Dental Materials Compatibility
Can't we all just get along?

by Louis Malcmacher, DDS

The title for this column may be an issue that you rarely think about, but it directly affects the dentistry that you do every day. The issue here is not communication with patients or staff, joining organized dentistry, or handling social obligations. The issue is dental materials compatibility. Are the materials that you use in your patients' mouths compatible with each other — i.e., do they all get along?

We live in a confusing world of dentin bonding agents, composite resin technologies, curing lights, resin-reinforced glass ionomers, compomers, curing lights, cements, and ceramics. How do you know that all of the components of the materials you use are actually working together harmoniously? The answer is you don't, unless you have a restorative failure and postoperative sensitivity.

When a restorative failure occurs, our natural inclination is to think that the dental material failed. We blame it on the resin or the bonding agent. Most dental manufacturers would like to believe that restorative failures are a result of poor dental technique. The answer, like so many other controversies, probably lies somewhere in the middle. A large part of the answer to this problem, however, likely lies within the realm of compatibility.

Let me give you an example. Most composite resins cure in a range between 350 and 600 nanometers. This is completely determined by the manufacturer; it is an area that most dentists don't even think about when buying composite resin.

Now, let's take a look at another crucial piece of composite resin bonding — the curing light. Currently, there are three major types of curing lights on the market — plasma arc, halogen, and light-emitting diode. A quick scan of these three lights in terms of their curing range would put them in this order: Plasma arc lights have the broadest range, meaning these lights will cure a very wide nanometer range and will cure probably close to 99 percent of all composite resins on the market. Halogen and enhanced halogen curing lights have a medium to broad range of curing composite resins, while light-emitting diode lights have a very short curing range, typically between 450 and 550 nanometers.

This doesn't mean that LED lights don't work. As a matter of fact, they have some advantages over other types of lights: They are typically cordless, lightweight, easy to use, and they produce no heat. However, because of their very short range of cure, these lights cannot be used successfully with many composites, only with those that are compatible. You may not realize this. Maybe you are curing composite resins that feel hard to the touch on the outside but are very soft on the inside of the restoration. To a certain extent, this is also true with bonding agents and composite resins and some ceramic materials and composite resins.

You need to know about your dental materials and whether or not everything is compatible. Sticking with one system from one manufacturer usually will solve this problem, but I completely understand the need for different materials in different situations. Do a little research; test these materials and lights in your own hands to make sure they are compatible with each other. This will significantly reduce restorative failures and postoperative sensitivity, which makes happier patients and happier dentists. Isn't it nice when we all get along?

Dr. Louis Malcmacher is an international lecturer and author, known for his comprehensive and entertaining style. An evaluator for Clinical Research Associates, Dr. Malcmacher is a consultant to the Council on Dental Practice of the ADA. For close to two decades, Dr. Malcmacher has inspired his audiences to truly enjoy practicing dentistry by providing the knowledge necessary for excellent clinical and practice-management skills. His group dental practice has maintained a 45 percent overhead since 1988.For details about his speaking schedule, Dr. Malcmacher can be reached at (440) 892-1810 or via email at dryowza@iname.com.
This article was originally printed in Dental Economics May, 2003
Author(s) : Louis Malcmacher

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