Dental crowns preserve the functionality of damaged teeth. Crowns may be used to protect a cracked tooth, restore the functionality of a tooth with excessive decay, or cover a tooth that has had root canal treatment. The purpose of a dental crown is to encase a ’weak’ tooth with a custom-designed material.
The three most common choices for materials for crowns are:
Porcelain fused to metal.
The material selected is determined by aesthetic requirements, strength & durability needs, and available space.
All-Ceramic Crowns (All porcelain)
The material most commonly used for all-ceramic crowns today is either zirconia or aluminous materials. They provide a metal-free aesthetic option with a number of benefits. By eliminating the need for the supportive metalcore, these crowns can be created with a thinner material. This makes them more favorable in areas with limited space. Additionally, the elimination of the metal core allows for light transmission through the porcelain for better optical, life-like properties. All-ceramic materials continue to improve, but caution should still be exercised for areas of the mouth subject to extreme forces like molars.
Although not as popular for aesthetic reasons, gold crowns are still preferred in some instances. Patients with strong bites and those who grind or clench their teeth might be better off with a gold crown. Gold crowns offer a level of strength and durability for teeth located in the back of the mouth, where they will not be as visible. Gold also tends to be less abrasive to the opposing tooth than porcelain. This helps to prevent wearing of the teeth.
Porcelain-fused-to-metal crowns provide an option that is strong, durable, and still provides the desired real tooth look. Due to the added thickness of material required to produce this type of crown, preparation of the tooth below is critical to ensure adequate space. One thing to consider before choosing the porcelain-fused-to-metal crown is that these crowns may tend to show the underlying metal or gold margin at the gum line as gums recede over time. Patients may opt for this type of crown and then at a later date if the aesthetics become an issue change to an all-ceramic crown.