Amalgam Fillings

Used by dentists for more than a century, dental amalgam is the most thoroughly researched and tested restorative material among all those in use. It is durable, easy to use, highly resistant to wear and relatively inexpensive in comparison to other materials. For those reasons, it remains a valued treatment option for dentists and their patients.

Dental amalgam is a stable alloy made by combining elemental mercury, silver, tin, copper and possibly other metallic elements. Although dental amalgam continues to be a safe, commonly used restorative material, some concern has been raised because of its mercury content. However, the mercury in amalgam combines with other metals to render it stable and safe for use in filling teeth.

While questions have arisen about the safety of dental amalgam relating to its mercury content, the major U.S. and international scientific and health bodies, including the National Institutes of Health, the U.S. Public Health Service, the Centers for Disease Control and Prevention, the Food and Drug Administration and the World Health Organization, among others have been satisfied that dental amalgam is a safe, reliable and effective restorative material.

Because amalgam fillings can withstand very high chewing loads, they are particularly useful for restoring molars in the back of the mouth where chewing load is greatest. They are also useful in areas where a cavity preparation is difficult to keep dry during the filling replacement, such as in deep fillings below the gum line. Amalgam fillings, like other filling materials, are considered biocompatible—they are well tolerated by patients with only rare occurrences of allergic response.

Composite Fillings

Composite fillings are a mixture of glass or quartz filler in a resin medium that produces a tooth-colored filling. They are sometimes referred to as composites or filled resins. Composite fillings provide good durability and resistance to fracture in small-to-mid size restorations that need to withstand moderate chewing pressure. Less tooth structure is removed when the dentist prepares the tooth, and this may result in a smaller filling than that of an amalgam. Composites can also be "bonded" or adhesively held in a cavity, often allowing the dentist to make a more conservative repair to the tooth.

The cost is moderate and depends on the size of the filling and the technique used by the dentist to place it in the prepared tooth. It generally takes longer to place a composite filling than what is required for an amalgam filling. Composite fillings require a cavity that can be kept clean and dry during filling and they are subject to stain and discoloration over time.(ADA)

Sometimes the best dental treatment for a tooth is to use a restoration that is made in a laboratory from a mold. These custom-made restorations, which require two or more visits, can be a crown, an inlay or an onlay. A crown covers the entire chewing surface and sides of the tooth. An inlay is smaller and fits within the contours of the tooth.

All-Porcelain (Ceramic) Dental Materials

All-porcelain (ceramic) dental materials include porcelain, ceramic or glasslike fillings and crowns. They are used as inlays, onlays, crowns and aesthetic veneers. A veneer is a very thin shell of porcelain that can replace or cover part of the enamel of the tooth. All-porcelain (ceramic) restorations are particularly desirable because their color and translucency mimic natural tooth enamel.

All-porcelain restorations require a minimum of two visits and possibly more. The restorations are prone to fracture when placed under tension or on impact. The strength of this type of restoration depends on an adequate thickness of porcelain and the ability to be bonded to the underlying tooth. They are highly resistant to wear but the porcelain can quickly wear opposing teeth if the porcelain surface becomes rough.(ADA)

Porcelain-fused-to-Metal

Another type of restoration is porcelain-fused-to-metal, which provides strength to a crown or bridge. These restorations are very strong and durable.

The combination of porcelain bonded to a supporting structure of metal creates a stronger restoration than porcelain used alone. More of the existing tooth must be removed to accommodate the restoration. Although they are highly resistant to wear, porcelain restorations can wear opposing natural teeth if the porcelain becomes rough. There may be some initial discomfort to hot and cold. While porcelain-fused-to-metal restorations are highly biocompatible, some patients may show an allergic sensitivity to some types of metals used in the restoration.(ADA)

Gold Alloys

Gold alloys contain gold, copper and other metals that result in a strong, effective filling, crown or a bridge. They are primarily used for inlays, onlays, crowns and fixed bridges. They are highly resistant to corrosion and tarnishing.

Gold alloys exhibit high strength and toughness that resists fracture and wear. This allows the dentist to remove the least amount of healthy tooth structure when preparing the tooth for the restoration. Gold alloys are also gentle to opposing teeth and are well tolerated by patients. However, their metal colors do not look like natural teeth.(ADA)

Base Metal Alloys

Base metal alloys are non-noble metals with a silver appearance. They are used in crowns, fixed bridges and partial dentures. They can be resistant to corrosion and tarnishing. They also have high strength and toughness and are very resistant to fracture and wear.

Some patients may show allergic sensitivity to base metals and there may be some initial discomfort from hot and cold. However, due to their metal color, gold alloys do not look like natural teeth.(ADA)

Indirect Composites

Crowns, inlays and onlays can be made in the laboratory from dental composites. These materials are similar to those used in direct fillings and are tooth colored. One advantage to indirect composites is that they do not excessively wear opposing teeth. Their strength and durability is not as high as porcelain or metal restorations and they are more prone to wear and discoloration.(ADA)

Veneers-

In dentisty, a veneer is a thin layer of restorative material placed over a tooth surface, either to improve the aesthetics of a tooth, or to protect a damaged tooth surface. There are two main types of material used to fabricate a veneer, composite and dental porcelain .