A crown is a cover, or "cap," that restores a tooth to its normal shape and size. The secondary effect of this is that it strengthens and improves the appearance of the tooth.

Crowns can become necessary when a tooth is broken down to the extent that a filling won't solve the problem.

Crowns are also needed to stop further damage to a cracked tooth by holding it together.

Also, if there is not enough of a tooth to support a filling, Crowns are used to restore it.