Crowns are laboratory made, custom-fit restorations that are considerably stronger than regular filling materials. They are used when you have a tooth that has been heavily broken down (either through wear and tear, fractures or decay) and needs to be protected from further damage. They are also used for aesthetic purposes when you wish to alter the colour, shape or position of a tooth or multiple teeth. If your dentist recommends a crown, it's probably to correct one of these issues. Your dentist's primary concern, like yours, is helping you keep your teeth healthy and your smile bright.
Crowns may be made from several materials, including gold, porcelain with metal, or porcelain only (see image below). Each material is used for different situations so speak to your dentist about which type of crown will benefit you most.