Dental Crowns
What is a Dental Crown?
A crown is a cover or “cap” placed over your tooth. The crown restores the original shape, size and function of the tooth. A crown can make the tooth stronger and improve the way it looks. A dental crown is usually cemented onto the tooth and restores the tooth’s functionality.
What are Crowns Made From?
Crowns are crafted from several types of materials. Ceramics, porcelain metal alloys, porcelain-fused-to-metal, or composite resin can be used. The most popular types of dental crowns are the ones crafted from porcelain, which blend in with your natural teeth. However, the type of dental crown your dentist recommends is dependent on a few factors:
the tooth’s location and function.
the position of the gum tissue.
your preference.
the amount of tooth that shows when you smile.
the color or shade of the tooth.
Why is a Dental Crown Needed?
Protection: dental crowns offer protection to teeth that have weakened due to decay, previous large restoration, or injury that has resulted in damage to the tooth. Dental crowns are also used to hold together the parts of a tooth if it has been fractured or cracked.
Restoration: dental crowns are used to restore a tooth that has been cracked, chipped, broken, or worn down, to its normal functionality.
· Aesthetics: They can be used to conceal or correct misshaped, misaligned, or discolored teeth.
In children, other reasons a dental crown may be indicated include:
Protect any tooth that has been damaged as a result of decay and cannot be restored using a dental filling.
Protect teeth that are prone to decay, possibly due to lack of or poor oral hygiene habits, and to prevent future perhaps more extensive dental appointments.
Different Types of Dental Crowns
1. Stainless Steel: Stainless steel crowns are made from metal and are used to repair a decayed baby molar (back tooth) and also to prevent further decay. Stainless steel crowns are designed to precisely fit a child’s molar and cap teeth with large or deep cavities. They are an alternative to silver and tooth-coloured fillings, and are very durable. Metal crowns can sustain biting and chewing forces and generally last the longest in terms of wear. They have a smooth polished surface which makes them easy to clean.
2. Metal: These types of dental crowns include alloys that have a high content of gold, platinum, or base-metal alloys (i.e. cobalt- chromium and nickel-chromium alloys). Metal can require less tooth preparation and rarely chip or break. The metallic color (typically gold) is the main drawback. Metal crowns can be a good choice for out-of-sight molars.
3. All-resin: These types of dental crowns are typically used in temporary situations (i.e. while you are waiting for your permanent crown to be fabricated) as they wear down over time and are more prone to fractures than other full coverage crowns.
4. Porcelain-fused-to-metal: These dental crowns have metal underlying a porcelain covering. They can be color matched to your adjacent teeth but sometimes the metal underlying the crown’s porcelain can show through as a dark line, especially at the gum line (even more so if your gums recede). Occasionally the crown’s porcelain portion can chip or break off. These crowns can be a good choice for front or back teeth as well as long bridges where the metal is needed for strength.
5. All-porcelain or all-ceramic: These dental crowns provide the most natural color match of all the other crown types and allow for a natural look anywhere in your smile. Today’s improved porcelain choices make them extremely durable as well so they can also be used in circumstances where added strength is required.
How Long Do Dental Crowns Last?
This depends mainly on how well they are maintained through good oral hygiene practices. The risk of porcelain fracture dramatically increases if a patient grinds their teeth, which can significantly minimize the lifespan of the dental crown. Usually a night guard will be recommended in these cases and worn during sleep, to ensure this type of damage does not occur.
What is the Process of Getting a Dental Crown?
Appointment 1: The first visit involves checking the tooth by use of oral examination and x-rays for a deeper look at the affected tooth. This can often be done at your 6 month check up and hygiene appointment.
Appointment 2: The next appointment will be to prepare the tooth. This involves recontouring the tooth to ensure the dental crown can fit and cover the tooth comfortably.
Following this step, an impression of the prepared tooth is taken and used as a mold for the fabrication of the permanent dental crown. A temporary dental crown will then be placed on the prepared tooth to ensure it is comfortable while the permanent crown is being fabricated in a dental laboratory. At your next appointment, the temporary crown will be removed by your dentist and replaced with the permanent crown.
Appointment 3 (2 weeks later): The temporary crown will be removed and replaced with the permanent crown. Your dentist will check to see if the dental crown fits well and does not require any other adjustments. If all is acceptable, the crown is permanently cemented.