Tooth fillings

Tooth cavity filling - types, precudere and costsIf you have ever had a cavity and needed to be “drilled“ by the Dentist, then you know exactly what a filling is.

The word “filling” derives from the word “fill” which is the procedure done to the tooth when the cavity or damaged area is drilled out and the space is “filled” with a special substance to keep the strength of the tooth and to keep the look of the tooth.

The techniques have not changed that much, but the equipment and substance used have developed to make the procedure less painful and more permanent.

Let’s go into details about this type of dental treatment. You will get answers to the following questions:

  • Why would I need a filling?
  • Are fillings painful?
  • What types of fillings are available?
  • Should I get fillings if recommended?

Why would I need a filling?

Cavity filling

The number one reason why anyone would require a filling is because of a cavity in their tooth. A cavity is tooth decay and softening of the enamel caused by acids which occur when sugar is broken down into the mouth. The enamel is a very strong natural substance, but once that is weakened, then decay is right around the corner. Not all cavities need a filing, although they must be very small and continually monitored by your dentist.

When the tooth decay starts and is irreversible, the decay must be drilled out to stop the spread and to strengthen the tooth with a filling. The filling will help give the tooth back its shape so that it resembles its previous look and ability to function properly. Later in the article we will discuss the types of fillings used.

Fractured Tooth

Although teeth are extremely strong and hard, they can crack and chip which sometimes requires a filling. The front teeth are prone to being chipped as they are most exposed and shaped much differently than say a molar. Molars on the other hand are built much stronger but bear the brunt of the chewing process, and can be cracked by chewing a hard substance. Sometimes a cracked tooth results in pain or sensitivity if the nerve is exposed, but there are also circumstances when only a check-up from your dentist can discover the problem.

Some cracks or fractures in the tooth can be minor and not require any repair. Those with a larger crack or fracture, need to be treated as soon as possible. Because the enamel is cracked or broken off, the rest of the inner tooth is exposed and susceptible to decay and/or infection. In extreme cases, the tooth will be removed, but in most a root canal with a crown or a filing will be sufficient.

Replace Old Fillings

Old and deteriorating fillings are also a big reason for new fillings. Nothing lasts a lifetime, and fillings which have been there for decades can easily fail from the daily wear and tear. As not all dentists are the same, a small mistake from years past can develop in something more serious. Sometimes they might be detected from pain or visible decay of the filling, although many times the issue is under the old filling and only can be detected through an X-ray.

The old filling is usually drilled out, along with any decay, and replaced with a new filling. In the case of serious infection and/or decay, root canal may be needed. There is still need for a filling during the root canal procedure, but this is usually followed by a crown which covers the filling.

Gradual Loss of Tooth Structure

Teeth are made to last, but as with any part of the body, the daily wear and tear can do serious damage. Damage may occur from your diet, chewing, bite, eating disorders (Bulimia) and of course using your teeth as a Swiss Army Knife (i.e. opening beer bottles). All of this is considered “slow tooth loss” and occurs over time and is not always obvious. The only way to keep this loss in check is through scheduled visits to your dentist.

Slow loss of tooth structure is treated the same as most cavities, cracks and fractures. As always, in extreme cases the tooth may be pulled or need root canal followed by a cap or crown.

Tooth Discoloration

Teeth can get discolored and when they do, the cause must be evaluated. One reason for tooth discoloration is a filling which becomes stained or gradually changes color. Sometimes when there is a large filling, it can make the whole tooth structure a shade off from the other teeth. If it’s a molar, the color might not matter as much, but if it’s in the front, you’ll want to have it remedied.

If the filling becomes stained or discolored, it is not usually the case to have the whole filling drilled out. In many instances, the stain is on the surface of the filling, and with a bit of light drilling and sanding, the stained area can be removed. If the whole structure is discolored, the whole filling might be replaced depending on the issue, or a crown can be placed on the tooth. The fillings themselves can sometimes be stained from the food we eat or what we drink, so be conscious of what you are putting in your mouth.

Are fillings painful?

That depends on your definition of “painful”…… Just kidding! If you need a filling, it means that you are having issues with your tooth, most notably a cavity. To “insert” the filling, the cavity must be drilled out, to prevent further decay. Usually the dentist will inject you with a local anesthetic which will numb the area. Inserting the needle can cause a bit of a “prick”, but once the anesthesia starts working, there will be no pain issues.

No one likes going to the dentist and having a stranger putting their fingers and instruments into their mouth, but getting a filling has become very routine, and with technology as advanced as it is, it’s not painful.

What types of fillings are available?

5 types of fillings are available:

  • Amalgam
  • Composite Resin
  • Cast Gold
  • Ceramics
  • Glass Ionomer

All 5 have their advantages and disadvantages, so be sure to discuss with your dentist which filling is best for you.

Amalgam (Silver)

This substance is a smorgasbord of ingredients consisting of silver, zinc, copper, tin and mercury. Mercury is about 50% of the substance, so many times it is referred to as a “mercury filling” or “silver filling”. This non-bonded substance is usually used for the back teeth and lasts for over 10 years.

The advantages to Amalgam is that it is very cheap compared to the other types of fillings. They are very strong and the most resistant to chewing, which is why they are used mainly in the molars. One trip to the dentist is all you need and these are the most common among the various fillings.

When using Amalgam, the tooth needs a lot more preparation then the other fillings, which requires spending more time at the dentist office. Because of the many substances in Amalgam, the color does not match the tooth and the filling can change color over time.

Mercury has gotten bad press in recent years, although studies and research shows that the amount of Mercury in a filling has no effect on your health. As a matter of fact, the Mercury in your mouth is what you would normally be exposed to in your daily life. It’s been used in so many instances and with so many people throughout the years, that if there was a long-term issue, it would have been discovered now.

Glass Ionomer

This filling is made of a component of glass called fluoroaluminosilicate (catch your breath) and Acrylic. This type of filling is used primarily on the front teeth and is much stronger than the other variety of filings. Because of its strength and resiliency, the compound is also used in baby teeth and the part of the tooth (root caries) which is below the gum line.

Glass Ionomer can last over 5 years and releases fluoride in the tooth and can assist in preventing further decay in that tooth. As a sticky substance, the filling can bond to the tooth much better and create a better seal between the tooth and the filling. The color can come close to matching the tooth but at closer inspection can be detected.

Compared to composite resin, Glass Ionomer is not as strong and cannot match the color as well. Because of the filling layer process, the procedure is more precise which can increase the amount of time to complete.


Usually a porcelain substance, these fillings are at the high end of the spectrum in terms of cost, but can give you the most natural look of all other filling varieties. These can be the solution when a regular filling is just not enough, although a crown would be a bit of overkill. Computer aided design is used in the process, although it’s a somewhat quick procedure and can be finished in about 1 hour.

To prepare the tooth, the tooth must be sculpted to a small size so that the onlay can fit on top of it. Although they look great, they are not as strong and can be a bit brittle, making them susceptible to cracking or breaking.

Cast Gold

As the name implies, these fillings are made with gold or more specific gold alloy (gold mixed with other metals). As we know gold is a very expensive substance, so much so, that the cost of gold fillings can be 10x more expensive than the regular Amalgam (silver) fillings. But with cost comes advantages, such as lasting for over 15 years. The strength of these fillings is second to none and because of the high amount of gold, do not corrode. Gold can be used for inlays, onlays and crowns, which makes it a highly desired dental substance.

Of course, not everyone is comfortable with gold in their mouth, as it can look a bit garish. As a crown, there are some people who wouldn’t want anything else other than gold. Gold fillings require 2 trips to the dentist, once for an impression to be made of the tooth and the second to have the gold placed in or on your tooth. A sometime rare occurrence is “galvanic shock” which is the interaction between a gold filling and silver filling. This can cause some discomfort but is a very rare event.

Should I get fillings if recommended?

YES! If you are concerned with taking care of your overall health, then I would highly recommend getting fillings when needed. The short-term inconvenience will outweigh any long-effects, which will no doubt occur. Reasons for fillings are many and can be prevented with constant care, but if your dentist recommends getting a filling, then heed his advice and get it done.