What is a characteristic of intrinsic stains?

Intrinsic stains are characterized by their inability to be removed from the tooth surface through traditional methods such as polishing. These stains originate from within the tooth structure itself, often due to factors such as developmental issues, medication effects (like tetracycline), or certain medical conditions. Because they are embedded within the enamel and dentin layers, intrinsic stains require more advanced cosmetic procedures, such as whitening treatments or veneers, to address them, unlike extrinsic stains which can typically be polished away.

The other characteristics listed highlight different aspects of tooth staining. Removable stains are generally extrinsic, typically caused by environmental factors such as food and beverages, which do not penetrate the tooth structure. Intrinsic stains do not fall into this category. Additionally, while intrinsic stains may be cosmetic, they often indicate a deeper issue and their treatment can go beyond purely cosmetic reasons, aiming for both aesthetic and structural integrity of the tooth.