CDC CDC Shade Matching & Color Science 2

Question 1

In the context of dental ceramics, what does 'value' refer to?

Accepted Answer

The relative lightness or darkness of a color

Answer

The intensity or saturation of a hue

Answer

The dominant wavelength of the ceramic's color

Answer

The degree of fluorescence under UV light

Question 2

Which technique involves converting a shade photograph to grayscale to help the ceramist focus on value rather than hue during shade analysis?

Accepted Answer

Desaturation grayscale conversion

Answer

Polarized photography

Answer

Macro ring-flash photography

Answer

Cross-polarization filtering

Question 3

What is the recommended viewing distance when evaluating shade either chairside or in the laboratory?

Accepted Answer

Approximately 25 to 36 inches at arm's length

Answer

6 to 10 inches for close inspection

Answer

Greater than 5 feet

Answer

Distance is irrelevant if good lighting is used

Question 4

Which phenomenon causes the dental ceramist to perceive an afterimage of the complementary color when staring at a shade tab for too long?

Accepted Answer

Chromatic adaptation or color fatigue

Answer

Simultaneous color contrast

Answer

Bezold-Brucke effect

Answer

Purkinje shift

Question 5

Internal characterization in dental ceramics most commonly involves which step in the layering workflow?

Accepted Answer

Applying pigmented powders or stains within dentin or enamel layers before a final build-up firing

Answer

Painting external stains on the glazed surface

Answer

Adding opaque wash layers over the metal coping

Answer

Injecting tinted resin into pores after sintering

Question 6

What is the purpose of adding fluorescent pigments to dental ceramic powders?

Accepted Answer

To mimic the natural blue-white fluorescence of tooth structure under UV and visible light, enhancing vitality

Answer

To increase the opacity of the restoration under operatory lights

Answer

To improve bond strength to the resin cement

Answer

To lower the firing temperature of the ceramic