Laser treatment

• US 5,611,793 A
• Filed: 10/25/1994
• Issued: 03/18/1997
• Est. Priority Date: 04/30/1992
• Status: Expired due to Term

• Current Assignee: UCL Business PLC (University of London)
• Original Assignee: Institute of Dental Surgery
• Inventors: Wilson, Michael, Harvey, Wilson
• Primary Examiner(s): Sykes, Angela D.
• Assistant Examiner(s): HARRIS, SONYA C
• Application Number:
  US08/325,322
• Time in Patent Office: 875 Days
• Field of Search: 606/3, 606/10, 606/15, 606/16, 607/88, 607/89, 433/215, 433/226, 433/216, 433/229, 128/898
• US Class Current: 606/2
• CPC Class Codes: A61K 2800/434 Luminescent, Fluorescent; Optical brighteners; Photosensitizers
• CPC Class Codes: A61K 2800/81 Preparation or application process involves irradiation
• CPC Class Codes: A61K 8/042 Gels
• CPC Class Codes: A61N 2005/0606 Mouth
• CPC Class Codes: A61N 2005/0662 Visible light
• CPC Class Codes: A61N 5/0601 Apparatus for use inside the body
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent
• CPC Class Codes: A61N 5/0624 for eliminating microbes, germs, bacteria on or in the body
• CPC Class Codes: A61N 5/067 using laser light
• CPC Class Codes: A61P 1/02 Stomatological preparations, e.g. drugs for caries, aphtae, periodontitis
• CPC Class Codes: A61P 31/02 Local antiseptics
• CPC Class Codes: A61P 31/04 Antibacterial agents
• CPC Class Codes: A61P 31/10 Antimycotics
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
• CPC Class Codes: A61Q 11/00 Preparations for care of the teeth, of the oral cavity or of dentures; Dentifrices, e.g. toothpastes; Mouth rinses
• CPC Class Codes: A61Q 17/005 Antimicrobial preparations

Abstract

A method of disinfecting or sterilizing tissues of the oral cavity or a wound or lesion in the oral cavity is provided. The method comprises applying a photosensitizing compound to said tissues, wound or lesion and irradiating said tissues, wound or lesion with laser light at a wavelength absorbed by said photosensitizing compound.

Claims

1. A method of disinfecting or sterilising a locus wherein said locus is selected from the group consisting of tissues of the oral cavity and wounds and lesions in the oral cavity, said method comprising topically applying a photosensitising compound to said locus and irradiating said locus with laser light at a wave length absorbed by said photosensitising compound, so as to destroy microbes at said locus.

2. A method according to claim 1 wherein the method is selected from the group consisting of:

(a) destroying disease-related microbes in a periodontal pocket in order to treat chronic periodontitis;

(b) destroying disease-related microbes in the region between the tooth and gingiva in order to treat inflammatory periodontal diseases;

(c) destroying disease-related microbes in the region between the tooth and gingiva in order to prevent inflammatory periodontal diseases;

(d) disinfecting drilled-out carious lesions prior to filling;

(e) sterilising drilled-out carious lesions prior to filling;

(f) destroying cariogenic microbes on a tooth surface in order to treat dental caries;

(g) destroying cariogenic microbes on a tooth surface in order to prevent dental carries;

(h) disinfecting dental tissues in dental surgical procedures;

(i) disinfecting gingival tissues in dental surgical procedures;

(j) sterilising dental tissues in dental surgical procedures;

(k) sterilising gingival tissues in dental surgical procedures;

(l) treating oral candidiasis in AIDS patients;

(m) treating oral candidiasis in immunocompromised patients; and

(n) treating oral candidiasis in patients with denture stomatitis.

3. A method according to claim 2 wherein said photosensitiser is selected from the group consisting of arianor steel blue, toluidine blue O, crystal violet, methylene blue, azure blue cert, azure B chloride, azure 2, azure A chloride, azure B tetrafluoroborate, thionin, azure A eosinate, azure B eosinate, azure mix sicc., azure II eosinate, haematoporphyrin HCl, haematoporphyrin ester, aluminium disulphonated phthalocyanine and chlorins.

4. A method according to claim 3 wherein said laser light is from a laser selected from the group consisting of helium neon gas lasers and gallium arsenide lasers.

5. A method according to claim 4 wherein said laser has a power of from 1 to 100 mW and a beam diameter of from 1 to 10 mm.

6. A method according to claim 4 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.

7. A method according to claim 5 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.

8. A method according to claim 3 wherein said photosensitiser is present at said locus at a concentration of 0.00001 to 1% w/v.

9. A method according to claim 3 wherein said photosensitiser is used in the form of a pharmaceutical composition comprising said photosensitiser in solution in a pharmaceutically acceptable aqueous carrier.

10. A method according to claim 9 wherein said pharmaceutical composition further comprises a least one accessory ingredient selected from the group consisting of buffers, salts for adjusting the tonicity of said solution, antioxidants, preservatives, gelling agents and remineralisation agents.

11. A method according to claim 10 wherein said laser light is from a laser selected from the group consisting of helium neon gas lasers and gallium arsenide lasers.

12. A method according to claim 11 wherein said laser has a power of from 1 to 100 mW and a beam diameter of from 1 to 10 mm.

13. A method according to claim 11 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.

14. A method according to claim 12 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.

15. A method according to claim 2 wherein said laser light is from a laser selected from the group consisting of helium neon gas lasers and gallium arsenide lasers.

16. A method according to claim 15 wherein said laser has a power of from 1 to 100 mW and a beam diameter of from 1 to 10 mm.

17. A method according to claim 15 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.

18. A method according to claim 16 wherein said laser irradiation is conducted for a duration of from one second to five minutes and a light dose of from 5 to 30 J·

cm^-2 is administered.