Complete Family Dentistry Blog - Waukesha , WI
Posts for tag: fillings
Dental amalgam—also known as “silver fillings”—has been used for nearly a hundred years to treat cavities. There are several reasons why this mixture of metals has been the go-to material among dentists: Malleable when first applied, dental amalgam sets up into a durable dental filling that can take years of biting forces. What’s more, it’s stable and compatible with living tissue.
But there’s been growing concern in recent years about the safety of dental amalgam, with even some wondering if they should have existing fillings replaced. The reason: liquid mercury.
Mercury makes up a good portion of dental amalgam’s base mixture, to which other metals like silver, tin or copper are added to it in powder form. This forms a putty that can be easily worked into a prepared cavity. And despite the heightened awareness of the metal’s toxicity to humans, it’s still used in dental amalgam.
The reason why is that there are various forms of mercury and not all are toxic. The form making headlines is known as methylmercury, a compound created when mercury from the environment fuses with organic molecules. The compound builds up in the living tissues of animals, particularly large ocean fish, which have accumulated high concentrations passed up through their food chain.
That’s not what’s used in dental amalgam. Dentists instead use a non-toxic, elemental form of mercury that when set up becomes locked within the amalgam and cannot leach out. Based on various studies, treating cavities with it poses no health risks to humans.
This also means there’s no medical reason for having an existing silver fillings removed. Doing so, though, could cause more harm than good because it could further weaken the remaining tooth structure.
The most viable reason for not getting a dental amalgam filling is cosmetic: The metallic appearance of amalgam could detract from your smile. There are newer, more life-like filling options available. Your dentist, though, may still recommend dental amalgam for its strength and compatibility, especially for back teeth. It’s entirely safe to accept this recommendation.
With all the new tooth-colored fillings for cavities, it's easy to overlook metal amalgam. While this mainstay of dental care for over a century might not be as attractive as composite resins or glass and resin ionomers, it still has the advantage of strength and durability.
Amalgam is a stable metal alloy usually made up of silver, tin, copper and mercury. The metals are proportioned and mixed precisely to guard against “free” mercury molecules, which could pose a health hazard. The mixture is pliable at first, but then sets hard once molded into the prepared area of the tooth.
Besides strength, amalgam's other advantages include low cost, high resistance to wear and biocompatibility (not toxic to the body or allergy-producing). At the same time, it can require more tooth structure removal to accommodate a filling and cause higher sensitivity to temperature for a while after installation. Its main disadvantage, however, is appearance — it's now considered unacceptable from an aesthetic point of view to use it in visible areas like the front teeth.
Because of this, materials resembling natural tooth color are coming into vogue, especially as their strength improves. Still, dental amalgam continues to play a useful role, especially in less visible back teeth with higher chewing forces.
One past concern about dental amalgam is the inclusion of mercury in the alloy. As mentioned before, mercury is hazardous in a “free” form when not knit microscopically with other metals; as such it can emit a vapor that could enter the bloodstream and damage the nervous system. But after several studies by various organizations, the American Dental Association has concluded amalgam's precise mixture prevents the mercury from taking this form: although some vapor is given off during chewing it's far too low in concentration to pose any danger.
Dental amalgam continues to be an effective choice for fillings. Whether it's the right choice for you will depend on the type and location of a tooth to be filled, and whether durability is a higher concern than appearance. If we do recommend an amalgam filling, you can be assured it's a safe and lasting choice.
If you would like more information on your choices for dental fillings, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Silver Fillings — Safe or Unsafe?”
For over a hundred years dental amalgam — a combination of silver, mercury, tin and other metals — has been an effective filling material for teeth damaged by decay. But it has one major drawback — its metallic appearance stands out in stark contrast to the natural color of teeth.
As an alternative, composite resin fillings can match the color, shape and texture of natural teeth. These materials and the techniques used to bond them are proving just as effective as and more aesthetically pleasing than dental amalgam.
Fillings help protect and preserve a decayed tooth. By first removing decayed tooth structure through drilling, the resulting void is filled with durable material that strengthens the tooth and provides it protection from further decay.
The ultimate goal for restoration is to return the tooth to as near normal form and function as possible. Dental amalgam serves well in terms of function, providing the tooth strength in the face of the daily biting forces it encounters. In contrast, composite resins excel in appearance, but haven’t always matched the durability of amalgam. They’re material construction has improved over time, though, as well as the techniques used to bond them to teeth.
Most of these bonding techniques incorporate layering. The first step is to seal the dentin (the porous, living tissue just below the enamel); we then build up the composite material layer by layer within the tooth using special bonding adhesive and curing lights. In some cases where a large volume of tooth structure must be replaced, the restoration is first formed on the tooth and then removed for curing before being cemented into the tooth or a separate restoration is formed by a dental lab.
The end result is a tooth which both looks and functions like a fully intact tooth. Though care must be taken not to subject composite resin restorations to undue forces (no cracking open nutshells, for example), your new filling should continue to serve you and look great for a long time to come.
If you would like more information on metal-free restorations, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “The Natural Beauty of Tooth Colored Fillings.”
Metal amalgam fillings for dental caries have been used since the mid 19th Century. Although newer, “natural color” filling materials have become available, amalgam remains a standard choice among dentists.
Dental amalgam is a metal alloy created by carefully combining exact proportions of mercury, silver, tin and copper. Though quite pliable when first mixed, the alloy eventually sets into a very hard substance that stands up well against the forces produced by the mouth’s natural chewing function. The presence of mercury, however, has raised concerns for some that the metal’s toxic properties pose a risk to the patient’s health.
But after decades of research, the American Dental Association and other health organizations have concluded that dental amalgam “is a safe, reliable and effective restorative material.” Studies have determined that any free molecules of mercury that could potentially enter the bloodstream are trapped in the set amalgam. And although the amalgam can release mercury vapor during chewing, the amounts are well below the levels considered harmful.
Dental amalgam has proven to be versatile, effective and economical. It doesn’t create an allergic reaction, is quite durable, and doesn’t interfere with normal chewing function. It does, however, have its drawbacks. Its use can require more tooth material to be removed to keep the fillings in place, and they can increase temperature sensitivity during the initial four to six weeks. And, of course, their metallic appearance, especially when used in more visible front teeth, reduces their aesthetic appeal.
Other, more cosmetically appealing types of filling material have been developed over the years. These include composite resin fillings, a mixture of glass or quartz in a resin medium; glass ionomers, made of acrylic acids and fine glass powders and best used in areas not subject to heavy chewing; and resin ionomers, similar to glass ionomers but with the addition of acrylic resin. Each of these has their advantages and disadvantages (as well as cost considerations), but they’re main advantage over amalgam is their mimicry of natural tooth color.
The choice of either dental amalgam filling or one of the tooth-color alternatives depends on what you may need and can afford. Rest assured, though, that if the choice is dental amalgam, this restoration workhorse can provide you years of safe and effective service.
If you would like more information on your options for tooth fillings, please contact us or schedule an appointment for a consultation. You can also learn more about this topic by reading the Dear Doctor magazine article “Silver Fillings.”
It used to be that when it came to treating tooth decay (cavities), your primary option was to have the tooth decay removed and filled with a metal amalgam (silver-colored filling). This treatment sometimes requires a special shape cut called an “undercut” to be drilled into the tooth to hold it in. Unfortunately, it can also involve removal of some healthy tooth structure. Silver amalgam fillings still have limited applications and are still used in back teeth where they don't show in the smile. This is because they are strong and resist biting well; however, over time they can fatigue and fracture.
Older restorative concepts were based upon the development of strong and stiff materials such as gold, which tends to be unyielding and therefore contributed to failures of the remaining tooth substance around restorations (e.g., decay or cracking). Newer concepts tend to get away from the “stronger and stiffer is better” concept and have moved towards safety principles using materials that involve mimicking the properties of natural tooth structure. In fact, it is now clearly established that a new “biomimetic approach” (“bio” – life; “mimetic” – mimicking) to dentistry is possible through the use of tooth-like materials such as composite resins and porcelains. And unlike metal alloys, these newer materials bond directly to the remaining enamel and dentin of which the teeth themselves are made, which both stabilize and strengthen teeth.
These techniques are also suitable for children's teeth and can incorporate fluoride to reduce further decay. But perhaps best of all, using these materials and more modern technologies can restore proper tooth function and normal wear while producing results that appear indistinguishable from natural teeth.
To learn more, continue reading the Dear Doctor magazine article “The Natural Beauty of Tooth Colored Fillings.” You can also contact us today to schedule an appointment to discuss your specific questions about replacing your metal fillings with tooth-colored ones.