What is a Dental or Rubber Dam?

Dental Dam in use

This is the dental term for the small sheet of rubber we place over teeth when we do fillings. It is often referred to by children as a “raincoat” or a “trampoline” and these nicknames are fairly accurate. Just as with a raincoat, the rubber dam is designed to keep a tooth dry while we work on it, and similar to a trampoline, our dam is a stretchy piece of rubber!

Why Do We Use a Dental Dam?

When working on teeth most of the filling materials we use must be placed into a tooth in a completely dry and clean work area. Saliva is not only moist, but it also contains certain materials that would contaminate the surface of the tooth to which we are gluing a filling. When we are bonding white fillings onto teeth, any contamination from either saliva or blood will result in the filling not lasting anywhere near as long as it is designed to.

Although the rubber dam was initially designed to help a dentist achieve excellent restorations, it is also there to make the patient’s experience in our chair more comfortable. Once the dam is in place, it stops water spray and little tooth bits or filling materials from falling into the back of a patient’s throat or being swallowed. It also blocks many of our bad tasting dental products from ever reaching the patient’s tongue.

One of the benefits for dentists is that it provides us with much better visibility to work on a tooth as it holds the tongue and cheeks out of the way and also eliminates the problem of having saliva bubbles cover the tooth and prevent us from seeing what we are doing. These are just some of the ways that we are able to ensure that dental procedures are done in a safe and effective way.

There is also an infection control aspect to using a rubber dam. Saliva contains a lot of bacteria. When we use a high-speed handpiece (a dental drill), aerosols containing bacteria are produced. These aerosols float into the air that everyone in the room breathes. By using the rubber dam, drilling takes place without any saliva contamination. The infectious component to these aerosols is reduced by over 95%. The use of a dental dam has been likened to wearing latex gloves during dental treatment with a similar impact on cross-infection. And, speaking of latex, for those that have a sensitivity or an allergy to latex products, a ‘non-latex’ version of the rubber dam is available. Please advise us if you require a non-latex version.

Many patients that have not seen a rubber dam prior to arriving in our office will ask if this is something new. In fact, dental dams have been around in some form or another for over 150 years. It was first described in the dental literature in 1864 when a Dr. Barnum from upper New York State punched a hole in an oil-cloth and tied it around the tooth he was working on. This kept saliva out of the way and allowed him to place the filling.

The popularity of rubber dams has gone up and down based on current theories of dental practice. There was a resurgence in the 1950’s for doing root canals when it was understood that the bacterial contamination from saliva was causing infections during treatment and reducing the success rate of treatment. Its use for routine fillings became popular again in the 1970’s with the start of bonding procedures and the use of the white composite filling materials. Through trial and error it became understood that without proper isolation, fillings were falling out after just a few years unless they were placed in a dry and contamination free environment.

Over the years the quality of the rubber has improved until today we have very thin and easy to work with latex sheets.

In order to have the dam fit over teeth, we punch holes in it to match the teeth that need to be isolated. The dam is then held in place in the mouth by placing a small metal ring called a ‘clamp’ onto the back tooth and sliding one of the holes that we have punched in the dam over the clamp. The other holes are then flossed between the teeth until all that shows through on our side of the dam are the teeth that make up our work site.

One downside of having a rubber dam is that it is harder for a patient to speak to us while we are working on a tooth. But, through a variety of non-verbal noises and hand signs, we are able to meet most of a patient’s requests. Also, based on our years of experience, you would be surprised as to just how much-garbled speech from underneath the dam we are able to understand!

Although there are other ways to keep a mouth dry while we are working, such as placing absorbent cotton rolls or gauze combined with vacuum suction systems, none are as effective or as successful as using the rubber dam. The way that it provides us with a combination of a clean and dry work area with greatly improved visibility allows us to achieve excellent and long lasting results with the fillings that we take pride in placing in your mouth.

Achieving excellence in all of our dental procedures is our ultimate goal, and our use of the rubber dam makes this task much easier.

If you have any questions on the rubber dam or on any of our dental procedures, please feel free to contact us for an explanation.

Dr. John

P.S. Join us on Facebook, for occasional updates and informative tips concerning dental health.

Leave comment

12 Avenue Brock Nord

Montréal-Ouest, QC H4X 2E9


Call us today!

Clinic Hours

Mon to Thurs – 8:00 am to 5:00 pm
Fri – 8:00 am to 4:00 pm
Follow by Email