Services - Cosmetic Dentistry: Tooth-Colored Fillings   Introduction to Dental Bonding   Tooth-colored fillings can be chosen to match the color of the teeth, making them a natural-looking alternative to amalgam fillings.   Tooth-colored fillings are often used in teeth that show during smiling or talking. They are not as durable as amalgam, and so they aren't always suitable for the grinding and chewing surfaces of the back teeth.   There are a few different types of tooth-colored filling materials. The most common are called composite and glass ionomer. They are soft and can be molded to look like the shape of a tooth before they are hardened, usually using a blue light. Tooth-colored filling materials stick to teeth, so they can be used to build up the edges of chipped or worn teeth.   Composite shrinks very slightly under the blue light. This can pull on the tooth and may cause sensitivity. It can also produce a tiny gap between the filling and the tooth that may lead to further decay.   Tooth-colored fillings must be kept completely dry until they have set, so the dentist will take special precautions to keep saliva away from the area. This may include placing a sheet of rubber over the tooth (called a rubber dam).   Bisphenol A Tooth-coloured filling materials do not contain mercury. However, there have been concerns that they release a chemical called bisphenol A. This chemical is also used in the manufacture of some food packaging and water pipes.   Bisphenol A appears to mimic the action of human oestrogen hormones, and has been linked to breast cancer, prostate cancer and male infertility. The British Dental Association has looked into this, and found that most filling materials do not release bisphenol A, so there is no oestrogenic effect.2 However, this chemical is being used less in newer filling products.     Advantages & Disadvantages of Composite Resin Fillings   Advantages: The composite of composite resin fillings bonds to further support the remaining tooth structure, which helps prevent breakage and damage to your tooth. They certainly look better, and are color blended to match your natural tooth color. These fillings are often used to improve the appearance of misshapen, chipped or discolored teeth.   Composite resin fillings last about six to twelve years or more, and the procedure usually takes just one visit to your dentist. There is very little sensitivity to hot or cold items often experienced with amalgam fillings. The dentist won't need to drill as much of the tooth structure as with amalgam fillings.   Disadvantages: Composite resin fillings require more time to apply than amalgam fillings. This results in an increased cost for placing composite fillings.