Silicone Materials & Color Matching Flashcards

Which method is most reliable for evaluating color match between a silicone prosthesis and patient skin under variable lighting conditions?

Answer: Spectrophotometric measurement combined with visual assessment under multiple standardized illuminants

Combining spectrophotometric objective data with visual evaluation under D50, D65, and incandescent illuminants minimizes metamerism-related errors.

What role does fumed silica play when added to medical-grade silicone for prosthetic applications?

Answer: Functions as a reinforcing filler to improve tensile and tear strength

Fumed silica is a reinforcing filler that significantly improves the tensile strength and tear resistance of silicone elastomers without substantially affecting hardness.

A silicone ear prosthesis appears lighter than the patient's skin when viewed outdoors but matches well indoors. This suggests the prosthesis has:

Answer: Insufficient UV-stable pigmentation causing differential reflectance outdoors

Outdoor light has higher UV and blue content than indoor artificial light; insufficient UV-stable pigmentation causes the prosthesis to appear lighter or different outdoors.

In the Kubelka-Munk theory applied to prosthetic color matching, what do the K and S coefficients represent?

Answer: Absorption coefficient (K) and scattering coefficient (S) of the colorant layer

Kubelka-Munk theory models paint/colorant layers by their absorption (K) and scattering (S) properties to predict resulting color appearance.

Which adhesive system is most compatible with medical-grade addition-cure silicone prostheses for facial retention?

Answer: Medical-grade silicone adhesives or acrylic-based prosthetic adhesives designed for skin contact

Medical-grade silicone or acrylic prosthetic adhesives are specifically formulated for skin biocompatibility and effective bonding without degrading the silicone prosthesis.

Why should pigment loading in silicone prostheses be kept below approximately 3-5% by weight?

Answer: Excess pigment acts as a filler that weakens the silicone matrix and reduces mechanical properties

Pigment particles above 3-5% by weight disrupt the silicone polymer network, reducing tensile strength, tear strength, and elongation at break.

When matching a prosthesis to sun-tanned skin, the anaplastologist should:

Answer: Match the untanned baseline skin tone to accommodate seasonal color changes

Matching the patient's baseline untanned skin tone ensures the prosthesis remains aesthetically appropriate year-round as seasonal tan fades.