Also called: Restorative Dentistry, Tooth Restoration
Andrew M. Sicklick, D.D.S.
Dental restorations are used to restore damaged or decayed teeth. They can frequently save teeth that would otherwise need to be extracted. Restorations include fillings, inlays and onlays, veneers, crowns, implants, bridges, and dentures. Dental restorations can be described as direct and indirect restorations. Some restorations require multiple visits to the dentist (e.g., crowns, bridges). Restorations can be made from a number of different materials, including amalgam, composite resin, ionomers, metal alloys, porcelain and porcelain fused to metal.
Before the dental restoration procedure begins, patients need to see a dentist for a dental examination to determine what type of restoration is right for them. The dentist may also evaluate the patient’s medical and dental history. The general process for dental restorations is similar for all types of restoration. The tooth is first prepared for the restoration. Any tooth decay is removed and the tooth may be reshaped. If an indirect restoration is to be used, the dentist will take an impression to make the restoration. The restoration can then be placed and adjusted as needed. Once placed, restorations do not usually cause discomfort.
The longevity of a dental restoration depends on many factors, including the patient’s health, dental hygiene, type of restoration, material and the location in the mouth. In general, dental restorations require the same care as natural teeth. However, it is typically recommended that patients with restorations avoid placing unnecessary stress on the restoration. Dental restorations can chip, fracture, break, come loose, fall off or become stained.
About dental restoration
Dental restorations are among the most common dental procedures and include fillings, inlays and onlays, veneers, implants, crowns, bridges, and dentures. They are used to restore damaged, decayed or missing teeth. They can also relieve associated dental pain. They can frequently save teeth that would otherwise need to be extracted. Direct restorations are made in the dental office directly in the patient’s mouth. Indirect restorations are made in a dental laboratory using impressions made of the patient’s teeth. These usually require multiple visits to the dental office. Restorations can be performed on both permanent and primary teeth. Restoration on primary teeth is performed in the same manner as permanent teeth.
Restorations require removing portions of damaged teeth. For some types (e.g., crowns) the teeth will be filed down to accommodate the added material. There is usually little or no discomfort after a dental restoration has been placed, although some patients may experience sensitivity to hot and cold. Restorations can be damaged or dislodged by stresses from chewing on hard substances (e.g., nuts, ice), oral piercing, grinding teeth and biting fingernails.
Modern dental restorations can be made from different materials. The right material for a particular case is typically determined by a dentist in consultation with the patient. The decision is based on factors such as the patient’s dental and overall health, the type of restoration used, and the location of the restoration. Restorations may be cemented or sealed into place. Types of materials used in dental restorations include:
- Amalgam. A mixture of mercury, silver, tin, copper and other metals, this material is used in fillings that require strength (e.g., the molars). Amalgam is easier to place than other materials. It can tolerate some moisture during the placement procedure and is less expensive. It is very strong and highly resistant to wear. Amalgam requires removing a larger amount of tooth structure than composite resin or ionomers and may cause hot or cold sensitivity after it has been placed in some patients. There has been some debate on the safety of amalgam fillings due to their mercury content. However, according to the American Dental Association (ADA), U.S. Centers for Disease Control and Prevention (CDC), National Institutes of Health (NIH) and the U.S. Food and Drug Administration (FDA), there is no sound scientific evidence of a link between amalgam and these or any other health problems.
- Composite resin. A material made of glass or quartz fillers and an acrylic plastic material. It may be used to make fillings, inlays and onlays, veneers, and crowns. The color and translucency closely match natural teeth. Composite resin is resistant to wear and fracture. It is well-tolerated by patients and gentle to nearby teeth. However, it stains more readily than porcelain and is not as strong as porcelain or amalgam materials.
- Ionomers. Materials made of acid and glass powders that contain fluoride. They may also include acrylic resin for additional strength. Ionomers are used for small fillings in areas without much stress (e.g., between the teeth, tooth roots). They may also be used to line cavities and as cement for crowns and bridges. Ionomers release fluoride into the teeth and can help prevent tooth decay. The color closely matches natural teeth and they are well-tolerated by patients. However, ionomers are prone to fracture and can wear down quickly.
- Gold alloys. Composed of a combination of gold, copper and other metals, these are used to make inlays, onlays, crowns and bridges. The materials are tough and highly resistant to tarnishing, corrosion, fracture and wear. They do not usually require as much removal of the underlying tooth as other types. They are gentle to nearby teeth and are well-tolerated by patients. However, patients may not like the metallic gold color.
- Base-metal alloys. Materials made of a combination of base metals (e.g., nickel, chromium). They are used for crowns and bridges. These materials are strong and highly resistant to fracture, wear, tarnishing and corrosion. This type does not usually require as much removal of the underlying tooth. However, they have a metallic silver color that many patients do not like. They may also cause sensitivity or discomfort with hot and cold in some patients.
- Porcelain. Made of porcelain, ceramics or glasslike materials. All-porcelain inlays, onlays, veneers and crowns are available. These materials can closely match natural teeth and are resistant to wear. However, they may be prone to fracture and can wear down nearby teeth if the porcelain surface becomes rough. They require removing a larger amount of natural tooth for a strong crown. Porcelain tends to be more expensive than metal alloys.
- Porcelain fused to metal. Made of a porcelain surface bonded to a metal base. This material is often used in crowns. The combination of porcelain and metal is very strong, durable and highly resistant to wear. The color also closely matches natural teeth. This material can wear down nearby teeth if the porcelain surface becomes rough. It may also cause sensitivity or discomfort with hot and cold in some patients. In addition, this type requires removing a larger amount of natural tooth to support the material.
Researchers are investigating potential new materials for dental restorations that may be stronger, less brittle, more attractive and more like natural teeth than currently available materials.
Types and differences of dental restoration
Dental restorations include direct and indirect restorations. Direct restorations are made in the dental office directly in the patient’s mouth. Indirect restorations are created in a dental laboratory using impressions made of the patient’s teeth. These usually require multiple visits to the dental office. Typically, a temporary restoration is placed in the patient’s mouth between these visits. Indirect restorations tend to be more expensive than direct restorations, even when they are made from similar materials.
Only a dentist can decide what type of dental restoration is right for a particular patient. The different types of restorations include:
- Fillings. These direct restorations are used to repair teeth that have been damaged by tooth decay and cavities. They can be used for the repair of very small or moderately sized areas of decay in primary or permanent teeth. Fillings can be made from amalgam, composite resin, or glass or resin ionomers. The longevity of a filling depends on several factors, such as the material, location, patient circumstances and skill of the dentist placing it.
- Inlays and onlays. These indirect restorations can cover some or all of the chewing surface of molars or premolars. They are larger than fillings, but do not cover as much of the tooth as a crown. Inlays lie entirely within the contours of the tooth, between the cusps. Onlays cover at least one cusp. Both inlays and onlays can restore a tooth too badly damaged for a filling. The choice depends on how much of the tooth needs to be restored. For example, onlays are generally preferred when more than half of the chewing surface needs restoration. Inlays and onlays can be made from gold or other metal alloys, composite resin or porcelain and usually last for decades.
- Veneers. Indirect restorations that are extremely thin shells placed on the front side of teeth. They are primarily used for cosmetic purposes (e.g., stained teeth, chipped teeth, gaps between teeth) and may be crafted from porcelain or composite resin. The lifespan of veneers is similar to crowns but depends on patient maintenance.
- Crowns. These indirect restorations cover the entire visible portion of a tooth. Crowns can restore severely damaged teeth that other restorations cannot. They are also frequently used with bridges and implants. Crowns may be made from gold or other metal alloys, porcelain, porcelain fused to metal or composite resin. Crowns will usually last seven years or longer.
- Implants. An implant is an indirect restoration made of an artificial tooth root that supports an artificial tooth or teeth (e.g., crown, bridge, dentures) surgically placed in the jaw. Implants are used to replace missing or lost teeth with stable, well-anchored, natural-looking artificial teeth. Implants are usually made of titanium metal alloy.
- Dentures. A type of indirect restoration made of a removable dental appliance to replace missing teeth with artificial teeth attached to a gum-like denture base. Preparation and placement requires multiple visits to the dental office. impressions of the mouth and gums are taken and the materials are designed to look like natural teeth. They are usually made of porcelain or acrylic resin.
- Surgical restoration. Teeth and gums damaged by accidental injury or disease may be repaired using different types of restorations depending on the damage. Surgery to repair the initial trauma and to restore and maintain teeth and gums may be necessary.
Before the dental restoration procedure
Before the dental restoration procedure begins, patients need to see a dentist for a dental examination to determine the type of restoration. The dentist may also evaluate the patient’s medical and dental history. Other dental procedures may be necessary before some dental restorations. For example, a root canal treatment may be required before a crown can be placed.
The general process for dental restorations is similar regardless of the type of restoration used. The differences lie in the details that occur with each step. For specific information on each procedure, see the individual patient guides for those procedures.
The tooth first has to be prepared for the restoration. After isolating the site to block moisture and contamination, any tooth decay that is present is cut away from the tooth. The enamel of the tooth generally needs to be filed down and shaped to accommodate the size of the restoration. In some cases, preparation involves air abrasion to repair cracks and prepare tooth surfaces. The amount of removed tooth structure depends on the type of restoration and the material. For example, with veneers, a small amount of enamel needs to be cut away, whereas crowns require extensive reshaping. Anesthesia may be used during this process. Topical or local anesthesia may be all that is necessary.
When necessary, the dentist will take an impression of the prepared teeth and surrounding area. The impression is sent to a dental laboratory to make the restoration. A temporary restoration is commonly used while waiting for the permanent restoration to be made.
During and after dental restoration
If a temporary restoration was used, it is removed and the permanent restoration is tested before it is placed. For example, a veneer will be placed on the teeth with water instead of cement to make sure it fits properly and matches the surrounding teeth.
In many cases, the prepared cavity is lined with a material (e.g., glass ionomers) for protection and insulation and to help bond the restoration to the tooth. It is then molded, cemented or bonded into place. Some restorations may be hardened using a special light or laser.
After placing the restoration, the dentist may need to make some adjustments, such as polishing or grinding. This may occur during the same appointment that the restoration is placed or in subsequent dental visits.
There is usually little or no discomfort after the placement of a dental restoration, although some patients may experience sensitivity to hot and cold.
Risks and benefits of dental restoration
Dental restorations can frequently save teeth that would otherwise need to be extracted. Depending on the material used, they can also closely match the natural appearance of teeth. The longevity of a dental restoration depends on many factors, including the patient’s health and dental hygiene habits, the type of restoration and material used, and the location of the restoration in the mouth and the skill of the dental practitioner.
In general, restorations require the same care as natural teeth. However, it is typically recommended that patients with restorations avoid chewing on hard substances (e.g., nuts, ice), grinding their teeth, biting their fingernails or otherwise putting unnecessary stress on the restoration. It is also important to see a dentist regularly for a dental examination and cleaning.
Restorations may chip, fracture or break. Sometimes they can be repaired without removing the restoration. However, damaged restorations must often be removed and replaced. Certain lifestyle habits, such as oral piercing, can increase the likelihood of a restoration being damaged due to close contact from metal. People with restorations are generally advised to avoid oral piercing.
Restorations may also become loose and unstable. When this happens, tooth decay can form beneath the remaining tooth. It is important to consult a dentist if a restoration becomes loose. It can often be re-cemented before any damage to the tooth occurs. New cements and sealants are available that may help to prevent decay from developing beneath restorations. If the tooth is damaged, the restoration will no longer fit properly and a new one will be required.
Occasionally, a restoration may fall out entirely. If a restoration is lost, it is important to consult a dentist as soon as possible to ensure that the remaining tooth is not damaged.
Changes in the material of a restoration (e.g., stains, wear) or changes in the surrounding teeth (e.g., whitening attempts) may cause a restoration to become unattractive. When this occurs, patients may wish to have the restorations replaced.
Questions for your doctor on dental restoration
Preparing questions in advance can help patients to have more meaningful discussions regarding their conditions. Patients may wish to ask their doctor the following dental restoration-related questions:
- Why do I need dental restoration?
- How many of my teeth need to be restored?
- What type of restoration is right for me?
- Are there multiple possibilities for my restoration? What are the advantages and disadvantages of each?
- Will you complete the entire procedure or do I need other types of dentists as well?
- What materials will be used to make my restoration?
- How closely will these materials match my natural teeth?
- How many appointments will my restoration require?
- Will I need to have a root canal treatment or any other preliminary dental work?
- How much of my natural tooth needs to be removed?
- Do I need to have a professional cleaning before my restoration?