Tooth discoloration Light hitting a tooth undergoes reflection, absorption and transmission by varying degrees in each tissue layer of the tooth substance. Reflected light detected by the human eye determines the perceived appearance of a tooth. Teeth have a thin enamel layer on the outer surface. The enamel layer is whiter and semitransparent, and contributes blue, pink green tints to the tooth color. The underlying dentin layer is darker than enamel, yellow-brown in color, and less transparent. Dentin forms the bulk of the tooth substance, and contributes most to the overall tooth color. At the core of the tooth is soft connective
Dental material deep undercuts). In order to obtain an accurate impression, a suitable property of impression material must be used. Impression materials are designed to be liquid or semi-solid when first mixed, then set hard in a few minutes, leaving imprints of oral structures. Common dental impression materials include: Historically these products were used as impression materials: Dental lining materials are used during restorations of large cavities, and are placed between the remaining tooth structure and the restoration material. The purpose of this is to protect the dentinal tubules and the sensitive pulp, forming a barrier-like structure. After drilling the caries out