|SECTION III||DENTAL MATERIALS USED TO RESTORE TEETH|
Pits and fissures that appear caries prone can be treated with dental sealants before the caries process has begun and without any surgical or cutting procedures. When it is deemed necessary to use surgical techniques to restore small carious defects, conservative tooth preparations are most often filled with dental amalgam or esthetic restorative materials like composite resin, glass ionomer, or resin-modified glass ionomer. The materials of choice for restoring larger defects that require protection of thin remaining tooth structure include cast gold or semiprecious or nonprecious metals, porcelain, and more recently zirconia.
Dental amalgam has been a widely used restorative material for well over a century owing to its ease of placement and relatively low cost. It is silver in color and is condensed (packed) into a preparation in successive, small increments that becomes hard enough within several hours to withstand chewing forces. Therefore, amalgam is often used for restorations on the occlusal surfaces of posterior teeth and for restoring posterior proximal surfaces when esthetics is not a factor (Fig. 10-5).
Esthetic restorative materials such as composite resin, glass ionomer, and resin-modified glass ionomer are being increasingly used due to patients’ demands for esthetic restorations. Composite resin is a tooth-colored restorative material. When it is applied directly into a preparation, it has a dough-like consistency and it hardens quickly when exposed to a light source. Historically, in the 1980s, due to initial concerns about the strength and abrasion resistance of composite resins,5,6 it was used primarily for restoring the proximal surfaces of anterior teeth and the facial surfaces of teeth on which esthetics was a chief concern (Fig. 10-6A). Newer generations of esthetic restorative materials developed in the 1990s and 2000s perform well in posterior areas, so composite is steadily replacing amalgam as the restoration of choice for many small class I and II lesions (Fig. 10-6B).9,10