Dental furnace

• US 10,260,811 B2
• Filed: 01/13/2016
• Issued: 04/16/2019
• Est. Priority Date: 03/05/2008
• Status: Active Grant

• Current Assignee: Ivoclar Vivadent AG
• Original Assignee: Ivoclar Vivadent AG
• Inventors: Rohner, Gottfried, Pokorny, Walter, Grunenfelder, Robert, Rothbrust, Frank
• Primary Examiner(s): Chou, Jimmy
• Application Number:
  US14/994,405
• Publication Number:
  US 20160195334A1
• Time in Patent Office: 1,189 Days
• Field of Search: 431 1, 431 32, 431 49, 431930, 433 32, 433 61, 433 62, 219425
• CPC Class Codes: A61C 13/0006 Production methods
• CPC Class Codes: A61C 13/12 Tools for fastening artificial teeth; Holders, clamps, or stands for artificial teeth A61C8/0089 takes precedence
• CPC Class Codes: A61C 13/20 Methods or devices for soldering, casting, moulding or melting A61C13/04, A61C13/081 take precedence
• CPC Class Codes: A61C 5/77 Methods or devices for making crowns
• CPC Class Codes: F27B 17/025 for dental workpieces

Abstract

The invention relates to a dental furnace wherein a firing chamber is heated up in a first heating-up period at a first heating-up rate of more than 501 K/min, in particular more than 1001 K/min, which heats the furnace to at least 10001 C., in particular to 1100-12501 C. The first heating-up period is followed by an intermediate heating period, which is at least five minutes long, in particular at least ten minutes long, the gradient or heating-up rate of which is adapted to the material to be sintered in the dental furnace (10), and wherein this is followed by an end heating-up period (44) during which heating up is effected at a heating-up rate of more than 301 K/min, in particular approximately 501 K/min, and wherein during this the furnace temperature is held for at least five minutes, in particular for at least 25 minutes, above the temperature toward the end of the first heating-up period, and wherein forced cooling of the furnace (10) is performed after this.

Claims

1. A system comprising

a dental machining device for manufacturing at least one dental object and

a dental furnace for sintering the at least one dental object;

wherein the dental machining device and the dental furnace are connected to each other via a digital data connection comprising a wired or wireless data connection;

wherein the dental machining device provides data of the at least one dental object which is to be manufactured in said dental machining device prior to sintering the at least one dental object in the dental furnace;

wherein the data provided by the dental machining device comprise at least meta data of the at least one dental object to be manufactured by the dental machining device; and

wherein control commands are exchanged between the dental machining device and the dental furnace.

2. The system according to claim 1, wherein the dental machining device comprises a CAD/CAM (computer-aided design/computer-aided machining) device.

3. The system according to claim 1 wherein the at least meta data to be provided by the dental machining device comprise further information of a material of the at least one dental object sintered.

4. The system according to claim 1 wherein the at least meta data to be provided by the dental machining device comprise further information of a mass of the at least one dental object sintered.

5. The system according to claim 1 wherein the at least meta data to be provided by the dental machining device comprise further information of the type of the at least one dental object sintered.

6. The system according to claim 5 wherein the further information of the type of the at least one dental object comprises a veneer, a crown, or a bridge.

7. The system according to claim 1 wherein the at least meta data to be provided from the dental machining device comprise further information of how many dental objects are to be sintered together in one firing cycle of the dental furnace.

8. The system according to claim 1 wherein the at least meta data to be provided from the dental machining device comprise further information of whether single or multiple firing cycles are needed to sinter the at least one dental object.

9. The system according to claim 1 wherein a control device of the dental machining device determines a remaining machining time for manufacturing the at least one dental object based on the at least meta data of the at least one dental object be to manufactured, and initiates a pre-heating of the dental furnace based on a determined remaining machining time.

10. The system according to claim 1 wherein the dental furnace further comprises a control device and wherein the dental furnace is preset to a desired pre-heating temperature;

and

wherein the control device of the dental furnace determines a time span needed for pre-heating the dental furnace up to a preset pre-heat temperature, and

wherein the dental furnace provides said determined time span for pre-heating the dental furnace up to the preset pre-heat temperature as timing data to the dental machining device.

11. The system according to claim 1 wherein the at least meta data to be provided from the dental machining device comprise further information of whether drying of the at least one dental object is necessary or not prior to sintering.

12. The system according to claim 1 further comprising an oven hood being pivotably mounted to an oven base of the dental furnace and wherein the oven hood can be pivoted by means of an oven hood driving means, in order to adjust an angle of aperture of the oven hood, and

wherein the dental furnace is operated in a drying operation mode prior to sintering of the at least one dental object based on the at least meta data provided, and

wherein drying of the at least one dental object is obtained by applying heat from the pre-heated said dental furnace while the oven hood is in an at least partially opened state.

13. The system according to claim 12 wherein the angle of aperture of the oven hood is continuously controlled by a control device of the dental furnace, in order to adjust a temperature of the at least one dental object to be dried to a desired optimum temperature and to hold the temperature during drying of the at least one dental object based on the at least meta data provided.

14. The system according to claim 12 wherein the angle of aperture of the oven hood is set to a fixed value by a control device of the dental furnace, and wherein the temperature of the at least one dental object to be dried is controlled by accordingly controlling heat energy provided by heating, in order to obtain and to hold a desired optimum temperature during drying of the at least one dental object based on the at least meta data provided.

15. The system according to claim 12 wherein the system further comprises a temperature detection means arranged outside the heating chamber of the dental furnace wherein a detection range of the temperature detection means is directed toward the heating chamber and wherein the temperature detection means is capable of a temperature detection of the at least one dental object when the oven hood is in an at least partially opened state.

16. The system according to claim 15 wherein the temperature detection means is coupled to a control device of the dental furnace and

wherein the control device is capable of detecting a completion of the drying process of the at least one dental object based on temperature values provided from the temperature detection means, and

wherein the control device automatically starts the sintering of the at least one dental object after said detection of the completed drying process, in particular after completely closing the oven hood.

17. The system according to claim 1 wherein the dental furnace comprises

a heating chamber heated up by at least one form of heating component comprising resistant heating, IR heating, induction heating, spark plasma sintering, pulsed electric current sintering or a combination thereof, wherein the dental furnace is configured such that

the heating chamber is heated up in a first heating-up period at a first heating-up rate of more than 35°

K/min, which heats the dental furnace to at least 1000°

C.,

wherein the first heating-up period is followed by an intermediate heating period, which is at least five minutes long,

wherein the intermediate heating period is followed by an end heating-up period during which heating up is effected at a heating-up rate of more than 30°

K/min, and wherein the end heating-up period is followed by a hold period in which a temperature of the dental furnace is held for at least five minutes above a temperature reached toward an end of the first heating-up period, and wherein forced cooling of the dental furnace is performed after the hold period,

wherein gradients or heating-up rates both of said first heating-up period and an end heating-up rate are each adapted to a material to be sintered in the dental furnace, and

wherein the forced cooling of the dental furnace takes place at a cooling rate which is based on both the rates of the first heating-up period and the end heating-up rate.

18. The system according to claim 17

wherein the first heating-up rate is more than 100°

K/min, which heats the dental furnace to more than 1100°

C.,

wherein the intermediate heating period is at least five minutes long,

wherein the end heating-up period is effected at a heating-up rate of more than 50°

K/min, and wherein the end heating-up period is followed by a hold period which is at least 25 minutes long,

wherein the gradients or heating-up rates both of said first heating-up period and said end heating-up rate are each adapted to a physical mass and/or dimensions of the dental object to be sintered in the dental furnace.

19. The system according to claim 17

wherein the intermediate heating period is at least ten minutes long.