What Is a Dental Crown?

Are crowns necessary | Dental crown premolar tooth assembly process.illustration | My Dental Advocate

Dr Advocate Avatar IconBy: Dr. Advocate
Updated: January 30, 2023

A tooth is an amazing structure and serves a critical role – in helping us eat! If you lose part of a tooth through a cavity or tooth fracture, they don’t regrow, and untreated can affect chewing and eating enjoyment. That’s where crowns come in. Crowns, or caps, are tooth-like solid replacements that protect from wear, fracture, or discoloration. There are many types of crowns, and each has a functional purpose.

After root canals, crowns are predominantly required to protect the weak and brittle remaining tooth structure. Because the nerve tissue provides nutrients to the tooth, the tooth requires reinforcement for longevity and durability after the nerve is removed. Sometimes, crowns are needed if large fillings fracture, cavities form under existing crowns, or the original crown fits poorly, causing hot or cold sensitivity. If the cavitation is too large, there may not be enough tooth remaining to support a subsequent filling.

Crowns are also fastened to implants to restore function and prevent adjacent teeth from drifting into the space. Lastly, crowns can also be used to mask imperfections or discolorations for esthetic purposes.

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What happens during treatment?

Before committing to treatment, be sure you understand why you need a crown. Did the tooth need a root canal? Does the tooth have a cavity that’s too large for a filling? Did your filling fracture? Also, discuss with your clinician treatment alternatives, such as a bridge if an adjacent tooth is missing, or extraction is more cost-effective if you are financially limited.

Central Incisor preparation process for dental crowns or Veneer placement | My Dental Advocate

After administering the anesthetic, the clinician will verify that you’re adequately numb. Due to the dense cortical bone, it takes longer for the lower teeth to numb than the porous maxillary jaw. If you have issues keeping your jaw open during procedures, ask the dental assistant for a bite block to rest your jaw open.

The clinician will first remove minimal tooth structure from all surfaces so that the crown fits snugly and will not interfere with your bite or adjacent teeth upon delivery. The amount of tooth structure that’s removed depends on the type of crown being placed. For example, porcelain fused to metal (PFM) and ceramic crowns requires more tooth structure removal than zirconia or gold crowns. After removing the cavity or existing filling, the dentist will place a build-up to replace the missing tooth structure.

After the tooth is prepared, an impression will be taken conventionally (gooey material) or digitally. The dentist can accurately take a digital scan if a ceramic or zirconia crown is planned, followed by design, fabrication, and delivery. If the digital scan is unsatisfactory, the clinician can quickly re-scan the tooth until it’s satisfactory.

Digital, same-day crowns are efficient, cost-effective, and no temporary crown is needed. A temporary crown will be fabricated after the impression is inspected and approved if a conventional impression is required. Avoid crunchy and sticky foods until your final crown is delivered. Crown fabrication will take 1-4 weeks, depending on the laboratory and desired crown material.



What crown material is best?

Crown materials have evolved over the years. Gold and PFM crowns have been preferred for decades because of their strength and predictability. However, ceramic and zirconia crowns have grown in popularity because of their strength and predictability. Let’s compare the four most common types of crowns.

Gold

Pros

  • Minimal tooth structure removed
  • Non-abrasive to opposing teeth
  • Cleansable/difficult for plaque to adhere
  • Strong and durable
  • Best for posterior teeth

Cons

  • Requires conventional impression
  • Requires temporary crown
  • Requires second visit
  • Unsightly
  • Prone to wear if gold content is high

Porcelain fused-to-metal (PFM)

Pros

  • Inexpensive
  • Only 1 or 2 impressions needed
  • Successful track record
  • Esthetically pleasing

Cons

  • Prone to fracture
  • Abrasive to opposing teeth
  • Metal allergy is possible
  • Requires conventional impression
  • Requires temporary crown

Ceramic

Pros

  • Most esthetic
  • Bonded for added strength
  • Same day delivery possible
  • Digital impression

Cons

  • Expensive
  • Technique sensitive
  • More tooth structure removed
  • Fractures are possible

Zirconia

Pros

  • Extremely strong
  • Same day delivery possible
  • Digital impression
  • Best for posterior
  • Bonded for added strength
  • Minimal tooth structure removed

Cons

  • Expensive
  • Abrasive to opposing teeth
  • Limited track record

Considerations

Dental crowns bridge of 3 teeth over molar and premolar illustration | Ceramic Dental Crowns are bestCeramic crowns are favorable because of their strength, aesthetics, and same-day delivery capability. Many clinicians are now equipped with a scanning machine that precisely scans the tooth after drilling is completed. Chairside scanning allows the clinician to digitally send the images to the lab or fabricate the crown in the office and deliver it within 2-3 hours. The clinician completely controls each step and can make modifications on the fly if an error arises.

Ceramic crowns are prone to fracture, though. Crown fractures happen if the fabricated crown is not thick enough in heavy load areas, which are often seen in the back of the mouth, particularly the molars, because of their lower height, high degree of bite force, and limited thickness crowns that can be applied there. In these cases, a zirconia crown would be better suited. Zirconia is the strongest type of crown material and can be digitally scanned. Gold is also a favorable option; however, a conventional impression is required, which may be uncomfortable for many patients.

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Final thoughts


Crowns are essential to repair and protect teeth. Unfortunately, they can be expensive, and understanding the different material options can make your head spin. Have you recently been diagnosed with needing a crown? Were you hoping a filling could be completed instead? My Dental Advocate’s team of board-certified dentists can provide a second opinion on your planned treatment. We look forward to bringing you peace of mind by verifying your treatment plan, suggesting an alternative, or just answering your questions.

The more you know, the more healthy habits you can develop, saving you and your family from avoidable and potentially expensive dental procedures. Talk to your dental professional for more suggestions on improving oral health and check back for more blog posts and relevant information. Please share this site and let us know what else you’d like to know!


Related topics

Cavities | Crowns | Extractions | Fillings | Root Canals | X-Rays


Dr Advocate Avatar IconAbout the Author

Dr. Advocate is a board-certified dentist with 5+ years of clinical practice experience on a mission to provide accurate dental patient education. He believes everyone should access easy-to-read dental resources presented in layperson’s terms with relevant, up-to-date dental research and insight to improve their oral health.