What kind of materials are available to fix holes in teeth?

The most common material for about a century has been silver and copper mixed with mercury with a little tin.  This mixture is called amalgam or simply silver filling.

Silver has anti-microbial propertities that helps prevent bacterial growth.  The copper and tin control the amount of expansion and contraction that occurs to reduce the number of teeth that crack with filling expansion.

The most controversial part is the mercury.  Mercury in its purist from can dissolve other metals to form an alloy at room temperature.  This makes it unique.

Unfortunately, when mercury combines with other materials like fats or carbohydrates, it can be more easily accumulated from the environment.  Many fish have accumulated enough mercury in their tissues that eating too much fish can be bad for you.

Mercury released from silver fillings has been extensively studied and concluded to be safe.  The amounts released are very, very little and the form of mercury is not easily combined with our tissues.

Neverthe less, many people prefer not to have silver fillings for fear of even the smallest amounts of mercury, because the fillings are dark, and because they can crack teeth after many years.

The next most common filling material is composite plastic.  A composite is a mixture of several materials and the materials mixed for this filling is plastic and extremely finely ground glass.

Recent concerns about bis-phenol A in plastic packages has caused some concern about the plastic in fillings.  Dental fillings use bis-phenol B.

The advantages of Composite fillings:

• they look great
• have the ability to stick to tooth structure,
• wears well
• it insulates from hot and cold,
• there is no problem biting metal foil.

The disadvantages of composite fillings are:

• they are very sensitive to getting wet during placement,
• that they can stain,
• they are not as strong,
• the bond to enamel may break down over time and allow bacterial to seep under the filling.

Some alternatives to composite are glass ionomer fillings, ceramic or gold cast inlays, or crowns.

Glass ionomer fillings are made of polyacrylic acid and finely ground glass particles that contain fluoride.  There have not been any reports of toxicity of these materials.

They are most commonly used for temporary fillings or fillings that are difficult to keep dry.  Many third world countries use glass ionomer fillings placed by non-dentist technicians to stop decay for many years. 

The disadvantages of  glass ionomers are:

• They can be brittle and crack
• They wear down fairly quickly

Advantages of glass ionomers are:

• Easy to place
• Release fluoride to reduce decay
• look tooth-like
• insulate from hot / cold / foil

The least common alternative to fill cavities is the use of customized precision-ground ceramic materials cemented in place with composite or pure gold fillings pounded into the hole or cast and cemented.

These are all very expensive and with the exception of the pure gold foil, they are cemented in place and have the same complications of composites mentioned above.

What it all comes to is that preventing a cavity is infinitely better than fixing one.

Post from: Great Grins

Filling Materials

A child from Molalla came to the Oregon City office recently with just such a problem.

This little boy had cavities on almost every one of his baby teeth and most of the decay was very close to the pulp nerve tissue and probably needing baby root canals (pulpotomies).

Recently published articles recommend an Alternative Restorative Treatment (ART) to removing all the decay and filling with permanent restorations.

They strongly recommend trying to stop the decay from progressing into the nerves by scooping out some of the rotten tooth material on every tooth during one short appointment and filling the holes with glass ionomer.

Click here for more information on glass ionomer fillings.

There are several advantages to this technique:

1. The filling provides fluoride to strengthen the tooth and keep germs from growing the decay deeper.
2. All the cavities are stabilized so fewer germs are spreading around the mouth and infecting other teeth.
3. Leaving some of the rotten tooth under the filling provides a separation that permits the nerve to heal and back away from the decay.
4. It costs less at our office through a special Glass Ionomer Caries Control program we have developed that caps out of pocket expenses.

We used this ART with the little boy from Molalla.  He now can grow older without pain and then replace the ART with definitive restorations as his patience, and parent finances, allow.

I would call this a win-win-win situation.

Post from: Great Grins

ART: Alternate Restorative Treatment