*To restore a tooth to its original shape.
*To strengthen a tooth.
*To improve the cosmetic appearance of a tooth.
The strengthening capability of dental crowns is related to the fact that they cover over and encase the tooth on which they are placed, thus serving as a splint which binds the tooth together. Dental crowns are a very important means by which a dentist can strengthen a tooth.
In contrast, dental fillings, especially large ones, often have a weakening effect on the teeth in which they are placed. Dental fillings rely on a tooth's remaining structure to hold and support them. Fillings, in general, don't strengthen a tooth and don't protect a tooth from the forces generated by biting and chewing.