A large number of people had amalgam fillings (silver) or gold filling restorations in the past. Some amalgam fillings contained mercury. Metal fillings were effective, but very conspicuous and tended to blacken in color over time. Another disadvantage of metal fillings is that they tend to cause cracks and break the natural teeth over time.
Tooth-colored fillings (white fillings) or composite resin dental fillings were created as an alternative to traditional metal dental fillings.
Composite, tooth-colored fillings are made of a resin filled with microscopic porcelain particles. The strength of current composites is similar to the strength of silver mercury fillings. The advantage of a composite filling is that it is bonded to the tooth. This prevents that natural tooth from breaking and cracking. Research has shown that a well-sealed composite filling can restore the strength of a decayed tooth almost to the level of an unfilled tooth.
A well-sealed composite filling can last as long as a silver mercury filling. A well-sealed composite filling can last as long as a silver mercury filling. While composite restorations can take twice as long to place as silver mercury fillings and are somewhat more costly; they may prevent a tooth from fracturing, saving time and money in the long run.