All of the Following Tooth Stains Can Be Removed by Scaling

question 21

Multiple Choice

All of the following tooth stains can be removed by scaling or selective polishing except which one?

• A) Chromogenic bacteria stain
• B) Extrinsic tooth stain
• C) Intrinsic tooth stain
• D) Chlorhexidine gluconate and cetylpyridinium chloride stain

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Definitions:

Degradation

The process by which a compound is broken down or decomposed, often into simpler substances, sometimes leading to a loss of quality or function.

mRNA

Messenger RNA (mRNA) is a type of RNA that carries genetic information from DNA to the ribosome, where it directs the synthesis of proteins.

Deoxyribose

Pentose sugar lacking a hydroxyl (—OH) group on carbon-2′; a constituent of DNA.

Hydroxyl Group

A functional group consisting of an oxygen atom bonded to a hydrogen atom (-OH), which is found in alcohols and many other organic molecules.