIG. 4 schematically illustrates in a cross-sectional side view an auxiliary structure, a tooth and a filling/supplement according to an embodiment of the present invention,

[0041] FIG. 5 schematically illustrates in a cross-sectional side view an auxiliary structure for treatment of at least one tooth according to an embodiment of the present invention;

[0042] FIG. 6 schematically illustrates in a side view several states during a chewing motion of a tooth employed for defining a geometry of an auxiliary structure according to an embodiment of the present invention; and

[0043] FIG. 7 schematically illustrates procedural steps for lowering a lower jaw rotation axis employed for manufacturing an auxiliary structure according to an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0044] It should be noted that elements or features similar in structure and/or function are in different embodiments designated with reference signs differing only in the first digit. Thus, when a particular feature is not described in detail with reference to a particular embodiment, a description of this respective feature may be taken from the explanation of another embodiment.

[0045] FIGS. 1a and 1b schematically illustrate in perspective views an upper jaw 100 including a teethridge 101 and plural upper teeth 103 and a lower jaw 120 including a teethridge 121 and plural lower teeth 123. One or more of the upper teeth 103 or the lower teeth 123 may require treatment, such as one or more supplements, such as a crown, an inlay, an onlay or one or more removal procedures for removing one or more portions of the teeth 103, 123. Restoration or modification of the teeth 103, 123 may be required due to structure loss of one of the teeth or potentially due to caries or a malposition or defective position in a bite state, such as for example illustrated in FIG. 1c. A defective position or malpositioning may occur during a single bite state or during a chewing motion including several bite states.

[0046] During chewing the lower jaw 120 may rotate around a rotation axis 125 which may represent an original rotation axis. A chewing motion may comprise a complicated motion including rotation, translation, in particular translation comprising vertical components and also lateral or side components. In the bite state or during the chewing motion portions of one or more teeth 103, 123 may interfere with, i.e. may impede or obstruct or hinder, the natural chewing motion or may interfere with at least one bite state. Furthermore, extensive void volumes between opposing teeth may be present during the bite state or during an entire chewing motion. The void volumes between opposing teeth may also impair biting or may impair the chewing motion or function.

[0047] Thus, for improving a bite state and/or an entire chewing motion it may be desired to remove portions of particular teeth and/or add supplements or additional material to other portions of (other) teeth. Embodiments of the present invention provide a dental auxiliary structure, such as illustrated in FIGS. 2a, 2b, 3, 4, 5, which may help or aid the dentist for performing a treatment of the teeth 103, 123 to achieve the afore-mentioned goals.

[0048] FIG. 2a schematically illustrates a precursor 230 of an auxiliary structure according to an embodiment of the present invention together with the lower jaw 120 and the lower teeth 123. The precursor 230 of the auxiliary structure comprises a body 231 which comprises plastic material. The body of the precursor 230 has a lower surface 243 and an upper surface 245 which correspond to a lower border of a lower volume occupied by the lower teeth 123 in a bite state and an upper border of an upper volume occupied by the upper teeth 103 in the bite state. Thus, the precursor 230 has a lower surface 243 and an upper surface 245 that substantially corresponds or equals a surface geometry of a dental imprint or dental cast as it has for example been obtained by asking the patient to adopt a bite state when viscous material is placed between the upper jaw 100 and the lower jaw 120.

[0049] FIG. 2b schematically illustrates a dental auxiliary structure 240 (placed onto lower teeth) according to an embodiment of the present invention as derived from the precursor auxiliary structure 230 as illustrated in FIG. 2a. FIG. 3 schematically illustrates the dental auxiliary structure 240 according to an embodiment of the present invention taken out of the mouth.

[0050] Differing from the precursor auxiliary structure 230 illustrated in FIG. 2a the dental auxiliary structure 240 illustrated in FIG. 2b (together with the lower jaw 120) comprises a lower surface 233 and an upper surface 235 which are only defined based on (but not identical to) the lower border of a lower volume occupied by lower teeth in a bite state and the upper border of an upper volume occupied by upper teeth in the bite state. However, the lower surface 233 and upper surface 235 comprise distinct differences compared to the lower border and the upper border.

[0051] For example, the auxiliary structure 240 having the body 241 comprises an annular edge 247 that limits a through-hole 249 through the body 241 of the auxiliary structure 240. In particular, the auxiliary structure 240 comprises a number of edges common to the lower surface 233 and the upper surface 235, namely the annular edges 247, 251, 253, 255 and may comprise even further common edges each surrounding a through-hole 249, 252, 254, 256. Alternatively or additionally the auxiliary structure 240 comprises one or more recesses 257 which have not been present in the upper border or the lower border. The recess 257 is formed by a concave cavity which is adapted to accompany filling material (liquid or viscous) or a pre-fabricated supplement to be adhered or fixed at a corresponding tooth that requires application of a dental supplement.

[0052] While the locations of the edges and thus the surrounded through-holes 249, 252, 254, 256 are located at regions where the upper teeth contact or interfere with the lower teeth, the recess 257 is located in a region where, during a bite state or during a chewing motion, a relatively large spaced gap is present between opposing teeth. Thus, the relatively large gap may be desired to be diminished by application of a filling material or adding of a supplement to one or more of the upper teeth or the lower teeth.

[0053] The edges 247, 251, 253, 255 surrounding the tooth portion desired to be removed are visually and/or hapticly marked. Other edges 261, 263 which also limit through-holes 262, 264 are not marked with a visual or haptic indication. Thus, the dentist may recognize that tooth portions penetrating through the through-holes 262, 264 and surrounded by the edges 261, 263 are not intended to be removed during a treatment procedure. Those tooth portions may have been determined not to interfere severely with the bite state or a chewing motion.

[0054] Furthermore, also the recess 257 may be marked for the dentist to recognize that filling material is to be filled into the recess 257 or a pre-fabricated supplement is to be placed within the recess 257.

[0055] The dental auxiliary structure 240 may be placed onto the lower jaw 120 and/or onto the upper jaw 100 during a treatment procedure. Tooth portions to be removed are then recognizable by the dentist as surrounded by the visually or hapticly marked edges 247, 251, 253, 255. The annular edges 247, 251, 253 and 255 may for example surround the portions 122, 124, 126 and 128 (see FIG. 1b) of the lower teeth 123 to be partially removed.

[0056] Before inserting or putting over the teeth the auxiliary structure 240 also filling material or a pre-fabricated solid supplement may be placed within the recess 257. The patient may then be asked to close the mouth and firmly apply a bite force to the upper jaw and lower jaw such that the upper teeth 103 and the lower teeth 123 adopt a bite state, having the auxiliary structure 240 placed between the upper teeth 103 and the lower teeth 123.

[0057] The recess 257 may define a geometry and location of a supplement to be added to one of the upper teeth 103.

[0058] A recess 457 of a dental auxiliary structure 440 is in more detail illustrated in a cross-sectional side view illustrated in FIG. 4. The auxiliary structure 440 according to an embodiment of the present invention comprises a body 441 made of plastic material. The body 441 has a lower surface 433 and an upper surface 435 which may be defined based on a lower border and an upper border of a positive (i.e. 3D model of upper and lower teeth) of a dental imprint obtained in a bite state or during a chewing motion. The auxiliary structure 440, however, comprising (deviating from the lower border of a lower volume occupied by lower teeth in the bite state) a recess 457 which is in FIG. 4 filled with filling material 458. In particular, FIG. 4 illustrates a situation after which the filling material 458 has been filled into the recess 457 and after the auxiliary structure 440 has been firmly pressed onto the tooth 123 of the lower jaw including the teethridge 121.

[0059] When the auxiliary structure 440 including the filling material 458 filled into the recess 457 is pressed onto the tooth 123, excess filling material 460 or air may be expelled from the recess 457 via a filling material duct 461. A lateral extension d1 close to the recess is smaller than a lateral dimension or cross-sectional size d2 at the upper surface 435 which is the surface opposing the surface 433 where the recess 457 is arranged. The narrowest point of the filling material duct 461 is labelled with reference sign 463 and represents a predetermined breaking point of the filling material 458, 460. More than one filling material duct 461 may be provided according to different embodiments of the auxiliary structure.

[0060] FIG. 5 schematically illustrates a dental auxiliary structure 540 according to an embodiment of the present invention as put over a tooth 123 of a lower jaw including a teethridge 121. The auxiliary structure 540 comprises a body 541 limited by a lower surface 553 and an upper surface 535. The auxiliary structure 540 comprises an annular edge 547 limiting a through-hole 549 through which a portion 122 of the tooth 123 protrudes and is thus exposed. The portion 122 surrounded by the annular edge 547 is intended to be removed during a dental treatment procedure. The edge 547 may carry a visual marking for the dentist to recognize the area or location of the tooth to be partly removed.

[0061] FIG. 6 schematically illustrates a procedure how to define a lower border 665 which may serve to define a lower surface of an auxiliary structure, such as lower surfaces 433, 533 or 233 of the auxiliary structures 240, 440 and 540 illustrated in FIGS. 2b, 3, 4 and 5. For defining the lower border 665 limiting a lower volume 666 occupied by the lower teeth 123 during a chewing motion, position data are acquired during the chewing motion comprising plural bite states or motion states. As an example, in FIG. 6 three motion states of the tooth 123 are depicted, wherein the side border of the tooth 123 adopts the three states 668, 670 and 672. The lower border 665 limits the lower volume 666 which is obtained by including all volume portions which are occupied during the chewing motion by the tooth 123.

[0062] In other embodiments the lower border 665 is defined considering a single bite state, such that the lower border may be obtained by creating a positive of a conventional dental imprint.

[0063] Based on the lower border 665, a geometry or a dental auxiliary structure, such as the auxiliary structure 240, 440 or 540 may be defined. Thereby, also at least one recess and an annular edge may be provided, as described in detail with reference to FIGS. 2b, 3, 4 and 5.

[0064] FIG. 7 schematically illustrates a procedure to modify a lower border in order to arrive at a modified lower border 773 based on which a geometry of a dental auxiliary structure may be defined. In the situation illustrated in FIG. 7 it is intended to reposition the lower jaw rotation axis 125 to the lower axis 130 (see FIG. 1b). Alternatively, it may be desired to elevate the original rotation axis 125 to the elevated rotation axis 128.

[0065] The original lower border 765, such as obtained using an imprint or using the procedure as explained with reference to FIG. 6, may be modified or shifted by a particular amount s upwards, in order to define the modified lower border 773. One or more recesses, such as recess 257 as illustrated in FIG. 3 or recess 457 as illustrated in FIG. 4 may be provided for the auxiliary structure whose geometry may be defined based on the modified lower border 773.

[0066] Thus, according to embodiments of the present invention the dental auxiliary structures 240, 440 and 540 may facilitate a transfer of digital information into the real world for facilitating dental treatment by the dentist.