Light curing device and method for curing light-polymerizable dental material

• US 6,482,004 B1
• Filed: 03/24/2000
• Issued: 11/19/2002
• Est. Priority Date: 03/26/1999
• Status: Expired due to Term

• Current Assignee: Ivoclar AG
• Original Assignee: Ivoclar AG
• Inventors: Burtscher, Peter, Rohner, Gottfried, Senn, Bruno
• Primary Examiner(s): Lewis, Ralph A.
• Application Number:
  US09/534,954
• Time in Patent Office: 970 Days
• Field of Search: 433/29, 433/226, 433/229, 522/908, 315/291, 362/804
• US Class Current: 433/29
• CPC Class Codes: A61C 19/004 Hand-held apparatus, e.g. guns
• CPC Class Codes: Y10S 362/804 Surgical or dental spotlight
• CPC Class Codes: Y10S 522/908 Dental utility

Abstract

A light curing device has a light source for curing light-polymerizable dental materials. A control circuit controls the light output of the light source according to a pre-determined output profile. The output profile has a starting time period with a decreased output relative to a maximum output, followed by a main curing time period. In the main curing time period, a pulsed output with alternating high output value and low output value is provided.

Claims

1. A light curing device for directly curing light-polymerizable dental material with decreased curing shrink-age;

said device comprising;

a light source for directly curing light-polymerizable dental materials, the light source capable of having light output values which vary between nil and a high light output value; and

means to progressively control the output value of the light source during direct curing of the light-polymerizable dental material by initially increasing the light output value from nil to a low light output value of about 50% of the high light output value during a starting time period, and by subsequently varying the light output value between the low output value and the high light output value during a main curing time.

2. A light curing device according to claim 1, wherein said light source has a spiral filament and alternatingly emits light of greater and lesser intensity.

3. A light curing device according to claim 1, wherein said light output increases during said starting time period with an initial steep incline, followed by a flatter incline.

4. A light curing device according to claim 1, wherein the means to control the output of the light source is a control circuit, said control circuit constantly controlling said light output according to said output profile.

5. A light curing device according to claim 4, wherein said control circuit comprises a PID-controller, said PID controller taking into account a dead time of said light source.

6. A light curing device according to claim 4, further comprising a supply source and a hand-held instrument wherein said light source is mounted in said hand-held instrument, and wherein said control circuit is mounted in the supply source and has a control path extending between said hand-held instrument and said supply source.

7. A light curing device according to claim 6, wherein said control path is an electric cable.

8. A light curing device according to claim 1, wherein curve flanks of said output profile for an output increase from said low output value to said high output value have a slant corresponding to more than 10% of a pulsation period of said output profile during said main curing time period.

9. A light curing device according to claim 1, wherein said light source is a halogen lamp that continues to emit light during period durations of light emissions at said low/output value.

10. A light curing device according to claim 1, wherein said light source is a laser diode.

11. A light curing device according to claim 1, wherein said light source is an arrangement of LEDs.

12. A light curing device for directly curing a light-polymerizable dental material with decreased curing shrinkage comprising:

a light source for directly curing light-polymerizable dental materials, the light source capable of having light output values which vary between nil and a high light output value; and

means to progressively control the output value of said light source according to a pre-determined output profile, wherein said output profile has a starting time period of not less than 10 seconds with an initial output value of nil and a final low output value of about 50% of the high light output value, followed by a main curing time period of at least 20 seconds; and

wherein in said main curing time period a pulsed output value with alternating high light output value and low light output value is provided.

13. A light curing device according to claim 12, wherein a sequence of said high light output value and said low output value is periodic during said main curing time with periodic durations ranging between 3 and 5 seconds.

14. A process for curing by light a light-polymerizable dental material with decreased curing shrinkage;

the process including;

providing a light source for curing the light-polymerizable dental material, the light source capable of having light output values which vary between nil and a high light output value;

controlling the output value of the light source progressively to initially increase the light output value from nil to a low light output value of between 25% and 60% of said high light output value during a starting time period, and

to subsequently vary the light output value between the low output value and the high light output value during a main curing time.