Answer: Yes even though the tooth is "covered" by a crown, it can still get a cavity. You can get a cavity around a crown much like you can around a filling. The reason is that the interface between the crown and the tooth, which dentists refer to as "margins" has potential to get decay, or collect food. While crowns do minimize the tooth fracturing and help decrease the chances of getting another cavity, decay can still form around the edges of the crown right around the gum line. Hygiene becomes especially important for brushing and flossing to prevent decay from developing.
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