Koran A, Powers J M, Lepeak P J, Craig R G
J Dent Res. 1979 May;58(5):1455-60. doi: 10.1177/00220345790580050401.
The resistance of three silicone and one polyvinyl chloride maxillofacial materials to staining by tea, lipstick, and disclosing solution was measured by reflectance spectrophotometry. Changes in color caused by staining were larger than changes caused by color instability of the base elastomers or pigments under conditions of accelerated aging.