Dental Amalgam Fillings, Dental Composites, Differences, Pros and Cons

Difference between dental amalgam and composites

Dental amalgam fillings and dental composites are widely used dental restorative materials. Dental amalgam is an alloy of mercury combined with metals such as silver, copper and zinc. It is used as the dental restorative material of choice for over a century in dentistry. It is one of most cost effective, durable and long lasting restorative material available. The major disadvantage of dental amalgam is the metallic color of restoration that causes cosmetic problems if it is used in the front teeth

Dental composites are restorative materials that are derived from combination of two or more chemically different material with a distinct interphase in between. The major advantage with the use of dental composite restorations is availability of various shades and hues to match the exact tooth color and reestablish the aesthetics. It is also a strong and long standing restorative material with minimum side effects.

When to use dental amalgam?

Indications for dental amalgam restorations

Picture of dental amalgam (fillings) from FDA.gov

• Moderate carious lesions (tooth decay) present on the grinding surface of molars and premolars.
• Carious lesions (tooth decay) present over the interdental area of the teeth.
• Grossly destroyed posterior (back) teeth.
• When the cusp of the tooth is to be replaced.
• As a foundation for cast gold restorative procedures.
• As a part of endodontic therapy.
• In teeth with questionable dental pulp health, amalgam is indicated as an interim solution before placing a definite restoration.
• Amalgam restorations are to be considered when cost of the restoration is a major factor for the patient since it is cheaper than composites.

When to use dental composites?

Indications for dental composite resin restorations

Dental composite picture from University of Missouri Kansas City

• Composite resins are indicated for deep grooves, pits and fissures present over the grinding surfaces of the molars.
• Most of the cases of decay on the front teeth are treated with composites due to the aesthetics and stability of the restorative material.
• Any restoration of incisors such as enamel or dentin fractures can be restored using dental composites.
• Composites can also be used as a core building material for other restorative procedures.
• Dental composites are often used as a luting agent for various cavities and as an interim restoration.
• In orthodontic procedures, composite resins can be used for attachment of fixed mechanotherapy and orthodontic appliances.
• Aesthetic corrections of dental problems such as spacing, midline diastema and smaller sized teeth (microdontia) can be treated using dental composite restorative materials.
• The other indications for dental composites include periodontal splinting of weakened or mobile teeth, repair of fractured ceramic crowns and indirect restorations.

Which dental restoration material should be used?

Deciding between dental amalgam fillings and dental composites

Both the restorations have their advantages and disadvantages. It is necessary for the dentist to first diagnose the lesion appropriately and consider all factors such as aesthetics, longevity, condition of tooth, dental pulp and periodontium, oral hygiene of the patient’s habits and financial position. The choice of restoration should be such that it should yield maximum benefit to the patient and serve for a long duration.

The main advantages of restoring a tooth in early stages include preventing the spread of dental caries by reaching the dental pulp. Tooth decay is caused by bacteria. If these bacteria reach the pulp and cause pulp necrosis the tooth is destroyed. An existing lesion of tooth decay cannot be reversed and needs to be restored using dental restorative material such as dental amalgam fillings or dental composites.

How is dental amalgam and composites inserted?

Procedure for dental amalgam and composite fillings

• The decayed portion of the tooth is removed using a rotary instrument under strict isolation.
• The surface of the tooth is prepared for restoration placement.
• The restorative material is then inserted within the cavity and is allowed to set.
• This is followed by manipulating the restorative material to mimic tooth anatomy by carving the restoration surfaces with dental grooves.
• The restoration is then finished and polished using different methods.

What are the pros of dental amalgam fillings?

Advantages of dental amalgam fillings

• Dental composites restoration requires ideal isolation of the operative field and may not yield good results in lack of complete isolation while dental amalgam can be used in areas where isolation is difficult.
• Dental amalgam can be used in cases with high incidence of cavities and teeth with questionable prognosis, while dental composites are contraindicated in such situations as there is an increased risk of secondary cavities and marginal staining.
• Dental amalgam can be used in patient with parafunctional habits such as bruxism (grinding of teeth) since dental composites cannot withstand heavy occlusal forces during grinding.
• Dental composites are not used in root surface cavities as it may achieve a less than satisfactory marginal seal, while dental amalgam can be used in such cases with good results.
• Dental amalgam is easy to manipulate as compared to dental composite which is highly technique sensitive and requires excellent operative skills.
• Finishing and polishing of dental amalgam is easier as compared to dental composites.
• Dental amalgam is less expensive as compared to dental composites.

What are the pros of dental amalgams?

Advantages of dental composites

• The aesthetics of a composite restoration is excellent when compared to amalgam, as amalgam cannot be used as an anterior restorative material because of the lack of tooth like color.
• While preparing a cavity for dental amalgam restoration, the ideal cavity preparation is necessary to achieve a good seal. In order to achieve the ideal cavity, excess of tooth material is removed during amalgam restoration. On the other hand dental composites require minimum tooth preparation and no mechanical retentive features.
• Amalgam, being a metal is thermally conductive and can lead to galvanisms inside the oral cavity if used along with gold or other metallic restorations. Dental composite resins have low thermal conductivity and therefore provide insulation to the underlying dental pulp.
• Dental composites provide a better attachment to the tooth surface by micromechanical bonding as compared to the dental amalgam
• Dental composites have advantage in the manipulation stage of the restoration as the material sets after light curing, while dental amalgam has a fixed setting time and all procedures should be carried out before the material sets.
• Dental composite restorations can be repaired rather than replaced unlike with amalgam fillings.
• A wide variety of dental composites are available in market with excellent color and application type variations.

Dr. Geraldine Golder

She is one of the best dentist in town, known for her exceptional skills in oral care and commitment to patient comfort. With a gentle chairside manner and a passion for creating beautiful, healthy smiles, she has become a trusted name in dental healthcare