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When to Replace Old Dental Work

How do you know when you should have old fillings or crowns replaced? Are they supposed to last forever? Many people have fillings or crowns or bridges that last decades upon decades. It can be tough to know when or why to replace them.

This blog will describe the most common reasons that old dental work needs to be replaced. At Designer Smiles, we see dental work that is over 40 years old (thanks, Dr. Haggard!) and still doing its job perfectly. We also see crowns and fillings that are no longer doing their jobs and could lead to even bigger dental problems.

Anytime dental work requires replacement, our goal is for you to understand why. We never haphazardly recommend replacing all old mercury fillings or switching from an old gold crown to a porcelain one.

What are the Most Common Reasons that Dental Work Needs Replacement?

Part of each professional teeth cleaning visit is a dental evaluation of the teeth, gums, jaw joints, and all of the tissue lining the inside of the mouth. Both our fabulous dental hygienists and our dentists will assess the current state of your existing dental work to ensure that it is still doing its job.

When we say “doing its job”, we mean a few different things. The purposes of all dental restorations include: sealing the internal part of the tooth from bacteria, restoring the tooth to chewing function, and touching the neighboring tooth in a way that prevents food impaction.

New Cavities

One of the biggest misunderstandings we hear from our patients is their not knowing that you can still get a cavity on a tooth that has already had a filling or crown. The truth is that you are actually more likely to get a cavity on a tooth that already has dental work. The edge of a filling or crown, where it meets the tooth, is a high risk spot for plaque to collect and cause a new cavity. This is, by far, the most common reason we have to replace old dental work.

An Open Margin

The margin describes the edge of a filling or crown where it meets the natural tooth structure. This is the high risk spot for new cavities described above. We use he term “open margin” to describe an opening between the dental work and the tooth. This opening allows bacteria to seep underneath the dental work and cause new cavities more easily.

Open margins typically collect stain, so they will appear as dark lines around a tooth-colored filling. They are also visible on dental x-rays. An open margin is not the same thing as a cavity, but it is an area that will very likely become a new cavity at some point in the future.

A Crack in Either the Dental Work or the Tooth Itself

Just as an open margin allows bacteria to sneak into the tooth, so does a crack. People can develop cracks in the filling, which means the filling is no longer sealing out bacteria. We also commonly see cracks in the tooth itself, extending outward from the margin of a filling.

Cracks become more visible as they collect stain over time. Any opening that is large enough to collect stain is also collecting bacteria and becomes a high risk site for cavities.

Chipping or Attrition of the Restoration

Chipping and attrition (a slow, gradual wearing down of a dental restoration) are both signs of significant breakdown. Usually, the cause of both chipping and attrition is heavy clenching or grinding of the teeth. Remember that one of the important functions of a dental restoration is to restore the tooth to its normal chewing function. If it is chipped or worn away, it may not be adequately chewing your food. This can lead to problems with teeth shifting and the bite changing.

A Gap between the Dental Work and the Neighboring Tooth

Sometimes, small gaps can develop between the teeth. This occurs as a result of teeth grinding, gum disease, or changes in the bite. It leads to the impaction of food particles when you eat. Those food particles are a great source of fuel for the bacteria lurking between the teeth and, over time, cause cavities, especially right at the edge of your filling or crown. The food impaction is also an irritant to the gums, causing irritation and inflammation.

Replacing a filling or crown to close a gap between the teeth not only saves you the annoyance of getting food stuck between your teeth; it also lowers your risk for future cavities and gum disease.

Can I Just Wait until Something Hurts?

Well, you can . . . but we don’t recommend it. When you wait until something hurts, you allow the dental problem to progress to a state where the nerve inside the tooth is affected.

Many people say, “If it ain’t broke, don’t fix it.” Unfortunately, when it comes to dental work, “broke” doesn’t always equal pain. You can have relatively serious problems with dental work and no symptoms at all. Waiting until something hurts typically leads to dental work that is more extensive and more expensive!

How Can I Extend the Lifespan of My Dental Work?

You do have some say in when your dental work needs replacement. You can take measures to care for your dental work that will extend its lifespan.

Prevent Cavities

Because cavities are the most common reason dental work requires replacement, this is the most important step you can take to lengthen the lifespan of your fillings and crowns. Understanding that the edges of dental work (margins) are at a high risk for plaque buildup and decay strengthens our motivation to fight cavities.

Practice Great Oral Hygiene DAILY – This means brushing twice a day with an anti-cavity toothpaste and flossing every single night. Add a mouthrinse containing fluoride to strengthen your enamel and fight the attacks of sugar and acid.

Never Miss a Dental Visit – Your professional teeth cleanings and dental evaluations help prevent cavities by removing plaque and tartar buildup from the teeth and educating you on your high risk areas. Nancy and Phyllis will give you great tips on lowering your cavity risk by cleaning your teeth well. Dr. Ann and Dr. Lauren can catch warning signs and intervene to stop cavities before they start.

Lower your Sugar and Acid Intake – Avoid drinks that contain large amounts of sugar and drinks that are acidic in nature. Which beverages are acidic? Pretty much all of them. If it is not plain tap water, it probably has an acidic pH. Sparkling water, sodas, sports drinks, energy drinks, coffee, tea, wine, beer, kombucha . . . The list goes on forever. If you have extensive dental work, stick with water in order to make it last as long as possible.

Protect against Grinding/Clenching

If you clench or grind your teeth, Dr. Ann and Dr. Lauren will be able to tell. Bruxism (the scientific term that encompasses both clenching and grinding of the teeth) leaves telltale signs on the inside of the mouth. When they see these signs, they will discuss your risks with you and recommend a dental appliance to protect your teeth and gums from the damage caused by bruxism.

Commonly referred to as nightguards, these appliances can reduce the stresses and forces placed on dental work by bruxism and give them a much longer life. If you have one, WEAR IT! If you do not have one, GET ONE! A nightguard costs less than a single replacement crown and may save you from needing multiple restoration replacements over its lifetime. It’s worth it.

More Questions about When to Replace Dental Work?

Call today to schedule a consultation with Dr. Ann and Dr. Lauren. They can assess your particular dental work and advise you on any problem areas or warning signs they see.