• Thoroughly prepare the master stone die (blocking out undercut areas, applying die spacer)
• Duplicate with HF duplicating silicone (1:1)
• Remove the die after the silicone has air cured (30 min.)
• Mix HF Polyurethane for dies in a ratio of 1:1 by weight, pour into the mould and cure in a dry pressure vessel for 30 min. at 2 bar pressure.
• Then remove the resin die and drill a hole below the preparation margin for attaching a copper electrode.
• After inserting the electrode, apply silver conductive lacquer to the preparation surface up to the preparation margin and connect an electric conductor to the copper electrode.
• Allow the prepared dies to dry for 30 min. Electroforming starts automatically after programming, loading and closing the unit. After electroforming is complete, the units can be removed and taken off the resin dies.
• Remove the silver conductive lacquer remaining in the frameworks with nitric acid or by sandblasting with 50 µm aluminium oxide grit at max. 2 bar pressure.
• Remove excess electroforming at the edges up to the preparation margin with abrasive silicone rubber polishers.
• Sandblast the surfaces of the frameworks (50-110 µm, 2 bar), steam clean and apply HF Gold Paste "Spezial" as a bonder.
• Then fire the bonder at 960°C without vacuum.
• Now complete the usual porcelain firing cycles until the crown is finished.
• Select an appropriate surface conditioner when facing with composite.

The primary crown is not duplicated when fabricating Helioform secondary crowns. The copper electrode is connected to the fitting surface of the primary crown using HF Polyurethane for dies and the primary crown coated with silver conductive lacquer to the required areas for the secondary crown. The areas that are not to be electroformed can be coated with HF masking lacquer LC.

The straightforward procedure used with HELIOFORM^® results in maximum precision, which is consistently reproducible and is one of the most important features of the system.

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