A crown (or cap) is a covering that encases the entire tooth surface restoring it to its original shape and size. A crown protects and strengthens tooth structure that cannot be restored with fillings or other types of restorations.
Although there are several types of crowns, porcelain (tooth colored crown) are the most popular. They are highly durable and will last many years, but like most dental restorations, they may eventually need to be replaced. Porcelain crowns are made to match the shape, size, and color or your teeth giving you a natural, long-lasting beautiful smile.
An onlay restoration is similiar to a crown, but only covers a portion of the tooth. Hence, an onlay is sometimes called a partial crown. An onlay can be made of composite material, gold, or tooth-colored porcelain.
Onlays can be utilized to conservatively repair teeth that have large defective fillings or have been damaged by decay or trauma. Onlays are an ideal alternative to crowns (caps) because less tooth structure is removed in the preparation of onlays.
As with most dental restorations, onlays are not always permanent and may someday require replacement. They are highly durable and will last many years, giving you a beautiful long lasting smile.