What is a Composite Dental Filling?

What is a Composite Dental Filling?

When the dentist finds a cavity and recommends a filling, the patient will probably have some questions. What will the filling look like? How much will it cost? The answer to these questions depends on the type of material used in the filling, and for that there are a few options. 

Amalgam fillings, which are made of silver-colored metal, have been used to successfully repair teeth for over 100 years. These days, however, the most popular type of filling among dentists and patients is the tooth-colored composite. Designed to match the patient’s tooth color, dental composites can restore teeth without affecting the look of the patient’s smile. Composites cost more than traditional silver fillings and are slightly less durable—but patients and dentists still prefer them for their ability to blend seamlessly with the color of the affected tooth. And the good news is that most dental insurance plans cover composite fillings

Dental Composites

Dental composites are made of resin, which is a hard, synthetic polymer. The resin is mixed with glass or quartz particles to create a hard, tooth-colored dental restoration. Composite material is available in several shades of white, allowing the dentist to make a perfect match to the patient’s tooth. Composite fillings are appropriate for most areas of the mouth, even on front teeth, where appearance is most important. 

Because composites bond directly to the tooth, dentists often need to remove less of the tooth when preparing it for filling. For this reason, composite fillings are often smaller than amalgams. 

Getting a Composite Filling

Once the dentist and patient have agreed on a treatment plan, what is it like to get a composite filling? Like any cavity treatment, a composite filling starts with removal of the tooth decay. Unless the cavity is very small, the dentist starts by numbing the area of the patient’s mouth with a local anesthetic. This prevents discomfort during the procedure. Then using a small drill, they painlessly remove the decay from the tooth. 

Next, the dentist dries the area and applies an etching agent to thoroughly clean and roughen the area to prepare it for bonding. Now it’s time to use composite material to restore the tooth. 

dentist showing patient the new composite filling
Image by Canva.com


Using special techniques and products, the dentist places the composite into the drilled tooth in layers. They shape each layer, then use a blue, ultraviolet curing light on the tooth. The light hardens the filling in place and bonds it to the tooth. Placing the material in layers helps ensure the entire filling is cured and hardened, and it enables the dentist to mold the composite to match the natural shape of the tooth. 

After placing the composite filling, the dentist will check the patient’s bite to ensure that the filling is not too high and that the bite is natural. They may file down rough patches or spots that stick out. 

The filling process is fairly quick and typically takes less than an hour. The patient’s mouth may be numb for a few hours after the procedure. The dentist will provide instructions about when it is safe to resume eating. 

Pros and Cons of Composite Fillings

There are many reasons composites have become the most popular type of filling, the most obvious of which is appearance. Composite fillings match the patient’s tooth in color, can be molded in a natural shape, and are practically impossible to notice. 

Advantages of composite fillings include: 

  • Closely match tooth color and shape
  • May require less tooth to be removed compared to other types of fillings
  • Bond to the tooth and harden in seconds; less likely to fall out 
  • Can be repaired if damaged

Disadvantages of composites compared to other options include: 

  • More expensive than amalgam (metal) fillings 
  • Can become stained over time by coffee, wine, etc. 
  • Wear out sooner than metal fillings 
  • Placement may take longer (and require more skill) than metal fillings 

Types of Dental Fillings

Though composite resin fillings are very popular, patients and dentists have several choices when it comes to filling materials. These differ in appearance and cost. It’s also important to consider how long different types of fillings will last before needing to be repaired or replaced.

Amalgam fillings are a combination of different metals including silver, tin, copper, and mercury. They are highly durable and the least expensive option, but their silver color makes them very noticeable. To get amalgams to remain in place, the dentist may need to remove more of the tooth during the filling process. Although amalgam fillings have been proven to be completely safe, the fact that they contain mercury concerns some patients enough to choose another material. 

dentist placing a composite filling in a patient
Image by Canva.com

Another metal option is the gold filling. Gold fillings are also noticeable. The most expensive filling option, they also last the longest. 

Porcelain or ceramic fillings, like composite, match the patient’s tooth color perfectly. Porcelain restorations are more durable and are less likely to stain than composite. They’re also more expensive. 

Type of Dental FillingAppearance Cost Lifespan
Amalgam (silver)Silver color is very noticeable Least expensive option10-15 years
Composite Matches patient’s tooth color More expensive than amalgams5-10 years 
Gold Gold color is very noticeable Most expensive option 15-30 years 
Porcelain (ceramic)Matches color of teeth; more durable than compositeSimilar in price to gold filings5-10 years 

Beyond Fillings: Composite Tooth Restoration

Composite material is quite versatile and is useful for dental restorations beyond everyday fillings. For instance, composite is a good option to fill in chips or repair broken teeth. It can also restore teeth damaged by teeth grinding (called bruxism).

The material is also used in crowns and veneers. Many dentists use composite in dental inlays, which are dental restorations fabricated and hardened before placement in the patient’s tooth. Dental inlays are appropriate for very large cavities or for replacing existing amalgam fillings. They are an alternative to traditional composite fillings in these circumstances.  

Need a Filling? Find a Dentist Now

Whether you need a filling or another type of dental restoration, composite is an aesthetically pleasing, durable choice. However, the best way to choose a treatment path is in consultation with your dentist. They will help you decide if composite is the best option for your situation. Need help finding a local dental practice? Try our appointment finder