What Types of Fillings Are There And What Are They Made Of?

In very general terms there are four kinds of fillings: silver amalgam (grey color), gold (gold color), composite resin (white) and ceramic (white).  Silver amalgam when set is a solid metal mixture of primarily silver, mercury, copper, and tin. Gold fillings are a solid metal mixture of primarily gold and small amounts of silver, copper and palladium.  Composite resin is a mixture of an organic resin with an inorganic filler of quartz or glass. Ceramic fillings are composed of ceramics.

Frequently Asked Questions

The scientific answer to this question is all fillings are biologically safe.  However, the media and some people including some dentists say that silver amalgam fillings are not safe and ‘mercury’ fillings will cause lots of problems, which is absolutely not true.  Mercury when it is in a filling is attached to the other metals and can not come out of the filling. Silver fillings do not cause any disease and removal of these fillings will not cure any condition.  Dentists who advise patients to have silver fillings removed are providing incorrect advice that is likely to result in greater tooth problems and certainly much greater cost.

Gold, alloyed with some other metals, has always been considered to be an ideal material as it does not deteriorate over time and does not readily react with other materials.  Pure gold can’t be used as it is too soft. Gold is very expensive and requires great skill to use properly so is not commonly used for fillings.

Composite resin fillings are considered to be safe although they contain materials which have the potential to cause adverse health effects and they slowly break down on the surface.  No side effects have been observed.

Ceramic fillings are considered safe although they are typically attached to the tooth with a layer of composite resin which will slowly deteriorate at the surface.

Silver amalgam and composite fillings are completed in a single appointment although the composite fillings generally take more time.  Gold and ceramic fillings usually require two appointments as the fillings must be made on a mold of your tooth in a dental laboratory after the first appointment and attached to the tooth on the second appointment.

Silver amalgam is the least expensive.  Composite resin is about 1.5 times more expensive than silver amalgam.  Gold and ceramic are about 3-5 times more expensive than silver amalgam.

This will depend on which tooth is filled, the filling size and location on the tooth.  It also depends on the patient’s goals such as appearance, how long the filling is desired to last, how well the filling should work and of course, cost.

In general, for small to moderate sized fillings in front teeth and some small fillings in back teeth, composite resin is a good choice.  Large fillings in front teeth may be temporarily filled with composite resin but generally require a crown.

In general, all back teeth are best filled with silver amalgam.  Small fillings in back teeth could be filled with composite resin depending on the patient’s color preference and budget.

Large fillings or multiple smaller fillings made of silver amalgam or composite resin on the same tooth usually weaken the tooth and a crown should be used to strengthen the tooth.  Large fillings could be made using gold or ceramic and may not need a crown.

Fillings that are on root surfaces, near or covered with gum generally need to be silver amalgam to obtain a lasting seal.

Unfortunately, composite resin is frequently used for moderate to large fillings in back teeth.  Too often, there are problems with poor fit of the filling against the adjacent teeth resulting in food impaction and tooth movement.  In addition, leakage between the filling and tooth causes sensitivity and decay.  Also, difficulty making a proper biting surface results in subsequent wear and tooth movement.  The movement of back teeth will result in the front teeth moving and becoming more crooked.

This will depend on which tooth is filled, the filling size and location on the tooth.  However, if fillings are done extremely well, in our experience they last a minimum of 10 years and often 20 or even 30 years.  Medium to large composite resin fillings in back teeth seem to have some problems often the day they are done.  The problems seem only to get worse although the filling rarely falls out and it still looks nice and white.  Teeth with multiple or large fillings usually should have a crown to prevent the tooth fracturing for which there is no warning, so the crown should not be delayed.

Gold fillings can last as long as the tooth.  Ceramic fillings depend a great deal on how well they are done but are still susceptible to leakage and decay at the margin due to the resin used to attach them.  There is less experience to have long term confidence in them.

No filling will last more than a few months if the teeth are not cleaned well daily.