What are Dental Crowns?
A dental crown is a device placed over the tooth, designed to resemble your real teeth. The cap completely covers the tooth to protect it from infection or damage. Crowns come in a wide range of materials including ceramic, metal alloys, porcelain, or composite resin. A crown also restores the function and aesthetics of your tooth.
An orthodontist will choose the most appropriate material and methodology depending on the desired outcome. For example, porcelain is an ideal option when you want a crown that complements the color of your teeth.
However, porcelain is not as durable as other alternative materials like metal. A dental specialist will discuss your preferences and concerns before fitting the crown.
Why Would You Need a Dental Crown?
The purpose of fitting a crown is to restore the teeth’s aesthetics and function. Patients with tooth decay may need a crown to protect the tooth from further damage. The crown holds the tooth together, preventing fractures from getting worse.
If your tooth is already fractured, the cap covers the tooth to reduce the risk of infection. The soft tissues inside the tooth can succumb to inflammation if the enamel is broken.
Crowns are essential for protecting a tooth whose metal filling is breaking down. The cap prevents tooth sensitivity when fractures on the enamel expose the dentin and pulp.
A dentist may recommend getting a crown after root canal treatment. The root canal procedure is an endodontic treatment to extract the tooth pulp to alleviate pain or address inflammation. An open pulp and dentin are more susceptible to infections.
A crown is usually necessary if you’ve had a tooth canal on your molars and premolars. The back teeth experience a lot of pressure when you bite or chew food. Therefore, they may need extra protection to restore your teeth’s functionality.
You may also need a crown after an implant or bridge procedure. The crown serves as the cap covering the prosthetic implanted into your gums. The crown holds false teeth into place, supporting the dental bridge.
Types of Dental Crowns
There are different types of dental crowns designed to address various teeth problems. Dental specialists have to consider several factors before fitting a crown.
- Color of your teeth
- Location of the tooth
- Extent of tooth damage or decay
- Condition of the surrounding gum tissue
- Porcelain Crowns
Porcelain is the most common material used for dental crowns. Porcelain is most often the best option for crowns on the front teeth because it complements the enamel.
Porcelain does not contain metals, making them biocompatible and free from toxins. They are ideal for patients that are allergic to metals or additives in other dental devices.
The disadvantage of porcelain is that it is not as durable as gold or metal. It may not be suitable for people with bruxism. Teeth grinding causes friction that deteriorates the surface of materials like porcelain. Porcelain-fused-to-metal or metallic crowns are more suitable options for such situations.
- Porcelain Fused-to-Metal
A porcelain-fused-to-metal crown strikes a balance between the aesthetics of porcelain and the durability of metal. They are used on some front and back teeth, where the appearance of teeth and strength are equally important. The metal hybrid is more affordable than porcelain crowns.
However, porcelain and metal hybrids can deteriorate faster than metal crowns. Another disadvantage is the dark-grey line that shows around the gum line.
- Metal and Gold Crowns
Metal crowns are alloys cast with a mixture of gold and other metals such as copper, nickel, and zinc. Gold is soft and malleable, and therefore, does not provide the durability required by a crown. Metals like platinum are used to increase the strength of the restorative cap.
The strength of the metal crowns varies depending on the amount of gold it contains. Typically, the durability of the alloy ranges in scale from soft to very hard or Type I to IV, respectively.
The advantage of metal crowns is their strength. Their durability makes them suitable for teeth susceptible to damage. For example, a dentist could prescribe a Type IV metal crown for patients with bruxism.
The main downside to metallic devices is their appearance. They are not the best option when the aesthetics of the teeth is the primary concern. Metal is conspicuous, and therefore, suitable for the back teeth.
- Zirconia Dental Crowns
Zirconia is a very hard ceramic material, cast from the chemical element Zirconium. Zirconia crowns can withstand high pressure and last more than two decades. It is considered to be the most durable material used for crowns today.
Zirconia crowns are biocompatible and less likely to cause allergic reactions. They have the aesthetics of porcelain, but the ceramic material is stronger than metal.
The strength of the material can also be a disadvantage. The hard ceramic could wear down the surface of the surrounding teeth. The crown is also challenging to modify once it has been cast.
- Temporary Crowns
Temporary crowns are dental caps worn for a short time as you await the final, permanent crowns. They are molded from resin materials, which are not durable but suitable for short-term protection.
Temporary crowns protect the pulp and dentin after tooth extraction or root canal. They also restore the function of the teeth and gums.
Temporary caps give you the opportunity to evaluate the aesthetics, as you wait to have the permanent crown.
What Are Onlays and 3/4 Crowns?
Onlays, inlays, and 3/4 crowns are variations of the dental cap providing partial cover where a full crown is not necessary. They are best suited for patients with tooth fractures, but where the structure of the tooth is still intact. Onlays and inlays cover the surface of the posterior teeth. They provide protection when a filling would not be sufficient, but where a crown is not the ideal solution.
What is the difference between Onlays, Inlays & 3/4 Crowns?
The difference between inlay, onlays, and 3/4 crowns is the area of the tooth that they cover. Inlays protect cusps on the tooth’s biting surface. Onlays cover multiple cusps and provide more extensive protection for the molars. A 3/4 crown is a hybrid between onlays and full dental crowns. The name comes from the approximate protection they provide for your teeth. While crowns cover the entire tooth, 3/4 fitting protects most of the tooth, about 75% of its surface.
A dentist may remove decayed parts of the tooth before fitting a 3/4 crown or onlay. The tooth is shaped before fitting the crown. A temporary crown may be used to protect the tooth as you await the permanent onlay from the lab.
You will be asked to bite on a mold to take impressions of your teeth. The inlay or partial cap is fabricated using CAD (Computer Aided Design) tools and techniques. One advantage of partial crowns over full crowns is that the former requires little preparation. The dentist only needs to remove a portion of the enamel to fit the cap. However, 3/4 crowns are not ideal for applications where the tooth’s aesthetics is crucial. The metal included in 3/4 fittings and onlays can make the crown conspicuous.
Dental Crowns Procedure: Multi-Day Procedure & Same Day Procedure
Your dentist may complete the procedure in one or multiple appointments. The process will depend on several factors such as the materials used for the crown. Both same-day and multi-day procedures share some similar steps including:
- Oral Health Evaluation:A dentist will examine your teeth and gums for signs of decay or periodontal disease. X-ray images are taken to determine the precise position and orientation of the tooth and the jawbone.
- Local Anesthesia or Sedation: Dentists use local anesthesia when fitting dental crowns. After administering a numbing agent, you will be awake but relaxed throughout the procedure. General anesthesia is sometimes necessary when the patient has severe anxiety or dental phobia. Dental specialists will determine the best option during the initial assessment.
- Tooth Preparation: The next step involves removing or shaping the enamel. A dentist will use various tools to make the surface smoother for better fitting. Some parts of the tooth may require additional support to strengthen the tooth. Improper preparation may cause tooth misalignments and bite problems.
Same-Day Procedure
Same-day crowns only require one appointment to complete the procedure. The dental practice must perform an X-ray, 3D imaging, and tooth preparation on the same appointment. Therefore, special methodologies and materials are needed for a successful process.
- Digital Scan:One-day procedures utilize a digital scan to create an impression of your teeth’s structure. The process is much faster than the traditional mold, which may take weeks to fabricate. Digital scanning produces a more precise model of your oral cavity.
- CAM/CAM Modelling:Computer-Aided Design and Computer-Aided Manufacturing are used to create the crown. The fabrication equipment and applications require special materials to speed up the process. A common material for same-day crown procedures is the CEREC system which stands for Chairside Economic Restoration of Esthetic Ceramic. In this dental technology, the fabrication tools shape the ceramic materials with very high levels of accuracy. This way, the crown fits precisely over your tooth’s enamel.
- Placement:When the crown is ready for placement, a dentist will place it over the shaped tooth.
Multi-Day Crown Procedure
The multi-day procedure could be more convenient for some patients. It is less expensive than same-day procedures. A dentist may provide valuable insights to help you make the right decision. Additional steps for multi-day procedures include:
- Crown Fabrication:A specialist will use the Impressions of your teeth to create a crown that fits accurately over your tooth’s enamel. The fabrication of the crown can take approximately two weeks to complete.
- Temporary Crown Installation:A temporary crown is placed to protect the exposed tooth. It is made of a resin material that breaks down much faster than ceramic. You’ll keep them on until your permanent crown is ready for placement.
- Placement of the Permanent Crown:A dentist will fit the permanent crown on the second appointment. The dental specialist removes the temporary cap and attaches the permanent one with an appropriate dental adhesive. The resin chosen must match the material to ensure the crown can withstand bite and jaw pressure.
Benefits of Dental Crowns
Fitting a crown can be beneficial in several different ways.
- Prevents Tooth Decay & Gum Disease.
The cap fills gaps and eliminates misalignment, making dental hygiene easier. Spaces between teeth can host cavity-causing bacteria which consume the bits of food on the enamel. That way, the crown prevents tooth decay and gum disease. - Reduces the Risk of Breaking the Tooth.
The cap extends over the surface, to minimize damage from internal and external pressures. It holds together a cracked or fractured enamel and reduces the risk of breaking the tooth. An exposed interior of the tooth is more susceptible to infections and decay. - Provides Comfort, Eliminate Soreness & Tooth Sensitivity.
Another advantage of fitting a crown over cracked teeth is comfort. It covers fractures, eliminating soreness and tooth sensitivity. Dental crowns restore the function of your teeth, allowing you to comfortably enjoy your favorite foods after recovery. - Addresses Discoloration and Eliminates Aesthetic Inconsistencies
A crown is also designed to mimic the color and shape of your teeth. The fabrication process is tailored to match the contours of your oral cavity. They not only address discoloration but crowns also eliminate aesthetic inconsistencies like cracks and chips. Crowns will restore your teeth’s appearance and boost your self-esteem.
Cons, Risk, Complications: What Issues Can You Experience Over Time With Dental Crown?
Like all medical procedures, fitting a crown may cause several side effects or complications. The most common side effect is tooth sensitivity after your appointment. You may feel a dull ache or soreness around your teeth, but the discomfort should reduce after a few days. However, sharp pain after the procedure could be a sign of complications. If the pain does not subside, your dentist may recommend an examination to determine if there is a problem. An x-ray will establish if there are anomalies with the placement of the dental cap.
The porcelain surface may also become damaged during the recovery period. Some materials like resin are more susceptible to breaking under high-bite pressure. It is possible to fix minor damage using adhesive, cement, and composite materials. But severe fractures will require a complete reconstruction of the crown.
Gingivitis or gum recession can complicate the healing process. When the gum tissue recedes from the crown, it makes the tooth unstable. A loose tooth will weaken the dental adhesive sealing the boundary between your teeth and gums. It will create an opening for microorganisms, which deteriorate the enamel’s surface making the tooth weaker.
Some patients have an allergic reaction to certain metals like nickel. Allergies may cause discomfort, burning, and itchiness. Lesions, ulcers, and mouth dryness are other possible symptoms of an allergic reaction.
Gingivitis and gum recession may also alter the tooth’s aesthetics. A dark line appears between the tooth and the gum line as the dental cement breaks down.
Dental Implants Aftercare Instructions
Upon completing the crown placement, a dentist will provide aftercare tips and guidelines that foster fast recovery and ensure you protect your restorations.
- Avoid Hard and Crunchy Foods:The bite pressure can chip or fracture your new crown. Adjust your diet to include soft foods. Avoid chewing on the crown side of your mouth, especially on the first few days after your dental appointment.
- Tooth Sensitivity:If there is discomfort when eating hot or cold foods, your dentist can provide toothpaste designed for tooth sensitivity. The discomfort should subside after the first week. If the sensitivity persists, inform your dentist.
- Oral hygiene:Maintain your dental hygiene routine and use a soft bristle brush to avoid damaging the dental adhesive. Dental hygiene also reduces the risk of complications such as gum recession and loose teeth.
- Follow-up Appointments:Scheduled follow-up visits help check the progress of your recovery. Keep your appointments and inform the dentist when you experience discomfort or side effects.
How Long Do Dental Crowns Last?
The durability of crowns depends on the material and the accuracy of the placement. They last between five and 15 years, however, even with the same materials, the crown may deteriorate much faster in some patients. Bruxism or teeth grinding could cause the surface to chip or break. Poor dental hygiene and improper placement are other factors that shorten the lifespan of the crown.
What Are Alternatives to Dental Crown?
Inlays and onlays are the closest alternatives to a full crown. They partially cover the tooth’s surface and are less invasive. Veneers are other alternatives to crowns. A thin shell is placed over the tooth’s surface to conceal chips, fractures, and gaps. They also complement the color of the teeth to address discoloration. However, veneers are mostly used for aesthetic purposes. Even though they can cover spaces between teeth, they do not offer the same protection as crowns.