Dental MythBuster #13: A Dental Filling Will Last Forever

Fortunately, this dental myth does not come up very often. When it does, the myth usually comes up when I have to deliver news along the lines of “I have a concern about one of your fillings.”

Most patients understand that dental fillings are usually not lifelong permanent solutions. But some patients don’t. Like many other medical devices and appliances, fillings don’t last forever.

Problems with Dental Fillings

There are all types of problems that can occur with dental filings. Below are some examples:

broken mercury amalgam filling in a tooth

A broken silver amalgam filling. This will need to be replaced.

The tooth above shows two premolar teeth, both with amalgam fillings. One of the fillings has cracked. There are many reasons why it cracked – but they go beyond the scope of this post. However, to summarize, after being chewed upon several hundred thousand times, it has finally failed.

high quality photo of broken lower molar tooth with a filling

Here, both filling and tooth broke!

In this photo, a large portion of both tooth and filling broke. In this particular case, the filling had been there for over 20 years, but the remaining tooth structure was so weak it finally gave out. In this case, this patient needed a crown.

In addition to the above two examples, dental fillings can fail for many other reasons. And many will fail due to a combination of multiple factors.

What other medical appliances last a lifetime?

On occasion, I will come across a patient who is particularly disturbed that one of their fillings done during the Clinton presidency needs to be replaced. I will often politely respond by referencing other medical appliances:

cardiac pacemaker is like a filling and can last seven years

On average a pacemaker lasts seven years.

What do the above 3 devices all have in common? These are all manmade devices designed to replace or repair damaged or missing human tissue. And that is exactly what a filling is.

When I mention these examples, most patients begin to understand fillings typically have a finite lifespan. And then the myth is busted…

How Long Should a Filling Last?

This is difficult to answer since there are so many factors at play. I’ve seen fillings last over 40 years while others fail within 1 to 2 years. The factors can include:

  • Type of material (silver amalgam vs. resin composite).
  • Location in the mouth.
  • Oral hygiene.
  • Sugar intake.
  • Occlusion (how the teeth come together).
  • Skill level and attention to detail of the dentist who placed it.

So, while occasionally a filling can last a lifetime, that is not the norm. Just like nearly all other medical appliances and devices, they can and do wear out. It is a myth that all fillings will last forever.