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Back 19 June 2017

Mercury & Amalgam Silver Filling Removal

While mercury amalgam (aka silver, metal or black) fillings have been a mainstay cavity solution for more than 150 years, new dental techniques and technology have enabled the development of durable, high strength alternatives that include composite resin white fillings, dental crowns and porcelain overlays.

At Milford Dentists, we have used these more natural-looking materials for filling teeth cavities for more than 30 years and have opted to be mercury amalgam free since 1999. For a variety of reasons, a growing number of prospective and existing clients are requesting amalgam filling removal and replacing the silver with more aesthetically appealing white composite.

To help answer some of the many questions asked about silver filling removal we’ve compiled a simple FAQ guide below. And if there’s anything else you need to about removing mercury fillings, don’t hesitate to make contact here or call us on (09) 489 6575.

What Are Mercury Amalgam or Silver Fillings?

Although more commonly known as silver fillings, amalgam fillings contain very little silver. Instead, amalgam fillings are made from a variety of materials – a powdered alloy of silver, tin, zinc and copper, with liquid mercury making up almost 50 percent of the compound.

Mercury is used to bind the alloy metal particles together, resulting in a strong and durable filling for dental cavities.

Are White Fillings Better Than Amalgam?

Today there is a wider variety of dental filling materials available. Your teeth can be repaired not only with mercury amalgam but also gold, porcelain, or our preferred choice - natural tooth coloured composite resin fillings.

These composite or white fillings are a combination of tooth-coloured plastic and glass that are free of toxic substances and customisable to match your teeth, so are suitable not just for restoring decayed teeth, but also for cosmetic improvements.

While the FDA currently considers dental amalgam fillings safe, many clients prefer to have their fillings replaced with composite resin or choose white fillings for new and future dental repair work.

Why Choose White Fillings?

For almost two decades Milford Dentists have been using improved tooth coloured composite resin fillings and advanced bonded (or adhesive) dental techniques to mimic the strength and appearance of your original tooth. These composite white resin restorations are very strongly bonded to your teeth and make the tooth almost as strong as it was before decay occurred.

Amalgam fillings, however, are not actually attached or bonded to your tooth; they simply fill the gap where the cavity has been removed and do not strengthen teeth. An amalgam filling acts like a wedge. When biting down on the filling, the forces are transferred to the remaining tooth structure. This issue of twisting, bending and flexing of the amalgam filling occurs daily on teeth during ordinary chewing, putting further stress on amalgam fillings.

Also, when the amalgam filling heats up and expands (e.g. while drinking coffee) or cools down and contracts (e.g. while eating a frozen dessert), gaps open up around the filling - risking cracks and stress fractures in the tooth structure.

When using white coloured composites, the adhesion to the tooth means that if chewing or biting down, the force is distributed across the tooth structure more evenly than it is with amalgam fillings, reducing the likelihood of tooth cracking or fractures.

Consequently, when replacing old mercury amalgams with tooth coloured filling or porcelain crown/overlay, our team have frequently discovered undiagnosed cracks, fracture lines or decay.

And, many of these issues are not visible on the tooth surface or by x-ray.

xrays for white fillings

Why Are Cavities Difficult To Identify Under Amalgam Fillings?

Because of their metal content, silver fillings are opaque to x-rays and therefore cavities below the fillings are difficult to identify (unless quite substantial). Industry experience has shown that without x-rays, only as much as 50% of these dental issues are visible during an examination and full x-rays will only display 80-85% of issues. 

The Benefits of Composite White Filling Bonding

At Milford Dentists, we have adopted the bonding process of pioneering US dentist Dr Dave Allerman that recreates the join between enamel and dentine to strengthen the tooth. We also, in certain circumstances, have utilised his protocol that bonds tooth fractures together using a high strength Ribbond mat – a material similar in structure to Kevlar used in bullet proof vests. As a result of implementing these processes, when replacing mercury amalgam fillings with white composite resin, the tooth can become stronger - almost as strong as the healthy tooth prior to decay.

What is The Procedure for Silver or Amalgam Filling Removal?

If you wish to cosmetically improve your smile or have concerns over your health with regard to existing amalgam, our staff can discuss with you the safe and easy removal of silver fillings at a consultation.

At Milford Dentists, during a single visit we can safely remove several amalgam fillings if required and use metal free alternatives to reconstruct your smile with either tooth coloured composite resin or porcelain CAD/ CAM E4d overlays, onlays and crowns.

1. Patients, when requested, receive oxygen to prevent inhalation of any mercury vapour or amalgam particulate during the procedure.

2. A dental or rubber/nitrile dam is placed and sealed over the tooth or teeth being worked on to isolate them from your mouth - essentially the rubber dam sheet when inserted keeps your tooth "outside your mouth during the procedure creating a very thin barrier. The dental dam makes the bonding process of creating long-lasting, beautiful restorations more predictable, quicker and easier to complete.

While using the rubber dental dam, a small yet powerful suction pipe or saliva ejector also removes any mercury vapour, saliva and amalgam particles or slurry from the the rubber dam working area.

3. The filling is then drilled out in chunks  (chunking or sectioning) These “chunks” can then easily be removed by a hand instrument or suction.

This process requires less drilling because our dentists only drill enough to segment the filling into chunks.

4. During the amalgam removal process, the drilling of amalgam fillings generates significant heat, which can cause an increase in the release of mercury vapour. To minimise this vapour release, the filling, whilst being removed, is cooled with water and air.

We are happy to work with your health practitioner who will often augment our dental treatment with IV or tablets of vitamin C, charcoal scavenger tablets, chlorella, etc.

If you want to know more about amalgam filling removal - get in contact here or call us on (09) 489 6575.

Posted by Andrea