Dental Filling Material

There are a number of different filling materials that are used in modern dentistry practice.  The fillings are divided into inlay (inside the tooth) and onlay (outside).  Here are the different types of fillings:

Amalgam

This is the most commonly used material for back teeth. It contains approximately half mercury, and differing amounts of silver (30%), tin, zinc, and copper. It is the cheapest and it takes little time to insert.  It does not hold its shape over time and it corrodes easily.  Amalgam filling is expected to last 5-10 years, although some fillings last to up to 20 years.  There used to be a controversy about mercury and its poisonous effects on the human body but there hasn’t been enough evidence to support the claim.

Galloy

This is a brand new material containing silver, tin, copper, indium, and gallium, meant to be mercury-free alternative to amalgam though it is surprising that this material is being developed since amalgam is supposed to be safe.

Direct Composite

The most popular of inlay fillings this is a special plastic material that bonds to tooth structure.  The advantage is that direct composite is tooth colored, is more easily repairable as well as it requires less tooth structure to be removed than with any other material.  It lasts 5 to 7 years although smaller fillings are said to last longer than that. Research has shown that direct composite filling reinforces the tooth and makes it stronger. It is more costly than amalgam and it takes longer to insert this type of filling but overall its advantages make both investments worthy.

Indirect Composite Inlay/Onlay Filling

This is used when ideal anatomy, fit, and durability is desired, which is seldom achieved with a direct composite filling. Cost is approximately two to three times more than amalgam and it takes about two visits.
Porcelain Inlay/ Onlay

This is used when cosmetics and wear resistance is most important for a patients. This type of filling osts about the same as an indirect composite inlay/onlay and takes two visits.

Gold Inlay/Onlay

This type of filling is used when maximum strength is desired and appearance is not much of a concern.  It is costly – three to four times more than amalgam – and it takes two visits.   

Titanium Inlay/Onlay

This issed when a gold alloy is not possible.  Its benefits, cost, and time to perform are the same as for a gold filling despite the fact that titanium is not a precious metal. It takes two visits.