Filling Techniques & Materials

Advances in modern dental materials and techniques increasingly offer new ways to create more pleasing, natural-looking smiles. Researchers are continuing their often decades-long work developing esthetic materials, such as ceramic and plastic compounds that mimic the appearance of natural teeth. As a result, dentists and patients today have several choices when it comes to selecting materials used to repair missing, worn, damaged or decayed teeth.

The advent of these new materials has not eliminated the usefulness of more traditional dental restoratives, which include gold, base metal alloys and dental amalgam. The strength and durability of traditional dental materials continue to make them useful for situations where restored teeth must withstand extreme forces that result from chewing, such as in the back of the mouth.

What’s Right for Me?

Several factors influence the performance, durability, longevity and expense of dental restorations. These factors include: the components used in the filling material; where and how the filling is placed; the chewing load that the tooth will have to bear; and the length and number of visits needed to prepare and adjust the restored tooth.

With so many choices, how do you know what’s right for you? To help you better understand what’s available, let’s look at the advantages and disadvantages of commonly used dental restorations.

The ultimate decision about what to use is best determined by the patient in consultation with the dentist. Before your treatment begins, discuss the options with your dentist.

Types of Dental Restorations

There are two types of dental restorations: direct and indirect.

Direct restorations are fillings placed immediately into a prepared cavity in a single visit. They include dental amalgam, glass ionomers, resin ionomers and some composite (resin) fillings. The dentist prepares the tooth, places the filling and adjusts it during one appointment.

Indirect restorations generally require two or more visits. They include inlays, onlays, veneers, crowns and bridges fabricated with gold, base metal alloys, ceramics or composites. During the first visit, the dentist prepares the tooth and makes an impression of the area to be restored. The impression is sent to a dental laboratory, which creates the dental restoration. At the next appointment, the dentist cements the restoration into the prepared cavity and adjusts it as needed.

Direct Restorative Dental Materials – One Visit

Amalgam Fillings

Used for well over 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.

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.

Amalgam fillings, like other filling materials, are considered biocompatible—they are well tolerated by patients with only rare occurrences of allergic response.

Disadvantages of amalgam include possible short-term sensitivity to hot and cold temperatures after the filling is placed. The silver-colored filling is not as esthetically pleasing as one that is tooth-colored, especially when the restored tooth is near the front of the mouth, visible when the patients laughs or speaks. And lastly, to prepare the tooth, the dentist may need to remove more tooth structure to accommodate an amalgam filling than for other types of direct fillings.

Composite Fillings

Composite fillings are a mixture of acrylic resin and finely ground glasslike particles that produce a tooth-colored restoration. 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 are "bonded" or adhesively held in a cavity, often allowing the dentist to make a more conservative repair to the tooth.

In teeth where chewing loads are high, composite fillings are moderately resistant to wear, but less so than amalgam fillings. 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. The time required to place a composite filling is usually longer 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.

Composite restorations are more expensive than amalgam fillings.

American Dental Association

Copyright 2002