Which type of stains originate within the tooth structure?

Intrinsic stains are those that originate within the tooth structure itself. These types of stains can be caused by a variety of factors, including the presence of certain pigments during tooth development, exposure to certain medications (such as tetracycline), or trauma to the tooth that can create discoloration from within. Intrinsic stains typically cannot be removed through regular cleaning or polishing, as they are embedded within the enamel and dentin rather than merely residing on the surface of the teeth.

In contrast, extrinsic stains are surface stains that can occur due to external factors like food, drinks, poor oral hygiene, or tobacco use. These can often be removed through professional cleaning or improved oral hygiene practices. Exogenous stains refer to stains that come from outside sources, which are generally extrinsic in nature. The term "extrinsicoff staining" seems to be a typographical variation or error of "extrinsic staining" and does not denote a separate category.