I read filling need to be replaced every ten years. How do you know when fillings need to be replaced? I had some filling put in when I was 8-20 years old. I am now 23. Should these be replaced?
When the dentist tells me they need to be replaced.
ETA: Seriously though, do you not go to the dentist? And what do you mean, you had filling when you were “8-20”? Does that mean you had them every year between those ages? I don’t understand how you are asking, on the premise that filling should be changed every 10 years, if your fillings should be replaced when you only give a very vague age range for when you got them?
I know when my dentist tells me that’s the case.
My sister has some fillings over 40 years old that are still in good condition.
It will vary with the type of filling, how the tooth is used, and other factors. There is no one answer that applies to all. Ask your dentist.
I seriously doubt the reliability of wherever you ‘read’ that.
I have fillings that are much older than you are, that my dentist says are still fine.
They could break, loosen, or fall out over time, but they look at them during your cleaning/exam. I lost half a filling once, but I didn’t realize it until the dentist told me. I’m sure he’d tell me if I needed any others re-done. More business for him, after all.
If it ain’t broke, don’t fix it! (But do see your dentist regularly.)
sorry i meant to say i had them done at 8-10 years old. I go to the dentst every 6 months but I had a friend who moved to florida, the same age as me who when they got a exam down there found out they needed 3 root canals because there dentist up here never told them they needed them replaced.
You just can’t compare. For all you know, the dentist who did your friend’s fillings al those years back may have been sloppy, but your dentist did excellent work and your fillings might be good for another 20 years.
It really is going to be a unique case for each tooth in each person’s mouth.
Interesting. I’ve never heard of old fillings being a cause for root canal work. Maybe that is the case, but I can’t help but wonder if there was misunderstanding about what your friend was told, or if there was truly a need for the root canals.
I usually know that I need a new filling when my old one falls out.
By any chance did your friend lose his fillings and not get them re-filled? That would make the root canals more understandable.
I had many twenty year old fillings in my late 30’s and generally did not replace mine until they fell out; didn’t go to the dentist for a few years there. Costly mistake; they got loose and allowed decay down into the tooth and many a root canal were required. I luckily got a job with great insurance and a FlexCare Plan; had about $15k in crowns, fillings, veneers and a bridge installed. Lost a few teeth. Now I treat my teeth like the jewelery I used to have (and had to sell for teeth). 
My dentist crows about his great masterpiece of work and praises my diligent maintenance every time I see him (2-3 times a year now).
Perhaps the OP’s question could be re-interpreted to mean: How long could a filling last?
Potentially, for the rest of you life. I have many fillings that are 40++ (maybe even about 50) years old. One has fallen out and needed to be replaced. Three others needed to be replaced (very recently) because (I think) of other new decay in those teeth. One or two others needed to be replaced, at one time or another, for various reasons. I think one got chipped or something.
But I still have others that are still there, with no known problems.
It also depends on the type of fillings you have. The mercury amalgams last longer than the newer type of fillings. But even my old mercury fillings from 30-35 years ago started “bleeding” into the enamel of my teeth - that required replacement. The amalgams slowly expand over time and can actually cause teeth to split - so I am slowly having mine replaced with them there new white fillings (they harden with UV light). I can’t come up with the name of them, it’s killing me. These are only supposed to last 10 years or so. I’m trying to chew gently…
Oh, and also you may want to rid yourself of the mercury if you’re concerned about that sort of thing. Not sure what the exposure is, but if the fillings are older and cracked, there is some off-gassing of Hg.
[QUOTE=CrabRangoon]
…new white fillings (they harden with UV light). I can’t come up with the name of them, it’s killing me. These are only supposed to last 10 years or so. I’m trying to chew gently…
[/QUOTE]
Composite resin.
Long-term durability of composite materials is still somewhat unknown. This page from dental insurance giant Delta Dentalsays the newer more durable composites have only been available for a decade, so claims to last longer than that are currently just conjecture.
The same pages describes an 8-10 year lifespan for mercury amalgam as well, but says they may last 20 years or more.
Personally, I think Delta is being insanely conservative. I have composite fillings on molars that are approaching 20 years old, and I’ve got one amalgam filling that’s been with me for about 30 years.
The FDAdoes not recomment replacing undamaged amalgam fillings, saying the process of removing them and replacing causes unnecessary loss of healthy tooth and exposes you to mercury vapor as the filling is drilled out.
There’s also a few shyster dentists out there who will claim a patient “needs” XYZ procedures/treatments, but they really don’t. Your friend’s fillings may have been just fine, but the dentist is trying to shake him/her down.
I had an experience where my regular dentist had a stroke and had to sell his practice. So I went to the new dentist who’d bought my dentist’s practice. I have very little dental work and really healthy teeth and had been going to my old dentist every 4 months for about 5 years. This new dentist claimed that I needed a deep-clean root scaling, four brand new fillings, and three old ones needed replacing. He presented me with an estimate of just short of $2000. This office did not accept my dental insurance.
I looked that con artist right in the eye and said, “So… let me get this straight. I’ve been going to Dr. [old dentist] every four months for several years and you’re telling me that he was such a lousy dentist that he never noticed all these cavities, or broken fillings AND they hygenist did such a poor job of cleaning my teeth every FOUR months that I now require a deep-clean?”
He just blinked and didn’t say a word. They hygenist carried on with her high-pressure sales tactics. It was the stupidest scam a dentist has attempted to pull on me. I would have bought the whole story had I not been to the dentist in 10 years, but I knew damn well that I had been going to a good dentist. The whole “we don’t take insurance of any kind” bit tipped me off. I walked out without letting them finish the exam or anything and later found a new dentist. Who is awesomeness. She took one look at my mouth and said, “No, your gums are fine, you don’t need a deep clean. And you don’t have four new cavities. You have one tiny little pit and you have one cracked filling. Can we go ahead and do both at the same time, so you don’t have to worry about the tiny little pit?” Yes, absolutely, and one appointment later it was a done deal and I haven’t had any other dental work since.
Not all dentists are reputable, ethical, and honest. You have no way of knowing if your friend’s dentist in Florida is one of these rip off artists or if he or she actually had decay underneath his or her fillings, which would then necessitate a root canal.
Dentist here.
Filings need to be replaced when they break or get recurrent decay. There really isn’t a time frame. Well placed amalgams can easily last more than 20 years. Thirty years isn’t rare. Composite are a little more problematic, not as much evidence for their longevity as they just started being placed in back teeth about 20 years ago. They are also much more tecnique sensitive and don’t do well if they extend below the gumline.
The key to longevity isn’t just how well they are placed but also how they are maintained. In my practice I’ve placed plenty of fillings on kids for won’t brush and eat nothing but sugar and they often have recurrent decay at the next 6 month check up.
Unfortunatly dogzilla is correct there are some dentist out there that are replacing things that don’t need it. Makes it bad for the rest of us.
Generally if a filling has enough recurrent decay to need a root canal they patient will feel it or the filling will break. Not always but more often then not.
It’s possible I suppose but they claimed they went to a good dentist with a good reputation. I wonder if there filling just “leaked” and allowed further decay. One thing I wonder is how can they tell if a clear filling is leaking? with a mercury filling it would be easy I imagine.
That’s what I was going to say (not a dentist, but I’ve had a lot of fillings a long, long time). I had some mercury amalgam fillings that lasted decades - I actually got compliments on them from dentists who saw them later on. They’ve all been replaced now, either because decay got under them or because a filling next to them was getting replaced and I got tired of the “mouth full of metal” look of my molars - they’re all shiny white now (composite resin or crowns). 
Fillings don’t have a liquid center or anything. They are solid, hard. If a filling is “leaking” then it’s not a filling.
“Rid(ding) yourself of mercury” is a bad idea as already pointed out, requiring painful, expensive and unnecessary removal of fillings, loss of additional tooth structure, expense, and exposure to other filling materials which may be even more “toxic” than mercury amalgam fillings.
*"…composite resin restorations have been shown to leach between 14 and 22 separate potentially hazardous compounds, including DL-camphorquinone; 4-dimethylaminobenzoic acid ethy ester, drometrizole; 1,7,7-trimethylbicyclo[2,2,1]heptane; 2,2-dimethoxy[1,2] diphenyletanone; ethyleneglycol dimethacrylate; and triethyleneglycol dimethacrylate [3].
In a study of 35 identifiable dental resin composite monomers/additives of commercial composite resin composites (Table 1), investigators found nine severely or moderately cytotoxic components [4]. Other studies have also shown composite resin components to be cytotoxic (causing damage or destruction of cells). [5-15] Several studies have shown that dentin bonding agents and their components are mutagenic (cause mutations in new generations). [16-19] Wataha et al stated, “the components of resin composites are hazardous in that they all cause significant toxicity in direct contact with fibroblasts.”"*
Obviously you should just let your teeth rot away completely and avoid exposure to these TOXINS! Or chill a bit, recognize that toxicity is a function of dose and look into the good safety profile of both composite and amalgam fillings. And be wary of “mercury-free” dentists who want to yank out perfectly good fillings.