Tips for Shade Selection (ref. 4)
Take the shade at the beginning of the patient's diagnostic appointment. Confirm shade selection at the preparation appointment (see Figure 1a). Dehydrated teeth appear more white and opaque than hydrated teeth (see Figure 1b).

Figure 1a. Dehydrated teeth.

Figure 1b. Hydrated teeth.
Glance at the teeth. The longer you look at the teeth the more gray they appear.
Select a room with neutral colored walls.
4. Ensure a proper light source:
Indoor - color-corrective light source
Outdoor - Northern-exposure sunlight during midday (slightly overcast) optimum
Look to the gingival third of the tooth for the base shade. The incisal edge of the tooth is often translucent, and the cervical 1/3 of the tooth may be stained. (see Figure 2)

Figure 2.
Intraoral photographs communicate color variations and tooth characterization.
Have two people take the shade to confirm accuracy.
A gray card next to the teeth helps neutralize extraneous light and isolate the tooth.
Work Order (including Shade map) (see Figure 4)
10. Tooth whitening (or bleaching) products will not lighten composite or porcelain restorations.

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