Rubber dams can bring back bad memories for many dentists. Most of us were required to use them in school or in our training programs and swore that we would never use them in the “real world.”

Early in my career, I had utter disdain for rubber dams and avoided them at all costs. However, I now use them routinely for a host of different procedures. Over time, I realized there are fundamentals to make the process of using a rubber dam efficient, effective and practical.

This has become especially true through the onset of the new coronavirus pandemic, as dentists have looked for ways to reduce aerosols while performing emergency treatment. In their recent algorithm for treating emergency patients during the COVID-19 pandemic, the ADA has included rubber dam use with a high-volume saliva ejector to reduce the spread of the highly contagious virus.

COVID-19 RESOURCES: We’ve created a new Spear Online resource page with practice management and clinical tools to navigate the COVID-19 crisis, so your team has the latest information to mitigate the financial impact and prepare to treat patients once operations return to normal.

By utilizing a rubber dam, we can minimize the aerosolized particles produced during patient care.

This helps to keep our teams safe when providing emergency care to patients who may spread viruses and other infectious diseases through airborne particles.

When are rubber dams useful?

Many different modern isolation systems are available for dentists, ranging from basic cotton roll isolation to more sophisticated isolation mouthpiece evacuation systems, such as Isolites. The rubber dam dates to the mid-1800s but still is the most ideal isolation system for reducing airborne particles and is still useful for certain clinical situations today.

Rubber dams can be very useful for everyday restorative dentistry procedures, such as cases where deep carious lesions present as a risk to pupal exposure, restorative procedures next to recent extraction sites and anterior cases where tissue retraction is necessary.

An example of a case in which rubber dams can be useful.
Rubber dams can be used next to a recent extraction site.
Rubber dams can be used in cases with possible pulpal involvement.
Rubber dams can be used in anterior cases where tissue retraction is needed to properly prepare the tooth.

Furthermore, when caustic solutions like hydrofluoric acid are being used intraorally for ceramic repairs, rubber dam isolation prevents damage to the adjacent tissues. Rubber dam usage is also still considered the standard of care for certain procedures, such as endodontic therapy.

Equipment to simplify placing and securing the dam

Looking back at why rubber dams used to be the bane of my existence, I realize many of my frustrations came from the fact that I didn’t understand the equipment to use to effectively place the dam.

One of my biggest issues was using the wrong clamp. There are many different clamps on the market, each of which can work well when used correctly. The two main categories of clamps are “winged” or “wingless.” Winged clamps have an extra lip built into the clamp design that can aid in retracting the dam. But these are bulkier than wingless clamps.

Wingless W8A and winged 14A clamps.

Both wingless and winged clamps are useful. Selecting one over another is solely a matter of preference. In general, I’ve found the following clamps to be most useful in our day-to-day practice:

  • W8A for maxillary molars
  • 14 A or W14 for mandibular molars
  • 12A for mandibular right molars, 13A for mandibular left molars
  • 2 for premolars
  • 9 for anteriors where retraction on the facial is needed for cavity preparation
W14 clamp.
12A and 13A clamps.
2 clamp.
9 clamp.

Clamps can fracture over time with wear and tear. This most commonly occurs at the bow of the clamp. To avoid a fractured clamp becoming an aspiration risk, it is recommended to ligate floss through one hole, around the bow, and through the opposing hole in the clamp.

Floss on clamp.
Clamp fractured at bow but held together by floss.

Another common issue is leakage of oral fluids through the dam. One way to mitigate this is by selecting the proper sized holes for the teeth being isolated.

Wheel on the rubber dam punch.

The first, largest hole is useful for molars that will hold the clamp. The second largest hole is a useful size for unclamped molars or clamped premolar teeth. The third hole is suitable for premolars, the fourth hole for canines and maxillary central incisors, and the fifth and smallest hole is useful for maxillary lateral incisors and mandibular incisors.

Knowing where to place the holes can also help minimize the chances of leakage and increase the efficiency of placing the dam. There are various templates and stamps on the market that can help determine where holes should be punched in the dam.

In general, holes should be about 4-6mm apart to ensure that the dam isn’t too stretched out or too loose between adjacent teeth. For patients that have malposed or crowded teeth, diagnostic casts of the patient can be used instead of a template to customize the location of the holes in the rubber dam.

Examples of stock rubber dam templates.
Examples of stock rubber dam templates.

Invariably, leakage may still occur. A caulking material can be utilized to seal any areas that may still present with leakage after the rubber dam is placed. Various products on the market are available for this, however unbonded composite can also be placed and light cured to act as a caulking agent.

Techniques to simplify placing and securing the dam

Placing the dam intraorally can also present as a challenge since the dam can fold upon itself when trying to place it on the teeth. In order to simplify this, the dam can be attached to the frame before it is placed in the mouth. This keeps the dam taunt, making it easier to facilitate placement intraorally.

Dam on frame before placement in mouth.
Dam on frame before placement in mouth.

While it is not always necessary, a lubricant can be utilized to facilitate placement of the dam. Various materials, from glycerine to shaving cream to soap, have been suggested for lubricating the dam. Vaseline should be avoided, since it can weaken the dam material, which leads to ripping and tearing of the rubber dam.

Floss should be used to push the dam through the contact areas of the teeth. After passing through the contact point, the floss can be used to help invert the dam by gently working the floss in to the gingival sulcus. Pulling the floss out buccally, rather than back through the contact point, can help minimize the risk of having the dam dislodge from the tooth.

In some instances, light or open contacts may exist between adjacent teeth. This can present as a challenge for securing the dam. Fabricating a floss ligature using a square knot can help to secure the dam around the tooth. If this does not work, a thicker material can be used (such as a Wedjet) to hold the dam in place. Alternatively, a corner of the dam can be cut off and used interproximally to secure the dam.

Floss ligature and Wedjet.
Corner of the dam.

Using a rubber dam doesn’t have to be a challenge. Knowing the right materials and techniques to use can simplify the process of using a rubber dam, and in turn can help make dentistry easier for us and our patients.

Andy Janiga, D.M.D., is a contributor to Spear Digest.


Commenter's Profile Image Jonathan C.
April 23rd, 2020
Good stuff. If someone really wants to elevate their rubber dam game, I'd encourage them to check out, Dr. Calin Pop. He is to rubber dams what Dr. Frank Spear is to provisionals. Thanks for the tips.
Commenter's Profile Image Andy J.
April 23rd, 2020
Thanks Jonathan!
Commenter's Profile Image David S.
May 12th, 2020
Great review!!
Commenter's Profile Image Andy J.
May 12th, 2020
Thanks David!
Commenter's Profile Image Chris F.
June 10th, 2020
Nice, thanks for the article Andy
Commenter's Profile Image Sarah K.
June 16th, 2020
very helpful article!! thank you!
Commenter's Profile Image Andy J.
June 17th, 2020
Thanks so much!
Commenter's Profile Image David K.
September 10th, 2020
Somehow I have used rubber dams since graduating in 1978. I find it a lot less stressful. Not worrying about moisture, tongues etc. and most patients tolerate it and a lot like it. Many times I can image with the dam on except obviously for the bite. Here are my two additional cents: #18 wingless lower first molars #14A upper first molars #8A upper seconds W2 bicuspids. Anterior clamps use hygienic 9. To make finding the holes easier since the dam gets twisted when putting on, by convention, we always punch two holes in the lower left corner so I always know that is the lower left. I most always clamp one tooth distal to the tooth I am working at and then to the contralateral central. That way when I am placing and trying to figure out which hole goes on what tooth, can easily match up the holes. Do not use the lightest weight dam material as it tears too easily. I use medium. They make some pretty goofy rubberdam forceps. Don't use the ones that have a curve beak as once the clamp is on it is difficult to take off do to the angle of the forceps. I used to have these nice straight forceps which had grooves to keep the retainer from slipping. Somehow they disappeared in sterilization. I now have straights with no groove - pain in the butt as the retainer slips. I will either cut my own or see if I and find a set that does.
Commenter's Profile Image Robert S.
October 13th, 2020
Thanks for the helpful article! I've been thinking about using a rubber dam more for improved isolation. Thank you for the ideas!
Commenter's Profile Image Naomi S.
October 30th, 2020
Awesome review, very informative.