CENTAURI

K933841 · Premier Laser Systems, Inc. · GEX · May 5, 1997 · General, Plastic Surgery

Device Facts

• Record ID: K933841
• Device Name: CENTAURI
• Applicant: Premier Laser Systems, Inc.
• Product Code: GEX · General, Plastic Surgery
• Decision Date: May 5, 1997
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 878.4810
• Device Class: Class 2
• Attributes: Therapeutic

Intended Use

The laser is indicated for Incision, Excision, Hemostasis, Ablation of Tissue, and Vaporization of Tissue in the oral cavity. The additional representative indications include Removal of Caries, Cavity Preparation, Modification or Etching of Eramel prior to acid etching, and Modification or Etching of Dentin prior to acid etching.

Device Story

Centauri Er:YAG Laser System uses erbium-doped yttrium aluminum garnet laser energy to ablate, excise, and vaporize oral hard and soft tissues. Operated by clinicians in dental settings, the device delivers pulsed laser energy to target sites, including enamel, dentin, and soft tissue. Water cooling is utilized to manage thermal effects and prevent pulpal damage. The system replaces or supplements traditional dental drills and acid etching procedures. By vaporizing organic material and modifying inorganic tooth structure, the laser prepares cavities and etches surfaces for restorative procedures. Clinical benefits include effective caries removal, precise cavity preparation, and surface modification without thermal damage or cracking, as verified by histological and SEM analysis. The device provides an alternative to mechanical drills, with safety profiles comparable to standard dental treatments.

Clinical Evidence

Clinical evidence includes a multi-site study of 125 randomized adult human teeth and histological/SEM analysis. Primary endpoints included caries removal efficacy, cavity preparation quality, and pulpal vitality. Results showed 100% complete caries removal and 100% adequate cavity preparation/restoration at 3 months. Histological (H&E) and SEM studies demonstrated no deleterious effects on pulpal healing or surface morphology compared to control (drill) treatments. Pulp vitality measurements showed no significant difference between laser and drill treatments pre- and post-surgery over 1.5 years.

Technological Characteristics

Er:YAG laser system; wavelength-based ablation; water-cooled delivery system to mitigate thermal damage. Operates at pulse energies ranging from 20 mJ to 430 mJ. Designed for dental hard and soft tissue applications. Connectivity and software details not specified.

Indications for Use

Indicated for incision, excision, hemostasis, ablation, and vaporization of oral cavity tissue; removal of caries; cavity preparation; and modification/etching of enamel and dentin. Contraindicated for children under 18 years of age.

Regulatory Classification

Identification

(1) A carbon dioxide laser for use in general surgery and in dermatology is a laser device intended to cut, destroy, or remove tissue by light energy emitted by carbon dioxide.(2) An argon laser for use in dermatology is a laser device intended to destroy or coagulate tissue by light energy emitted by argon.

Reference Devices

• Zach and Cohen (1965) study on pulpal heat response
• Powell et al. study on CO2 laser safety
• Hibst and Keller (1989, 1990, 1992) studies on Er:YAG ablation and thermal effects
• Paghdiwala (1988, 1993) studies on Er:YAG hard tissue application
• Walsh et al. (1989) study on Er:YAG ablation
• Arcoria (1994) study on hard tissue effects
• Kumazaki (1992) study on Er:YAG etching

Submission Summary (Full Text)

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DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Food and Drug Administration
9200 Corporate Boulevard
Rockville MD 20850

Colette Cozean, Ph.D. MAY 5 1997
President, CEO
Premier Laser Systems, Inc.
3 Morgan
Irvine, California 92618

Re: K932683 and K933841
Trade Name: Centauri Er:YAG Laser System
Regulatory Class: II
Product Code: GEX
Dated: April 28, 1997
Received: April 30, 1997

Dear Dr. Cozean:

We have reviewed your Section 510(k) notifications of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 20) and that, through periodic

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Page 2 - Colette Cozean, Ph.D.

GMP inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the *Federal Register*. Please note: this response to your premarket notification submissions does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notifications. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for *in vitro* diagnostic devices), please contact the Office of Compliance at [phone]. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at [phone]. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number [phone] or [phone] or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".

Sincerely yours,


Celia M. Witten, Ph.D., M.D.
Director
Division of General and
Restorative Devices
Office of Device Evaluation
Center for Devices and
Radiological Health

Enclosure

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Page 1 of 1

51C(k) Number (if known) K932683 & K933841

Device Name: Centauri Er:YAG Laser System

Indications For Use:

The laser is indicated for Incision, Excision, Hemostasis, Ablation of Tissue, and Vaporization of Tissue in the oral cavity. The additional representative indications include Removal of Caries, Cavity Preparation, Modification or Etching of Eramel prior to acid etching, and Modification or Etching of Dentin prior to acid etching.

The contraindications are for children under the age of 18 years.

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)


Presentation Use ☑
(Per 31 CFR 801.109)

OR

Over-The-Counter Use ☐

(Optional Format 1-2-96)

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k933841 MAY - 7 1997

# SUMMARY OF SAFETY AND EFFICACY

## A. Temperature

In a benchmark publication on temperatures which cause pulpal damage, Zach and Cohen showed that 15 % of teeth in dogs where pulpal temperature was raised to 10°F (5.5°C) had irreversible damage. These findings have been substantiated by Powell, et. Al. Therefore, if the pulpal temperature rises on only 5.5°C, one may conclude that there is no permanent damage to the pulp of the tooth due to the laser treatment.

TABLE 1 - Pulp Temperatures

| Energy Output | Repetition Rate | Time with H2O Cooling | Temperature in °C |
| --- | --- | --- | --- |
| 20 mJ | 10 Hz | 2 sec | .08° |
| 50 mJ | 10 Hz | 2 sec | 1.07° |
| 100 mJ | 10 Hz | 2 sec | .84° |
| 150 mJ | 10 Hz | 2 sec | 1.12° |
| 200 mJ | 10 Hz | 2 sec | 2.3° |
| Drill in Air | not applicable | 10 sec | .25° |
| Drill in H2O | not applicable | 10 sec | .05° |

## B. Pulp Vitality (all blinded):

1. H&E histological evidence over pulpal healing time demonstrates no deleterious effect for laser or control treatment.

2. Pulp vitality measurements over 1½ year follow-up demonstrate no compromise in pulp vitality.

3. Pulp vitality measurements on two teeth in each of 33 patients treated by laser and drill from the same patient show no difference in pulpal vitality pre-surgery, post-surgery and over three months.

4. Pulp vitality measurements on 125 randomly treated adult teeth treated by laser and drill show no significant difference between the laser and the control in pulp vitality measurements pre-surgery and after a three month period.

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## C. Surface Morphology (all blinded):

1. Animal and human studies using SEM demonstrated no changes in surface morphology except at the treatment site.

2. Animal and human studies using SEM illustrated that the drill and laser show equivalent surface changes at the treatment site.

## D. Structural Morphology

1. The ideal etched tooth presents a roughened dentin or enamel surface and no evidence of cracking, fissuring or charring. The dentin demonstrates open dentinal tubules. Organic material has been vaporized leaving the inorganic components of the tooth - leaving greater tooth surface area. In addition, a cavity preparation should show no remaining evidence of caries and a crater created by removal of tooth structure below the margin of the preparation.

2. Hibst and Keller reported on the effective removal of tooth structure with ultrastructural changes in enamel and dentin. There were no fissures or cracks. The surface was scaled and roughened without signs of thermal damage. Laser dosimetries ranged from 50 - 350 mJ.

3. Paghdiwala showed at 430 mJ, hydroxyapatite has vaporized, developing pores and surrounded by elevated fused inorganic tissue. No visible cracks radiated from the craters.

## E. Adjacent Structures

1. Adjacent structures to the treated tooth surface include soft tissue, proximal teeth and underlying bone. The damage due to inadvertent lasing of adjacent structures is usually less than the drill, since the laser does not cut effectively when defocused.

## F. Efficacy

1. Investigators rate caries removal more effective than the drill.

2. Investigators rate cavity preparation with the laser equal to the drill.

3. Investigators rate laser etching much more effective than acid etching.

4. Animal and human studies demonstrate that the Er:YAG laser is equivalent to standard treatment.

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5. In a multi-site study of 125 randomized human adult teeth, all classes of caries (I-V) were completely removed in 100% of the teeth treated.

6. In a multi-site study of 125 randomized human adult teeth all cavity preparation and restoration was still adequate after 3 months in 100% of treated teeth.

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# BIBLIOGRAPHY

1. Walsh, J.T.; Flotte, T.J.; Deutch, T.F. 1989. Er:YAG laser ablation of tissue: Effect of pulse duration and tissue type on thermal damage. Lasers in Surg and Med. 9:314-326.

2. Hibst, R., and Keller, U. 1989. Experimental studies of the application of the Er:YAG laser on dental hard substances: I. Measurement of the ablation rate. II. Light microscopic and SEM investigations. Lasers in Surg and Med. 9:38.

3. Hibst, R., and Keller, U. 1990. Heat effect of pulsed Er:YAG laser radiation. SPIE Vol 1200 II. 379-386.

4. Hibst, R., and Keller, U. 1992. Erbium:YAG laser in caries therapy: Indication and first clinical results. ICOLD.

5. Zach, Leo, and Cohen, Gerson. 1965. Pulp response to externally applied heat. O.S., O.M., and O.D. 19(4):515-530.

6. Powell, G.L.; Whisenant, B.K.; Morton, T.H. 1990. Carbon dioxide laser oral safety parameters for teeth. Lasers in Surgery and Medicine 13:548-552.

7. Arcoria, Charles J. 1994. Hard tissue effects using multiple wavelength lasers. ICOLD.

8. Paghdiwala, Abid F. 1988. Application of the Erbium:YAG laser in hard dental tissues: Measurement of the temperatures and depths of cut. ICALEO. 64:192-201.

9. Paghdiwala, Abid F. 1993. Root resection of endodontically treated teeth by Erbium:YAG laser radiation. J of Endodontics. 19(2):91-94.

11. Kumazaki, M. 1992. Results of etching with the Er:YAG laser. ISLD. 141-142.