Harvest Nano Sintering Best Practices

Modified on Tue, 12 Aug at 2:08 PM

A great starting point when sintering Harvest Nano for the first time

Calibrate your furnace – Check thermocouple regularly, use your manufacturer's instructions – suggested to be performed weekly.
Test fire 2–3 units at slightly different temps
Document results visually next to a shade tab.
Build a “shade map” for your furnace and puck brand.
Store these results in a binder or digital logbook for technician reference.

*Remember to adjust your parameter settings for cycles from your calibration readings

Perfect Shades are achieved with Peak Temperature Adjustments

The peak temp is one of the most influential parameters for shade results.

Problem	Solution	Why it Works
Final restoration is too dark	Increase peak temp by 5–10°C (up to safe limits for material)	Higher temps break down oxides and bring more lightness
Restoration is too light or washed out	Lower peak temp by 5–10°C	Lower heat preserves color saturation in pre-shaded zirconia
Gradient between layers is too flat	Try lower peak temp or shorten hold time	Prevents over-mixing of transition layer pigments

Your Peak Hold Time can effect color, consistency & translucency.

The dwell/hold time at peak temperature can either deepen or desaturate color.

Problem	Solution	Why it Works
Color seems muted/faded	Reduce hold time by 15–30 minutes	Long holds bleach out stains and pigments
Color is inconsistent between restorations	Ensure consistent hold time across batches	Variance in dwell = unpredictable chroma/shade
Need more translucency with same shade	Slightly increase hold time at high temp	Allows better crystal formation without color loss (only up to a point)

The speed of Ramp Rate (Heating)

The speed at which you ramp up to peak temperature can alter shade results subtly but meaningfully.

Problem	Solution	Why it Works
Crowns look patchy or have banding	Use slower ramp (especially up to 900°C)	Ensures even pigment activation and moisture removal
Final result looks dull	Slightly faster ramp post-1000°C	Can increase translucency but risks overshooting color

Cooling Rate effects the optics and translucency.

While less commonly adjusted, cooling also impacts final optical results.

Problem	Solution	Why it Works
Crowns appear milky or chalky	Slow down cooling from 1000°C to 400°C	Preserves crystal integrity and shade vibrancy
Not enough translucency	Try a more controlled, stepped cooldown	Helps tetragonal-to-cubic transitions stabilize properly

Placement Inside the Furnace can effect the balance of shade i

Uneven heating causes shade variation across units in the same run.

Problem	Solution	Why it Works
Units have different shades in same batch	Place all crowns in center zone and same tray height	Ensures consistent thermal exposure
One side of arch is lighter	Rotate or reposition next run	Furnace hot spots affect color and translucency

Use of Covers or Sintering Beads

Shade can be altered by how exposed your zirconia is to the furnace atmosphere.

Problem	Solution	Why it Works
Too much surface oxidation (greying or odd surface tone)	Use zirconia sintering cover, or alumina beads	Reduces oxygen exposure at high temps

Custom Sintering Profiles per Shade Group

Some labs build custom programs for A1–A3, B shades, etc.

Problem	Solution	Why it Works
A3s look too dark, A1s look too light	Slightly reduce temp for darker shades, raise for lighter	Keeps each shade family in its proper chroma/value