Lecture 4 - Optical properties and shade determination

What is transillumination?

a) The emission of light at a different wavelength

b) A method to measure color density

c) Examination of a tissue by passing strong light through it

d) Reflection of light of shorter wavelengths

c) Examination of a tissue by passing strong light through it

What are the three-dimensional characteristics of color?

a) Hue, saturation, brightness

b) Hue, chroma, value

c) Lightness, vitality, density

d) Red, green, blue

b) Hue, chroma, value

What is metamerism?

a) The reflection of light of shorter wavelengths

b) Color matching under all light sources

c) Change in the color of objects under different light sources

d) A measure of permeability to electromagnetic waves

c) Change in the color of objects under different light sources

Which group in Vita Classic has dominant red and brown colors?

a) Group A

b) Group B

c) Group C

d) Group D

a) Group A

How many colors are included in Vita Classic?

a) 12

b) 16

c) 24

d) 26

b) 16

What is fluorescence?

a) Emission of light at the same wavelength as incident light

b) The reflection of electromagnetic waves

c) Emission of light at a different wavelength from the incident light

d) A method of visualizing caries

c) Emission of light at a different wavelength from the incident light

How is the tone in the 3D Master system changed?

a) Vertically

b) Horizontally

c) Radially

d) Diagonally

b) Horizontally

What is the optimal distance for color registration?

a) 15 cm

b) 20 cm

c) 25 cm

d) 30 cm

c) 25 cm

Which shade guide uses a two-step process for color registration?

a) Vita Classic

b) Vita 3D Master

c) Linear Guide

d) Chromascop

c) Linear Guide

What is the light source requirement for color temperature?

a) 5400K

b) 5500K

c) 5800K

d) 6000K

b) 5500K

What is an isomeric pair in color matching?

a) Objects that match color under specific light

b) Objects that are matched under all light sources

c) Objects reflecting shorter wavelengths

d) Objects transmitting longer wavelengths

b) Objects that are matched under all light sources

What is the opal effect?

a) Reflection of light of shorter wavelengths and transmission of longer wavelengths

b) Transmission of light of shorter wavelengths and reflection of longer wavelengths

c) Light matching under variable conditions

d) Emission of light at a different wavelength

a) Reflection of light of shorter wavelengths and transmission of longer wavelengths

Transparency is defined as:

a) Reflection of electromagnetic waves

b) A measure of permeability to electromagnetic waves or radiation

c) The absorption of light into a material

d) A method to match tooth color

b) A measure of permeability to electromagnetic waves or radiation

How many tabs and groups are there in the 3D Master shade guide?

a) 20 tabs, 4 groups

b) 26 tabs, 5 groups

c) 15 tabs, 3 groups

d) 24 tabs, 6 groups

b) 26 tabs, 5 groups

What are the three designations in the Vita 3D Master?

a) Hue, chroma, value

b) Number bands, tone values, saturation levels

c) Red, blue, green

d) Light intensity, reflectivity, chromatic levels

b) Number bands, tone values, saturation levels

What is the total number of shades in the Vita Bleachguide 3D Master?

a) 24 shades

b) 16 shades

c) 29 shades

d) 20 shades

c) 29 shades

Which group in the Chromascop shade guide corresponds to yellow?

a) Group 100

b) Group 200

c) Group 300

d) Group 400

b) Group 200

What is the light source requirement for CRI index?

a) 70

b) 80

c) At least 90

d) At least 100

b) 80

What is the light intensity requirement for lab lighting?

a) 18,000 lux

b) 28,000 lux

c) 50,000 lux

d) 35,000 lux

c) 50,000 lux

Which shade guide uses "hue" as the leading dimension?

a) Vita Classic

b) 3D Master

c) Linear Guide

d) Spectroshade

a) Vita Classic

What are the four gingival colors?

a) Pink, red, grey, white

b) Light pink, medium pink, medium dark pink, dark pink

c) Light red, yellow, grey, dark red

d) Red, orange, brown, grey

b) Light pink, medium pink, medium dark pink, dark pink

Which variable changes vertically in the Vita 3D Master system?

a) Tone

b) Saturation

c) Value

d) Hue

b) Saturation

The optimal color-registration time is:

a) 10 seconds

b) 15–20 seconds

c) 30 seconds

d) 5 minutes

b) 15–20 seconds

What is the light source requirement for cabinet light intensity?

a) 10,000 lux

b) 15,000 lux

c) 18,000–28,000 lux

d) 28,000 lux

c) 18,000–28,000 lux

Which shade guide emphasizes value as its leading dimension?

a) Vita Classic

b) 3D Master

c) Bioform

d) Chromascop

b) 3D Master

How many color standards are there in Bioform?

a) 12

b) 16

c) 20

d) 24

d) 24

How many stages are involved in the Vita Linear Guide color registration process?

a) 1

b) 2

c) 3

d) 4

b) 2

What is the recommended time for color registration?

a) 8 AM to 10 AM

b) 10 AM to 2 PM

c) 2 PM to 6 PM

d) 12 PM to 4 PM

b) 10 AM to 2 PM

What is the optimal distance for color registration?

a) 20 cm

b) 25 cm

c) 30 cm

d) 35 cm

b) 25 cm

What are primary colors?

a) Red, green, blue

b) Yellow, red, blue

c) Cyan, magenta, yellow

d) Yellow, orange, green

b) Yellow, red, blue

What colors are included in CMYK?

a) Red, green, blue, black

b) Cyan, magenta, yellow, key (black)

c) Cyan, yellow, orange, black

d) Cyan, green, red, black

b) Cyan, magenta, yellow, key (black)

What equation relates speed, wavelength, and frequency?

a) v = λ + f

b) v = λ × f

c) v = f / λ

d) v = λ / f

b) v = λ × f

What is the primary application of transillumination?

a) Shade matching

b) Visualization of approximal caries

c) Measuring fluorescence

d) Determining opacity

b) Visualization of approximal caries

Which color space group in Vita Classic is grey?

a) Group A

b) Group B

c) Group C

d) Group D

c) Group C

What instrument measures the amount of light reflected from a surface in intervals over the visible spectrum?

a) Spectrophotometer

b) Colorimeter

c) Fluorometer

d) Transilluminator

a) Spectrophotometer

Which tool takes 3–5 measurements and averages the results?

a) Spectroshade Micro

b) Vita Easyshade Compact

c) ShadeEye NCC

d) Linear Guide

c) ShadeEye NCC

What components make up a colorimeter?

a) Light source, detector, filters

b) Spectrometer, analyzer, display

c) Lens, screen, wavelength modulator

d) Sensor, LED, mirror

a) Light source, detector, filters

How is the tone of the 3D Master system modified?

a) Horizontally

b) Vertically

c) Radially

d) Diagonally

a) Horizontally

What is the leading sign of Vita 3D Master?

a) Hue

b) Fluorescence

c) Bleaching

d) Opacity

c) Bleaching

What is the light intensity requirement for the laboratory?

a) 18,000 lux

b) 28,000 lux

c) 35,000 lux

d) 50,000 lux

b) 28,000 lux

How many tabs and shades are included in Vita Bleachguide 3D?

a) 10 tabs, 20 shades

b) 15 tabs, 29 shades

c) 20 tabs, 24 shades

d) 25 tabs, 30 shades

b) 15 tabs, 29 shades

What are the indices for whitening in Vita Bleachguide 3D?

a) Indices 0 to 5

b) Indices 1 to 10

c) Indices M1 to M5

d) Indices W1 to W3

a) Indices 0 to 5

What does the Vita Easyshade Compact display?

a) Measurement speed

b) Test results

c) Calibration accuracy

d) Light intensity

b) Test results

Which complementary colors create grey when mixed?

a) Red and blue

b) Green and magenta

c) Equal proportions of complementary colors

d) Cyan and yellow

c) Equal proportions of complementary colors

How many colors are in Vita Classic?

a) 14

b) 15

c) 16

d) 18

c) 16

What property helps visualize caries with a transillumination method?

a) Reflection

b) Transparency

c) Translucent zone creation

d) Chroma

c) Translucent zone creation

What feature combines a digital image with spectrophotometric analysis?

a) ShadeEye NCC

b) Spectroshade Micro

c) Vita Easyshade Compact

d) Bioform

b) Spectroshade Micro

What are the groups of the Chromascop shade guide?

a) 100–White, 200–Yellow, 300–Light Brown, 400–Grey, 500–Dark Brown

b) A–Red, B–Yellow, C–Grey, D–Brown

c) 1–Light Pink, 2–Pink, 3–Dark Pink

d) X–Light Grey, Y–Medium Grey, Z–Dark Grey

a) 100–White, 200–Yellow, 300–Light Brown, 400–Grey, 500–Dark Brown

What instrument is slower but more accurate: spectrophotometer or colorimeter?

a) Spectrophotometer

b) Colorimeter

a) Spectrophotometer

What are the color values for summer and winter light temperatures?

a) Summer 5400K, Winter 5800K

b) Summer 5800K, Winter 5400K

c) Summer 5000K, Winter 6000K

d) Summer 6000K, Winter 5000K

b) Summer 5800K, Winter 5400K

On the Munsell value scale, what is the recommended ceiling color value?

a) 6

b) 7

c) 8

d) 9

d) 9

What is the recommended wall and worktop color value on the Munsell scale?

a) 6

b) 7

c) 8

d) 9

b) 7