How Dentists Fill A Cavity, Part 2, by Justin K. Hillock, D.D.S.
March 18, 2011 § Leave a comment
In the first part of my discussion, I described how dentists identify cavities and some of the choices available for drilling out the decayed part of the tooth. In this second installment, we will take a look at the filling materials available for teeth. Patients today have several choices for filling materials, each with their own advantages and disadvantages.
One of the most cost-effective filling choices is silver amalgam. Lasting at least 10 years, silver fillings do not need to be replaced very often, and they have the strength to withstand regular chewing. Silver amalgam also costs much less than other filling choices, so it is an affordable option.
Silver isn’t the best choice for everyone, however. For one thing, many people do not like the way silver fillings look in their mouths. On a structural level, silver fillings also cause some complications. A fairly large area of tooth needs to be removed in order to insert a silver filling, which may mean destroying some healthy tooth material. In addition, silver reacts to hot and cold differently than your teeth. As the materials expand and contract at different rates, the filling may eventually put stress on the tooth and cause cracks.
For patients who prefer metal fillings but don’t want silver, gold amalgam may be a better choice. Gold lasts as long as silver and is strong enough for regular chewing. That said, gold fillings cost up to 10 times more than other options, and they require multiple visits to be installed. In addition, if gold fillings are placed too closely to silver fillings, they will create an electric current, called galvanic shock, which can be painful.
Many patients choose composite resin fillings, which are made of glass, plastic, and ceramics. These fillings can be custom-shaded to match the patient’s natural tooth color, and the material is designed to bond well to teeth, making it less likely to come out accidentally. This bonding quality also allows the dentist to drill a smaller hole, saving more of the natural tooth.
Unfortunately, composite resin fillings wear out more quickly than metal amalgam fillings, usually after about five years. They also usually cost more than silver amalgam fillings, and they chip much more easily.
The choice of filling material should be discussed with your dentist before undergoing the procedure. Clearly, there are advantages and disadvantages to all materials, and you should choose the type that fits your needs and lifestyle.
Justin K. Hillock, D.D.S., practices at Coon Rapids Family Dentistry and Guthrie Center Family Dentistry, both in Iowa. He is a graduate of the University of Iowa College of Dentistry.