Shade guides

1. Shade guides • Shade tabs • - Each shade guide consists of multiple shade tabs

2. Vita Lumin Vacuum • Step 1: Hue matching • - Four grouping of hue, • A1-A4 Reddish-Brownish • B1-B4 Reddish-Yellowish • C1-C4 Grayish shades • D2-D4 Reddish-gray • - Match the samples with high chroma with cervical area of canines

3. Vita Lumin Vacuum • Step 2: Chroma selection • Once the hue has been accomplished, a choice is made for the best chroma • - For instance B is the best hue match then it has four different chroma: B1, B2, B3, B4, of the same hue

4. Vita Lumin Vacuum Step 3: Value selection - Finally, value is determined with a second commercial guide whose samples are arranged in increasing lightness (B1-C4) - An observer will be able to assess the value most effectively by observing from a distance, standing slightly away from the patient, and looking through a squinted eye, reducing the light that reaches the retina. Stimulation of the cones is reduced and greater conditions to achromatic vision may result

5. Vita Pan 3D Master • There are 5 lightness levels (plus an additional level for bleached teeth)

6. Vita Pan 3D Master Step 1:Value - Select one out of the 5 value groups

7. Vita Pan 3D Master Step 2:Chroma - Choose the appropriate chroma by using the M subgroup first and choosing between level 1, 2 or 3

8. Vita Pan 3D Master • Step 3: Hue • Choose the appropriate hue by choosing either more reddish (R) or more yellowish (L) • - Available in two chroma for group 2, 3 & 4

9. Shade guides • Other available systems, • - Extended shade guides • - Dentin shade guide • - Custom shade guide

10. Instrumental color analysis • Inconsistencies can result from factors such as physiological, psychological, age & fatigue • Instrumental color analysis is an alternative offering objective, quantifiable & more rapidly obtained shade matching • Various color measuring instruments exist: colorimeters, spectrophotometer, and digital image analyzers

11. Instrumental color analysis • Colorimeters, spectrophotometer are unsuitable for routine dental use because of their limited ability to measure the color of translucent objects • In addition, colorimeters are adapted for flat surfaces and not curved teeth surfaces

12. Instrumental color analysis

13. Surface characterization • Stains can be added to the surface of the restoration to produce better tooth integration & natural appearance • Used only for minor changes, to achieve: • 1. Shade modification • 2. Specific characterization • 3. Special illusions of form or position

14. Shade distribution chart • The tooth is divided into three regions: cervical, middle & incisal

15. Surface characterization • Advantages • Dentist can modify the shade after completion of the restoration • Disadvantages • - Stains are applied to the surface only (unrealistic) • If excessive can cause loss of fluorescence & • increased metameric effect • - Restoration becomes slightly rougher • - Stains are soluble & wear with time

16. Shade modification • a. Chroma & Hue adjustments • Increasing chroma and changing hue • Pink purple moves yellow toward yellow red, yellow decreases red to yellow red • If we desire to decrease the chroma we usually use the complementary colors (yellow requires blue-purple & orange, blue-green) however rarely successful

17. Shade modification • b. Value adjustments • Can be reduced by adding complementary color (violet for yellow) • Increase the value if the dominant color has a greater lightness such as staining with white but the opacity will increase & rarely successful

18. Specific characterization • Hypocalcified areas • Proximal colorations • Enamel cracks • Stained crack lines • Exposed incisal dentin • Incisal halo • Translucency

19. Specific characterization

20. Thank you