What is a Composite resin (white filling)?

A composite resin is a tooth-colored plastic mixture filled with glass (silicon dioxide). Introduced in the 1960s, dental composites were confined to the front teeth because they were not strong enough to withstand the pressure and wear generated by the back teeth. Since then, composites have been significantly improved and can be successfully placed in the back teeth as well. Composites -are not only used for restoring decay, but are also used for cosmetic improvements of the smile by changing the color of the teeth or reshaping disfigured teeth.

How is a composite placed?

First all decay is removed and the tooth is further prepared with some roughening so that it can be solidly bonded to. The next step usually involves placing some type of barrier to ensure the area can stay dry, does not get contaminated with saliva or blood, and that only the tooth we want to work on gets bonded to.

Once the tooth is ready, an etch is placed on the tooth to open pores that will allow a mechanical/chemical bond to form. Next a desensitizing agent is placed on the tooth and dried. This is followed by a primer and then a bonding agent that is cured with a special blue light. Finally the composite will be placed in layers, using the specialized light to harden each layer. When the process is finished, we will shape the composite to fit the tooth. We then polish the composite to prevent staining and early wear.

What are the advantages of composite?

Esthetics are the main advantage, since we can blend shades to create a color nearly identical to that of the actual tooth. We can also repair composites without having to replace the entire filling. Also since composites bond to the tooth they can help support the remaining tooth structure. This can be important long term to help prevent cracks leading to breakage of the tooth.