The terminology surrounding dental restorations can be confusing, particularly when patients hear terms like “crown” and “cap” used interchangeably. This ambiguity often leads people to wonder if these restorations are different or if they serve distinct purposes. Understanding the nature of a dental crown, the reasons a dentist might recommend one, and the process of receiving this treatment is important for anyone considering restorative dental care.
Understanding the Terminology
There is no functional or physical difference between a dental crown and a dental cap; they both refer to the exact same dental restoration. The term “crown” is the formal, professional terminology used by dentists and dental laboratories. A dental crown is a tooth-shaped covering permanently cemented onto a prepared tooth, encasing the entire visible portion above the gum line.
The term “cap” is simply a colloquial term that patients and the general public frequently use. This nickname comes from the restoration’s function, as it literally “caps” or covers the whole tooth structure to restore its original shape, size, and strength. While dental professionals prefer “crown,” both words refer to this full-coverage restoration.
Reasons for Needing a Crown
A dentist recommends a crown when a tooth requires structural support or complete restoration that a standard filling cannot provide. A primary reason is to protect a tooth that has undergone a root canal procedure, as these teeth can become brittle and susceptible to fracture. Crowns are also necessary for restoring teeth with extensive decay or those with a very large filling, where insufficient natural tooth structure remains.
A crown can prevent a severely cracked or fractured tooth from breaking apart, reinforcing the remaining pieces and sealing the tooth from bacteria. Crowns are also used for cosmetic improvements, such as covering severely discolored, misshapen, or worn-down teeth. Additionally, they serve as the final restoration placed on top of a dental implant or as an anchor for a dental bridge.
The Procedure for Receiving a Crown
Receiving a permanent dental crown typically involves two separate appointments spaced about two weeks apart, allowing time for custom fabrication. During the first visit, the dentist administers a local anesthetic to ensure the area is numb. The tooth is then meticulously reshaped by removing a small amount of enamel, which creates the necessary space for the crown to fit without appearing bulky.
After preparing the tooth, the dentist takes an impression of the reshaped tooth and surrounding teeth, using either a putty-like material or a digital scanner. This impression is sent to a dental laboratory, where technicians fabricate the custom-fitted crown. A temporary crown made of resin or acrylic is placed over the prepared tooth to protect it and maintain the space until the permanent crown is ready.
The second appointment begins with the removal of the temporary crown and a thorough cleaning of the underlying tooth. The dentist places the permanent crown to check its fit, bite alignment, and color match with adjacent teeth. If all parameters are satisfactory, the crown is permanently secured to the tooth using a strong dental cement, finalizing the restoration.
Materials Longevity and Maintenance
Dental crowns are made from several materials, with the choice depending on the tooth’s location and the patient’s aesthetic preference. Common materials include all-ceramic (porcelain or zirconia), which offers the best natural appearance, or metal alloys and porcelain-fused-to-metal (PFM) for greater strength in back teeth. Metal crowns, particularly gold alloys, are known for exceptional durability and can last 15 to 30 years or more.
The typical lifespan for dental crowns ranges from 5 to 15 years, a period influenced by the material chosen and the patient’s oral hygiene habits. To maximize longevity, patients should maintain a daily routine of brushing twice a day and flossing around the crown to prevent decay at the margin. Avoiding habits like chewing on ice, hard candy, or non-food objects is important, as this can lead to fracturing the porcelain.