Dental Shade Selection Techniques

Course Information

• Course Title: Clinical Fixed Prosthodontics V
• Course Code: PRO 325
• Topic of Lecture: Color science and shade selection
• Lecturer: Dr. Marwa Wahsh
• Post: Professor of Fixed Prosthodontics
• Faculty: Faculty of Dentistry
• Year: Fall 2024
• University: Galala University
• Partner University: Arizona State University

Color Matching

• Color matching is the process of selecting a shade of restorative material that matches the natural tooth color.

Visual Shade Matching

• Shade selection should be done quickly
• Glancing at a gray card can help rest the eyes
• Evaluate the entire shade guide
• Eliminate the worst match
• Moisten shade tabs and teeth; avoid dehydration

Shade Selection Sequence

• Seat the patient upright
• Observations should be quick
• Dentist should glance at a gray card to rest the eyes
• Scan the entire shade guide and eliminate the worst match
• Moisten shade tabs and teeth; avoid dehydration
• If a decision isn't possible, match the gingival portion; then the incisal portion
• Try viewing tabs through half-closed eyes to improve value matching

Shade Selection for Ceramic Laminate Veneers

• Take a photograph of the selected shade tab adjacent to the unprepared tooth structure;
• This photograph will serve as a reference shade for the technician.

Shade Selection for Stump

• Select the stump shade after the final tooth preparation.
• Restorations must compensate for a darker, higher chroma stump shade.
• Shade is frequently fabricated higher in value and lower in chroma in the correct hue.

Shade Guides

• Dentin shade guides are used to communicate the color of the prepared tooth when using translucent ceramic.

Shade Guide Systems

• Vita Classical. 1-4, 1 is least chromatic, 4 is most.
• Ivoclar Chromascop. 10-40, 10 is least chromatic, 40 is most.

Additional Information

• Higher numbers in the Vita classical shade guide are more chromatic, and lower numbers have a higher value (e.g., lighter).
• From left to right on the guide, chroma increases and value decreases.
• There are different groups classified according to hue; orange, yellow, yellow-grey, brown-grey
• Digitalized images assist in the process
• Color-measuring instruments like spectrophotometers are used.

Spot Capture Systems

• Vita Easyshade
• ShadeEye NCC
• Shade star

Complete-Tooth Capture Systems

• ShadeVision
• ShadeScan
• Digital image capture
• Windows-based analysis software

Digital Shade Selection

• The acquisition of photographs from a digital camera at standardized parameters
• Use gray card for white balance
• Use image-analyzing software (e.g., Adobe Photoshop CS) to calculate L*a*b* values.

ClearMatch

• Software used with digital cameras.
• Normalizes color images
• Contains all major shade guide systems
• Allows custom guides to be added.

Color Recording Using Smartphones

• Smartphones can record color parameters with a gray reference card.
• External LED Video Light is used for accurate image capture
• Selected shade tabs are positioned near the target tooth after color correction, increasing contrast and decreasing brightness for proper shade selection.
• Digital photographs of selected tabs are measured to determine the chroma.

IPS Shade Navigation App

• A series of steps for digital shade selection process utilizing a smartphone.

Limitations of Digital Shade Guides

• Technicians and clinicians require an understanding of color mapping techniques.
• Training is necessary for using these devices.
• Some devices do not cover the entire tooth surface.
• Some devices do not measure translucency, texture effects, and subsurface color.

This quiz covers essential techniques for dental shade selection, including how to prepare teeth and shade tabs before making a selection. Explore the features of advanced technologies like ShadeScan and digital shade analysis software. Test your knowledge on the color matching process in dentistry.