When restoring a tooth with filling material is no longer an option, a crown will usually be required. Crowns reinforce the tooth structure to ensure prevention of further damage which can cause an individual to lose their tooth altogether.
Crowns are typically needed when decay has damaged a significant portion of the tooth, or when a large portion of the tooth has been worn down or broken due to trauma, grinding or clenching.
Crowns can be comprised of different materials including metal (usually gold), porcelain fused to metal or just porcelain. Porcelain fused to metal crowns and porcelain crowns provide better aesthetics than metal crowns as they can be matched to your natural tooth color. One difference, however, is that porcelain fused to metal crowns have a slightly noticeable metal sub-structure (a dark line which will appear near the gum line over time). Porcelain crowns do not contain this sub-structure and therefore give the appearance of a natural looking tooth. All porcelain crowns are a great option when a crown is required for a front tooth.
The first appointment for a crown preparation is to reduce and shape the tooth. Once it has been properly shaped, your dentist will take an impression of the reduced tooth. In most cases, the dentist will do this using an impression material (a putty-like material that is pressed onto the tooth which then sets). This is then sent to a dental laboratory where the crown will be fabricated.
As an alternative, the dentist may take an optical impression using an Itero® machine (this results in a digital, 3D image of your tooth which will then be emailed to the dental labratory). The dentist will make a temporary crown for you to wear for the two weeks prior to the cementation appointment. This temporary crown is made in the dental office. It is important that the temporary crown be worn during this period to prevent the adjacent teeth from shifting as the reduced tooth structure is no longer holding the opposing teeth in place.
The permenant crown will arrive back from the lab in two weeks at which time the cementation appointment will be required.