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Do You Need To Replace Amalgam Fillings In Houston, TX?

If you have silver fillings, it may be time to say goodbye to them and hello to new composite ones.

By Jennifer
Photography by Pete

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It’s almost inevitable that at some point or another that you will need a dental filling. Nearly everyone gets at least one cavity in their lifetime, with patients as young as 2 and as old as 92 needing to see our dentists for treatment. Depending on the severity, your dentist may recommend a filling when a tooth is:

  • Decayed to the point that there is a physical hole in the tooth
  • Chipped, cracked, or fractured
  • Damage from tooth grinding

Since their invention in the early 19th century, dentists have traditionally used silver dental amalgam for restoring a tooth against decay with a cavity filling. However, as dentistry has come further along in the following centuries, there are now several alternative materials that we can use instead. The most popular of these new materials is composite resin. Recently, the dental world has almost entirely abandoned amalgam for this tooth-colored upstart.

Why Is Composite Better Than Amalgam?

Amalgam fillings are made of about 50% liquid mercury, with other metals like tin, copper, and silver making up the other half. This material used to be the cavity filling of choice due to its longevity, strength, and resistance to wear and tear. They were also often used for larger cavities, which require greater strength to reinforce the tooth against future tooth decay, cracks, chips, and dental damage.

However, their high mercury content has put these fillings under scrutiny among both dentists and patients out of safety concerns. Amalgam can release trace amounts of mercury vapor that can be breathed in and absorbed into the lungs. While dangerous in high amounts, this vapor is relatively harmless in the small doses that these fillings release. Still, the FDA warns there is a greater risk among pregnant and nursing women, children under 6, and people with existing neurological diseases or impaired kidney function.

Beyond the health concerns, amalgam fillings have largely fallen out of fashion for several other reasons:

  • Silver fillings do not look natural and can be easily seen
  • The filling can gradually discolor the surrounding tooth an unnatural, unhealthy-looking gray
  • The metal can expand and contract over time with heat and cold, eventually causing the tooth to crack
  • Dental amalgam requires more of the original tooth to be removed to fit the cavity filling
  • Some patients are sensitive or allergic to mercury and other metals used in amalgam fillings

In recent years, dentists across the country have switched almost entirely to composite and other metal-free alternatives. Composite fillings use a liquid resin made from plastic and ceramic compounds. Once they are applied to the tooth and molded into the best and healthiest shape, the resin is hardened with a curing light to seal the tooth fully. These fillings are the most popular not just because they avoid using the same controversial materials. They can also look just like the surrounding tooth. Composite can come in many shades, so a dentist can choose the one that perfectly matches the natural tooth.

Previously, these tooth-colored fillings were mainly used for front teeth, while amalgam was placed on back teeth. At Nu Dentistry, we only use composite fillings so that our patients can enjoy a natural-looking, healthy smile. Composite has improved drastically in strength over the years, with greater strength and durability. Nowadays, these fillings can safely take on even the increased bite pressure that back teeth and molars face daily.

Here’s a quick look at the pros of composite fillings:

  • Aesthetically pleasing
  • Entirely metal-free
  • No health and safety concerns
  • Bond to the tooth’s surface for greater support and stability
  • Adequate strength, no matter the tooth’s location
  • Requires less tooth preparation than amalgam
  • No contraction or expansion of the filling over time
  • Easy to replace
  • Hardens quickly for a quick procedure

When Should Amalgam Fillings Be Replaced?

While you can often choose to have our dentists replace your amalgam fillings with composite ones, sometimes life makes that decision for you. As great as you may take care of them, even the best dental fillings don’t last forever. Eventually, they will need to be replaced as they gradually break down over time. How long do fillings last? Typically, amalgam fillings last about 15 years before patients need to replace them. Composite fillings last between 8 and 12 years on average. Leaving your old and worn-out fillings is a recipe for disaster as it leaves the inner tooth exposed and vulnerable to dental decay and further damage.

These are some of the most common warning signs to look out for if your tooth filling has been compromised:

Missing Filling One of the most obvious signs to see your dentist is if your filling fell out. With a missing filling, it’s critical to get it replaced as soon as possible. The inner tooth below is left exposed and vulnerable to cavities, decay, and further injury.

Crack In Your Filling Over time, constant pressure from eating and biting can cause dental fillings to crack. While some cracks can be visible, others may be small or thin enough only to be seen with an X-ray. However, no matter their size, these cracks should be re-filled quickly as they can become infected.

Toothache If your already-filled tooth starts hurting again, it’s probably time to get your cavity filling replaced. Toothaches are a common sign that the filling has been compromised, and tooth decay has started attacking your sensitive inner tooth. If left untreated, the decay will spread and continue to worsen until you need something more extensive than a simple filling, like a dental crown or root canal.

Sensitivity The filling needs replacement when the tooth gets sensitive to hot and cold. Sensitivity in filled teeth is often a sign that the filling or the tooth around it has a crack. (Please note that it’s normal to experience some measure of sensitivity days or even weeks after first having a filling performed.)

Tooth Injury Sometimes, it’s not the filling that’s the problem but the tooth itself. If the tooth breaks due to injury or trauma, your current filling won’t work. A new dental filling is needed to repair and reinforce the tooth.

It is not always easy to self-assess when your filling needs a replacement. The best way to know for yourself is to visit your dentist for an examination.

How Many Times Can A Filling Be Replaced?

The exact number of times a dentist can replace your dental filling depends on how much of your base tooth remains. During the filling procedure, the decayed and injured portions of the tooth are removed before the hole is filled with composite resin. If that hole becomes too large, the tooth is too weak to stay strong and protected against future damage. Sometimes, a tooth has multiple fillings, meaning even more of the original tissues are missing. In these cases, your dentist may eventually recommend a more extensive restorative treatment, like a porcelain dental crown, to reinforce the whole tooth.

How Are Fillings Replaced?

When replacing an amalgam filling with a composite one, the procedure is similar to the initial filling. It will just take a bit longer as we will first need to take out the old tooth filling before preparing and placing your new one.

  • First, we numb your tooth with a local sedative so that the entire process is painless.
  • Next, the old filling is removed via a dental drill.
  • Once the cavity is cleaned off the old residue, it is prepared again to fit in the new one. With teeth that have developed new infections and cavities, this may require removing more of the tooth.
  • The composite resin is placed before being hardened with a special light. This is done in layers.
  • After the tooth is filled, we will shape the composite filling until it fits your bite perfectly, making adjustments where needed.

How long does a filling take? Most fillings don’t need more than an hour to finish, including the time necessary for the local anesthetic to kick in. However, the exact time depends on the size of the dental filling needed. Small fillings might require as little as 20 to 30 minutes to complete, while larger or multiple fillings may need quite a bit longer.

Do you need to replace your current silver fillings with metal-free composite? Feel free to give our dental office a call at (NUMBER) today to schedule an appointment with our dentists.

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