The Mosi2 heating elements have been identified as the best choice for the modern dental sintering furnace due to the below characteristics:
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High Resistivity.
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High Melting Point.
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Low-Temperature Coefficient of Resistance.
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Positive Temperature Coefficient of Resistance.
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High Oxidising Temperature.
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High Ductility and Flexibility.
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Sufficient Mechanical Strength
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Should Withstand Vibrations.
To increase the lifespan of mosi2 heating elements of your zirconia sintering furnace and in an attempt to limit the effects of contamination from color liquids, it's more and more important for decreasing cost and increasing benefit for your own dental laboratory, so let's understand the reason it happens.
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both acid and water-based color liquids contain alkali metals that will attack the silica surface of heating elements and oxidize the surface layer. This oxidation is most commonly noticed in MoSi2 elements because their lifespan tends to be much longer than that of SiC elements. This is due to their high surface temperature rating and the fact that most contamination is noticed in new ovens after approximately 1 year of usage.
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On MoSi2 elements, this oxidation can be seen as whitepox or white spots on the surface of the element.
To avoid contamination and to keep oxidation from occurring, it is important to know how to handle colored liquids and colored zirconia units prior to introducing units into the sintering oven. It is also imperative to maintain the sintering oven with a regular schedule and daily inspections. The following recommendations have been proven to be the most effective means of deterring contamination.
1. Pre-process colored zirconia units in a Toaster or laboratory oven at 275°C for 1 hour, prior to placing them in the sintering oven, make sure the Crows & Bridges are dry thoroughly. Heat lamps are not recommended as they differ in temperature and have been proven to be ineffective.
2. Visually Inspect heating elements prior to sintering.
3. Run regular decontamination monthly purge/element regeneration cycles on your oven to rid the elements of oxidation and regenerate its naturally occurring silica oxide layer.
4. Keep the oven clean and clear of debris.
5. Close the lift when not in use.
6. Replace sintering beads on a regular basis (minimum monthly recommended).
