Which type of stains can be effectively removed by coronal polishing?

Coronal polishing is primarily effective for the removal of extrinsic stains, which are surface stains that accumulate on the teeth from external sources like food, beverages, tobacco, and poor oral hygiene. These stains reside on the outer enamel and can be polished off using abrasive agents during coronal polishing procedures.

In contrast, chlorhexidine stains, while they may be extrinsic in nature, are specifically associated with the use of chlorhexidine mouth rinses and require more specialized removal techniques beyond standard coronal polishing, often needing professional cleaning or remedial treatments.

Intrinsic stains, which are embedded within the tooth structure itself due to factors like developmental conditions or past traumas, cannot be removed through coronal polishing. They require more advanced cosmetic or restorative dental procedures to treat.

The option stating that all types of stains can be effectively removed is also inaccurate, as intrinsic stains cannot be addressed through coronal polishing. Therefore, the most accurate understanding is that coronal polishing is indeed effective for extrinsic stains, while specific stains, such as those caused by chlorhexidine, may need targeted methods for removal.