National Dental Assisting Examining Board (NDAEB) Practice Exam

Which type of stain generally responds well to bleaching procedures?

1. Intrinsic Stain

2. Caffeine Stain

3. Extrinsic Stain

4. Tobacco Stain

The correct answer is: Caffeine Stain

Caffeine stains typically originate from foods and beverages that contain caffeine, such as coffee and tea. These stains usually adhere to the surface of the teeth rather than penetrate into the tooth structure. Because of this superficial nature, they tend to respond well to bleaching procedures, which target and lighten these extrinsic stains. When discussing intrinsic stains, which are within the tooth structure, their response to bleaching can vary and may not yield satisfactory results. Extrinsic stains, including those from sources like coffee or tobacco, may often respond positively to whitening treatments due to their location on the enamel surface. However, some extrinsic stains can be more resilient depending on their composition and how long they have been present. In summary, caffeine stains are well-suited for bleaching procedures because they are typically extrinsic and tend to be effectively lightened by bleaching agents designed to target surface discoloration.