← Product Code [EJT](/submissions/DE/subpart-d%E2%80%94prosthetic-devices/EJT) · K990670

# HELIOFORM GOLD-BASED ALLOY (K990670)

_C. Hafner GmbH & Co. · EJT · Apr 2, 1999 · Dental · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/DE/subpart-d%E2%80%94prosthetic-devices/EJT/K990670

## Device Facts

- **Applicant:** C. Hafner GmbH & Co.
- **Product Code:** [EJT](/submissions/DE/subpart-d%E2%80%94prosthetic-devices/EJT.md)
- **Decision Date:** Apr 2, 1999
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 872.3060
- **Device Class:** Class 2
- **Review Panel:** Dental
- **Attributes:** Therapeutic

## Indications for Use

Indicated for fixed and removable dental tooth replacement as follows: Crowns Inlays, Onlays, Overlays, Partial Crowns Telescopes, Cones, Overdentures Direct Technique Double Crown Systems Implant Suprastructures Bridge Structures Baseplates

## Device Story

Helioform system fabricates dental restorations (crowns, bridges, inlays, etc.) via electroforming process. System uses electroconductive polyurethane duplicate die as cathode in electroplating tank containing fine gold electrolyte (HF-Elektrolyt). Electric current triggers deposition of gold ions onto cathode; gold thickness controlled by duration of live cycle (approx. 20 um/hour). Resulting framework (99.99% fine gold) provides biocompatible, high-precision base for ceramic facings. Used in dental laboratories by technicians. Output is gold framework fitted with porcelain; enables conservative tooth preparation, protects dental pulp, and offers superior marginal fit/fracture resistance compared to base metals or all-ceramic restorations.

## Clinical Evidence

No clinical trials; evidence based on in-vitro studies and established dental technology. In-vitro studies evaluated marginal fit, marginal leakage, adhesion, stability, and fracture resistance. Results indicate Helioform marginal fit is superior to full ceramic or titanium crowns; fracture resistance exceeds that of base metals, including titanium. Clinical advantages cited include conservative preparation and pulp protection.

## Technological Characteristics

Gold-based alloy (99.99% fine gold). Electroforming principle using polyurethane dies coated with conductive silver spacer. Electrolyte: non-cyanide gold sulfite solution. Density: 19.3 g/cm³; Melting point: 1064 °C; Vickers Hardness: 100 HV (as-formed), 25 HV (post-firing). Coefficient of thermal expansion: 15.2 µm/m·K. Compatible with porcelains having CTE 13.8–17.2 µm/m·K.

## Regulatory Identification

A noble metal alloy is a device composed primarily of noble metals, such as gold, palladium, platinum, or silver, that is intended for use in the fabrication of cast or porcelain-fused-to-metal crown and bridge restorations.

## Special Controls

*Classification.* Class II (special controls). The special control for these devices is FDA's “Class II Special Controls Guidance Document: Dental Noble Metal Alloys.” The devices are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 872.9. See § 872.1(e) for availability of guidance information.

## Predicate Devices

- Progold Electrocoping System ([K980613](/device/K980613.md))

## Submission Summary (Full Text)

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\$\mathcal{K}\$ 990670

Image /page/0/Picture/2 description: The image shows the logo for C. Hafner. The logo consists of the text "C. HAFNER" in a bold, sans-serif font, with a stylized symbol to the right. Below the name is the text "GOLD- UND SILBERSCHEIDEANSTALT" in a smaller, sans-serif font, set against a black background.

## 510 (k) Summary

- (a) (1) C. HAFNER GmbH & Co Bleichstraße 13-17 D-75173 Pforzheim

| Telephone: | 07231/920-210 |
|------------|---------------|
| Fax:       | 07231/920-207 |

Contact person Dr. Helmut Knosp

1999-01-29 Date:

- Name of device: Helioform (a) (2) consisting of HF-Goldkonzentrat HF-Elektrolyt Electrolytic gold
Classification name: gold based alloy

- Legally marketed equivalent device: (a) (3) Progold Electrocoping System 510 (k) number: K 980613
- The Helioform System is used to fabricate i. e. inlays, onlays and (a) (4) crowns by a electroforming process. Electroformed gold framework that can be fitted with ceramic facings are an ideal combination of function, esthetic appeal and biocompatibility. The galvano-forming procedure of the Helioform System is as follows:

An electroconductive polyurethane duplicate die is used as a cathode in an electroplating tank. The electrolyte in this tank contains fine gold in solution (HF-Elektrolyt).

When the electric current between the anode and cathode is activated, positively charged gold ions will travel from the electrolyte to the cathode, where they are deposited and form a gold plating.

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Image /page/1/Picture/0 description: The image shows the logo for C. Hafner Gold- und Silberscheideanstalt. The logo consists of the company name in bold, sans-serif font, with the words "GOLD- UND SILBERSCHEIDEANSTALT" in a black rectangle below the name. To the right of the name is a stylized graphic of a crucible or other metallurgical vessel.

Galvanoformed parts are produced in Helioform technique using polyurethane dies. The dies are coated with a conductive silver spacer and serves as the cathode of the electroplating circuit.

The electrolyte consists of a non-cyanide gold sulfite solution to which non-cyanide gold concentrate (HF-Goldkonzentrat) is continuously released to replace the gold precipitated on the cathode.

When the electric current is turned on, gold will be deposited on the polyurethane die. The thickness of the laver depends on the duration of the live cycle (approximately 20 um per hour). It can be selected between 200 - 400 um.

The galvanoformed item contains only fine gold with a fineness of 99,99 %. The amount of material required is only about 60 % of what a comparable casting alloy with high gold content would require. All porcelains which are used together with ceramic alloys with coefficient of thermal expansion between 13.8 and 17.2 um/m·K can be fired on galvanoformed Helioform items. Physical properties of galvanoformed Helioform gold are:

| Density:                                    | 19,3 g/cm³                 |
|---------------------------------------------|----------------------------|
| Melting point:                              | 1064 °C                    |
| Vickers Hardness after galvanoforming:      | 100 HF                     |
| Vickers Hardness after firing on porcelain: | 25 HV                      |
| Grain size after galvanoforming:            | < 2 μm                     |
| Grain size after firing on porcelain:       | 50 μm                      |
| Coefficient of thermal expansion:           | 15,2 µm/m·K<br>(25-500 °C) |

(a) (5) Since 1988 intensive efforts were made to introduce galvanoforming to crown and bridge technology. These efforts were preceded by studies of the stability under load and the bond strength of galvano-ceramic crowns. Based on a large number of publications, it may be stated that the range of possible indications has been extended considerably from inlays, crowns, partials to bridges, baseplates, biteplates, telescopic and conical crown systems and implant suprastructures. Even the fabrication of bridges in a single-piece galvanoforming technique has been tested.

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Image /page/2/Picture/0 description: The image shows the logo for C. Hafner Gold- und Silberscheideanstalt. The logo consists of the company name in bold, sans-serif font, with the "C. HAFNER" on the top line and "GOLD- UND SILBERSCHEIDEANSTALT" on the bottom line. To the right of the name is a stylized graphic of a crucible.

- (a)(6) Helioform System and Progold Electrocoping System are based on similar technological characteristics.
Differences are as follows:

| Progold                                                                      | Helioform                                                                                                                                                                                     |
|------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Using of stone dies excellent<br>bond strength to<br>conventional porcelains | Using of polyurethane dies<br>excellent bond strength and<br>compatibility to conventional<br>porcelains as well as to low firing<br>porcelains with high coefficient of<br>thermal expansion |
| 99,96% electroformed fine<br>gold 16 gold copings in 6-7<br>hours            | 99,99% electroformed fine fold 10-<br>20 gold copings in 10 hours                                                                                                                             |
| Gold Electrolyte with 15 g/l<br>gold content                                 | Gold Electrolyte with 10 g/l gold<br>content Concentrate with 100 g<br>gold content                                                                                                           |
| recovery capabilities of<br>precious metals from solution                    | Recovery recommendations of fine<br>gold from Electrolyte                                                                                                                                     |
| Stone divesting capability                                                   | Thermal separation of<br>polyurethane dies                                                                                                                                                    |

- (b)(1) Numerous in-vitro studies were conducted that looked at fit, marginal leakage, adhesion of bonding materials, stability and fracture resistance as well as on the metal/ceramic interface. What is particularly interesting in this respect is that the marginal fit of Helioform crowns is evaluated as better than those of full ceramic or titanium crowns. Studies of the fracture resistance, too, have shown better results of Helioform crowns than for base metals - including titanium.
- (b)(2) Clinical studies have proved that crown and bridge prosthodontics with or without implants fabricated with the galvanoforming process has enormous advantages over other technologies. The thin gold jacket leaves more space for the ceramic layer which permits a more conservative preparation and thus protects the dental pulp better than an all ceramic or conventional metal ceramic restoration.

273611/C/1 8B6B01_

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Image /page/3/Picture/0 description: The image shows the logo for C. Hafner Gold- und Silberscheideanstalt. The logo consists of the company name in bold, sans-serif font, with the words "GOLD- UND SILBERSCHEIDEANSTALT" in a black rectangle below the name. To the right of the name is a stylized image of a crucible.

- (b)(3) Inlays, crowns, and bridges produced by galvanic precipitation of fine gold has become firmly established in dental technology. The advantages are obvious. In the Heliform procedure 99,99% fine gold is precipitated in the form of a hard, fine-grained structure. By contrast with casting there are no impurities of porosities. Worked procedures at the dental office and at the dental laboratory either remain practically unchanged, or they are even simplified. A high degree of biocompatibility, precision of fit, pulp protection, cementability, esthetics, and reasonable production costs are the most important advantages of galvanoformed restorations.
The Helioform System is as safe and as effective as the legally marketed Progold Electrocoping System. An advantage of Helioform precipitations is higher fineness of gold (99,99%) which yields to a better biocompatibility.

273611/C/1 8B6B01

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

APR 2 1999

C. Hafner GmbH & Company C/O Mr. John F. Lemker Bell, Boyd & Llyod Three First National Plaza 70 West Madison Street, Suite 3300 Chicago, Illinois 60602-4207

Re : K990670 Helioform Gold-Based Alloy Trade Name: Regulatory Class: II Product Code: EJT February 26, 1999 Dated: March 2, 1999 Received:

Dear Mr. Lemker

We have reviewed your Section 510(k) notification 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. ਬੈ substantially equivalent determination assumes compliance with the Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and that, through periodic GMP inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP requlation 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 submission does not affect any obligation you might have under sections 531 through 542 of

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Page 2 - Mr. Lemker

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 notification. 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 requlation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4692. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note one regulation entitled, "Misbranding by reference fo
the regulation entitled, "Misbranding by reference to information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".

Sincerely yours,

Palmeux Coccimite/for

Timothy A. Ulatowski Director Division of Dental, Infection Control, and General Hospital Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Image /page/6/Picture/0 description: The image shows the text "K990670 C. HAFNER GOLD- UND SILBERSCHEIDEANSTALT". The text is in black and is on a white background. The text is arranged in two lines, with the first line containing the number "K990670" and the second line containing the text "C. HAFNER GOLD- UND SILBERSCHEIDEANSTALT".

K990670

Helioform

510 (k) Number:

Device Name:

Indications For Use:

Indicated for fixed and removable dental tooth replacement as follows:

Crowns Inlays, Onlays, Overlays, Partial Crowns Telescopes, Cones, Overdentures Direct Technique Double Crown Systems Implant Suprastructures Bridge Structures Baseplates

Detailed descriptions of the above indications can be found in the instructions for Use under 5.1 to 5.7

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use
(per 21 CFR 801.109) 
✓

OR

Over-the-Counter Use

X

Angela Blackwell for MSR

(Division Sign-Off) Division of Dental, Infection Control, and General Hospital Devices 510(k) Number 490670

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