Solid Free-Form Fabrication Methods For The Production of Dental Restorations

• US 20080318189A1
• Filed: 07/31/2008
• Published: 12/25/2008
• Est. Priority Date: 07/10/1998
• Status: Active Grant

• Current Assignee: Ivoclar Vivadent AG
• Original Assignee: Ivoclar Vivadent AG
• Inventors: Brodkin, Dmitri, Panzera, Carlino, Borenstein, Stefan, Day, Grant P., Prasad, Arun
• Granted Patent: US 9,155,597 B2
• Time in Patent Office: Days
• US Class Current: 433/223
• CPC Class Codes: A61C 13/0003 Making bridge-work, inlays, implants or the like
• CPC Class Codes: A61C 13/0004 Computer-assisted sizing or machining of dental prostheses
• CPC Class Codes: A61C 13/0019 using three dimensional printing
• CPC Class Codes: A61C 5/35 Pins; Mounting tools or dispensers therefor
• CPC Class Codes: A61C 5/77 Methods or devices for making crowns
• CPC Class Codes: A61K 6/802 comprising ceramics
• CPC Class Codes: A61K 6/807 comprising magnesium oxide
• CPC Class Codes: A61K 6/816 comprising titanium oxide
• CPC Class Codes: A61K 6/818 comprising zirconium oxide
• CPC Class Codes: A61K 6/822 comprising rare earth metal oxides
• CPC Class Codes: A61K 6/838 Phosphorus compounds, e.g. apatite
• CPC Class Codes: A61K 6/84 comprising metals or alloys
• CPC Class Codes: A61K 6/849 comprising inorganic cements
• CPC Class Codes: A61K 6/884 comprising natural or synthetic resins
• CPC Class Codes: A61K 6/887 Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61K 6/891 Compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61K 6/893 Polyurethanes
• CPC Class Codes: B29C 64/153 using layers of powder being selectively joined, e.g. by selective laser sintering or melting
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing
• CPC Class Codes: C08L 33/08 : Homopolymers or copolymers of acrylic acid esters
• CPC Class Codes: C08L 63/00 : Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• CPC Class Codes: C08L 83/04 : Polysiloxanes

Abstract

Solid free form fabrication techniques can be utilized indirectly to manufacture substrates, dies, models, near-net shapes, shells, and wax-ups that are then used in the manufacture of dental articles. Digital light processing is the most preferred indirect method for the production of substrates. After the substrates are produced, various coating or deposition techniques such as gel casting, slip casting, slurry casting, pressure infiltration, dipping, colloidal spray deposition or electrophoretic deposition are used to manufacture the dental article.

Claims

1. A process for manufacturing dental restorations comprising:

(a) depositing a layer of a slurry of a ceramic material;

(b) curing the layer of the ceramic material;

(c) repeating steps (a) and (b) a number of times to produce a number of layers of ceramic material which are bonded to one another to form a shape of a dental restoration;

(d) hardening the shaped material to form the dental restoration.

2. The method of claim 1 wherein hardening comprises sintering or curing the shaped material.

3. The process of claim 1 wherein the slurry comprises a ceramic material and a binder.

4. The process of claim 3 further comprising burning out the binder prior to hardening step (d).

5. The process of claim 3 wherein the binder is removed during the hardening step (d).

6. The process of claim 1 wherein the hardening step comprises sintering the shaped material to full density.

7. The process of claim 1 wherein the ceramic material comprises alumina, zirconia, mullite, silica, spinel, tricalcium phosphate, apatite, fluoroapatite, hydroxyapatite, or mixtures thereof.

8. The process of claim 1 wherein the layers of ceramic material form a selected pattern.

9. The process of claim 8 wherein the selected pattern is based on a computer assisted design.

10. The process of claim 1 wherein pigments, opacifiers, and/or fluorescing agents are added to the ceramic material prior to deposition thereof.

11. The process of claim 1 wherein pigments, opacifiers, and/or fluorescing agents are added to the ceramic material after deposition thereof.

12. The process of claim 1 wherein pigments, opacifiers, and/or fluorescing agents are added to the ceramic material during deposition thereof.

13. The process of claim 3 wherein the binder comprises an inorganic or an organic material.

14. The process of claim 3 wherein the binder comprises a molten thermoplastic material or a wax-containing material.

15. The process of claim 3 wherein the binder comprises polycarbosilazane or tetraethylorthosilicate.

16. The process of claim 1 wherein the dental restoration comprises denture teeth, bridges, crowns, space maintainers, tooth replacement appliances, orthodontic parts, orthodontic retainers, dentures, posts, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, splints, partial crowns, teeth, cylinders, pins, and connectors.

17. A process for producing a dental restoration comprising:

providing a mixture of ceramic powder material dispersed in a binder; and

dispensing the mixture from a dispensing apparatus onto a platform to build a free-standing three dimensional dental restoration layer by layer.

18. The process of claim 17 comprising curing a layer before dispensing the next layer.

19. The process of claim 17 further comprising hardening the free-standing three dimensional dental restoration.

20. The method of claim 19 wherein hardening comprises curing or sintering the free-standing three dimensional dental restoration.

21. The process of claim 17 further comprising burning out the binder prior to hardening the free-standing three dimensional dental restoration.

22. The process of claim 19 wherein the binder is removed during hardening the free-standing three dimensional dental restoration.

23. The process of claim 19 wherein the hardening step comprises sintering the free-standing three dimensional dental restoration to full density.

24. The process of claim 17 wherein the dispensing apparatus comprises a continuous stream print head or drop-on-demand stream print head.

25. The process of claim 17 wherein the mixture is dispensed in the form of a bead, stream, or droplet.

26. The process of claim 25 wherein the bead, stream or droplet comprises a slurry or a liquidfied filament.

27. The process of claim 26 wherein the slurry comprises a ceramic powder and a binder.

28. The process of claim 26 wherein the liquified filament comprises ceramic powder and a binder.

29. The process of claim 17 wherein the binder comprises an inorganic or an organic material.

30. The process of claim 17 wherein the binder comprises a molten thermoplastic material or a wax-containing material.

31. The process of claim 17 wherein the binder comprises polycarbosilazane or tetraethylorthosilicate.

32. The process of claim 17 wherein pigments, opacifiers, and/or fluorescing agents are added to the ceramic powder material during, after or before dispensing thereof.

33. The process of claim 17 wherein the dental restoration comprises denture teeth, bridges, crowns, space maintainers, tooth replacement appliances, orthodontic parts, orthodontic retainers, dentures, posts, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, splints, partial crowns, teeth, cylinders, pins, and connectors.