METHODS FOR FABRICATING DENTAL RESTORATIONS

• US 20170056138A1
• Filed: 04/30/2015
• Published: 03/02/2017
• Est. Priority Date: 05/02/2014
• Status: Active Grant

• Current Assignee: University of Louisville
• Original Assignee: University of Louisville
• Inventors: MORTON, Dean, ZANDINEJAD, Amirali, LIN, Wei-Shao
• Granted Patent: US 10,716,648 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 5/77 Methods or devices for making crowns
• CPC Class Codes: A61K 6/15 Compositions characterised by their physical properties
• CPC Class Codes: A61K 6/80 Preparations for artificial teeth, for filling teeth or for capping teeth
• CPC Class Codes: A61K 6/813 comprising iron oxide
• CPC Class Codes: B28B 1/001 Rapid manufacturing of 3D objects by additive depositing, agglomerating or laminating of material selective deposition modelling of metallic powder B22F10/00; rapid manufacturing of 3D objects in general and in particular of plastics B29C64/00
• CPC Class Codes: B29C 2035/0822 using IR radiation
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 35/08 by wave energy or particle radiation B29C64/00, B29C71/04 take precedence
• 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: B29L 2031/7536 Artificial teeth
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing

Abstract

A method of fabricating a dental restoration is provided that includes the initial step of providing a powder of a dental material. An amount of a binder is then selectively deposited onto the powder of the dental material to produce an unfinished layer of the dental material. Multiple layers of the dental material are then produced by continually providing a powder of dental material and selectively depositing an amount of a binder until a three-dimensional unfinished model is produced. The unfinished model is then separated from an amount of unaffected powder, and is sintered to produce a three-dimensional dental restoration having a functionally-graded structure.

Claims

1. A method of fabricating a dental restoration, comprising the steps of:

(a) providing a powder of a dental material;

(b) selectively depositing an amount of a binder onto the powder of the dental material to produce an unfinished layer of the dental material;

(c) repeating steps (a) and (b) to produce a three-dimensional unfinished model;

(d) sintering the unfinished model to produce a three-dimensional dental restoration having a functionally-graded structure.

2. The method of claim 1, wherein the dental material comprises a ceramic.

3. The method of claim 1, wherein providing a powder of a dental material comprises deploying a layer of powder via a powder deploy mechanism.

4. The method of claim 3, wherein the powder deploy mechanism is a rotating roller.

5. The method of claim 1, wherein providing a powder of a dental material comprises varying an amount of powder of the dental material provided to produce a layer of dental material having a portion with an elasticity, hardness, or porosity different than that of an adjacent portion.

6. The method of claim 1, further comprising a step of curing the binder prior to repeating step (a) and/or prior to sintering the unfinished model.

7. The method of claim 6, wherein the step of curing the binder comprises subjecting the binder to thermal radiation, ultraviolet radiation, or both.

8. The method of claim 6, wherein curing the binder comprises varying an amount of time the binder is cured to produce a layer of dental material having a portion with an elasticity, hardness, or porosity different than that of an adjacent portion.

9. The method of claim 1, wherein the binder includes one or more organic compositions, inorganic compositions, surfactants, dispersants, and combinations thereof.

10. The method of claim 9, wherein selectively depositing a binder onto the powder of the dental material further comprises varying the amount of inorganic compositions included in the binder to produce a layer of dental material having a portion with an elasticity, hardness, or porosity different than that of an adjacent portion.

11. The method of claim 9, wherein the inorganic compositions comprise iron oxide particles.

12. The method of claim 1, wherein selectively depositing a binder onto the powder of the dental material is performed by an inkjet printing platform.

13. The method of claim 1, wherein selectively depositing the amount of the binder onto the powder of the dental material comprises varying the amount of binder deposited onto the powder to produce a layer of dental material having a portion with an elasticity, hardness, or porosity different than that of an adjacent portion.

14. The method of claim 1, wherein the amount of the binder selectively deposited onto the powder of dental material is sufficient to produce a binder saturation level of about 45% to about 75%.

15. The method of claim 1, wherein steps (a) and (b) are repeated about 10 to about 1,000 times.

16. The method of claim 1, wherein sintering the functionally-graded structure comprises heating the unfinished model to a temperature of about 750°

C. to about 950°

C.

17. The method of claim 1, wherein sintering the functionally-graded structure comprises heating the unfinished model to a temperature of about 500°

C. for a first predetermined time period, and subsequently heating the unfinished model to a temperature of about 750°

C. to about 950°

C. for a second predetermined time period.

18. The method of claim 17, wherein the first predetermined time period is about 30 min and the second predetermined time period is about 1 min to about 9 hrs.

19. The method of claim 1, wherein the dental restoration includes an outer enamel-like portion and an inner dentin-like portion, the outer enamel-like portion having an outer layer and an inner layer.

20. The method of claim 19, wherein the outer enamel-like portion has a width extending from the outer layer to the inner layer, and wherein a hardness and an elastic modulus of the enamel-like portion reduces across the width of the enamel-like portion from the outer layer to the inner layer.

21. The method of claim 19, wherein the outer layer of the enamel-like portion has an elastic modulus of about 100 GPa to about 140 GPa and a hardness of about 0.8 GPa to about 1.2 GPa, and wherein the inner layer of the enamel like-portion has an elastic modulus of about 40 GPa to about 80 GPa and a hardness of about 0.4 GPa to about 0.8 GPa.

22. The method of claim 19, wherein the dentin-like portion has an elastic modulus of about 15 GPa to about 45 GPa.

25. A dental restoration produced by the process according to claim 1 or claim 23.

23. A method of fabricating a dental restoration, comprising the steps of:

(a) providing a powder of a dental material;

(b) selectively depositing an amount of a binder sufficient to produce a binder saturation level of about 45% to about 75% onto the powder of the dental material to thereby produce an unfinished layer of the dental material;

(c) curing the binder;

(d) repeating steps (a) to (c) to produce a three-dimensional unfinished model; and

(e) heating the unfinished model to a first temperature of about 500°

C. for a first predetermined time period and to a second temperature of about 750°

C. to about 950°

C. for a second predetermined time period to produce a three-dimensional dental restoration having a functionally-graded structure.

24. The method of claim 23, wherein the first predetermined time period is about 30 min and the second predetermined time period is about 1 min to about 9 hrs.