How to Get Accurate Shade Readings

The quality of your shade match depends entirely on the quality of your photo. Follow these clinical best practices for reliable results.

Most important: The tooth and shade tabs must be under the exact same light at the same distance from the camera. Any difference in lighting or distance will invalidate the comparison.

Step-by-Step Guide

1

Prepare your shade guide

Select 3–5 tabs that bracket your expected match. For example, if you think the tooth is around A2, include A1, A2, A3, and maybe B2. Lay them on a clean, non-reflective surface.

2

Position tooth and tabs together

Have the patient open wide enough that the target tooth and all shade tabs fit in one frame. The tabs should be as close to the tooth as possible — ideally touching or nearly touching. This ensures identical lighting.

3

Control the lighting

Use consistent, neutral illumination:

  • Daylight (5000–6500K) is ideal — near a window (but not in direct sun) or with a daylight-balanced LED
  • Avoid operating lights — they're too blue and create glare
  • Avoid warm incandescent — too yellow, distorts shade
  • Avoid mixed lighting — daylight plus overhead creates metamerism
4

Capture the photo

Hold the camera parallel to the tooth (not at an angle). Fill the frame with the tooth and tabs — you'll crop later. Take several shots and pick the sharpest one with the least glare.

5

Crop to the working area

In the tool, drag a crop box around just the tooth and shade tabs. This eliminates distracting background and focuses the analysis on the relevant area.

6

Draw the tooth circle

Tap the middle third of the tooth to drop a circle. Drag the corner to size it so it covers only enamel — no gum, no edges, no glare. This is your reference color.

7

Draw shade tab circles

Tap each shade tab to add circles. Again, aim for the middle of each tab surface. The tool will instantly calculate ΔE00 and similarity percentage for each.

8

Read the results

The best match is highlighted in gold. The "Best" chip shows which tab won and its similarity score. If it's not perfect, the result card will suggest which direction to go (e.g., "higher Value, more Chroma").

Using 3-Zone Mode

For comprehensive documentation, toggle to 3 zones mode (the Single/3 zones button in the toolbar). This analyzes the cervical, middle, and incisal thirds separately:

1

Switch to 3 zones

Tap the 3 zones button in the toolbar. Any existing tooth circles will be cleared.

2

Draw the three tooth zones

The tool will guide you through placing circles on each third:

  • Cervical: Near the gum line — tap this area first
  • Middle (body): The main body of the tooth — this drives your shade tab selection
  • Incisal: The biting edge — translucent and lighter; tap this last
3

Add shade tabs as usual

After mapping the tooth thirds, tap each shade tab to add circles. The tool will match each zone independently and display a shade map showing the best match for cervical, body, and incisal thirds.

Pro tip: The middle third is your reference for the shade guide. Cervical and incisal readings help the lab understand translucency and characterization, but the body shade is what you match to the guide.

Understanding the Numbers

After you've drawn your circles, the tool will show results. For detailed explanations of ΔE00 scores and similarity percentages, see the About page.

Common Mistakes to Avoid

✓ Do This

Tooth and tabs in the same frame under identical lighting. Tabs nearly touching the tooth. Neutral daylight illumination. Camera parallel to tooth surface.

✗ Don't Do This

Separate photos of tooth and tabs. Different distances from camera. Mixed lighting sources. Camera at an oblique angle. Glare on tooth or tab surfaces.

Troubleshooting

High spread warning? If a circle shows a spread value above 7.0, it's covering mixed surfaces — move or shrink it until the warning disappears.

Glare or shadow in the circle? Even after the trimmed-mean algorithm removes the worst pixels, strong glare can skew results. Reposition the circle away from reflections.

Tooth wet vs. dry? A wet tooth looks different than a dry tooth. For consistency, document teeth in their natural state — slightly moist from saliva, not freshly dried and not pooled with water.

Ready?

Follow these principles and your shade matches will be consistent and defensible. The tool gives you the numbers — your clinical judgment interprets them.

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