How does not filling a cavity lead to tooth loss?

The cavity will. Keep getting larger and larger. Eventually, the remaining tooth structure will not be large or strong enough to support a restoration (filling) and thereby determined to be non-restorable. A non-restorable tooth needs to be extracted before an infection/pain develop.
Fracture of tooth. By not filling a cavity, the cavity will get larger and the tooth becomes weaker. At some point, the cavity will reach the nerve which will cause more pain and possibly an infection, or the cavity will get large enough that the tooth fractures. If the fracture occurs along the root of the tooth then the tooth may need to be removed.
Progressing decay. It may take some time (months-years)but cavities are caused by bacteria which don't die easily. They reproduce and continue to cause probs, they will eventually get to the nerve, to the bone and destroy the structure of the tooth leaving it unrestorable.

Related Questions

I want to know that replacing resin fillings constantly year by year can lead to tooth loss or further breakage of tooth structure?

What's the problem? If you constantly need to have your fillings replaced year after year then something is wrong.I can't tell you over the internet if it's because of improper oral hygiene & diet leading to frequent cavities, poor dental treatment, having fillings done instead of crowns or what. Perhaps a combination of all of these factors. Ask your own dentist why & if unsatisfied with the answer, see another dds. Read more...
Replacing fillings. A natural tooth without decay or fillings is a very strong structure, resistant to tremendous bite forces. A compromised tooth (fillings and/or cavities) on the other hand is much more prone to fracture, so yes, the more tooth structure that is missing due to increasingly larger decay or fillings can lead to tooth loss or further breakage. A crown over the tooth will actually strengthen it. Read more...

How soon can leaving a cavity untreated lead to tooth loss?

Variable. Depends on the severity of decay, extent and your habits. If it is small it could take a couple years, if it is large it could take months. Know that most times cavities are larger than they appear. Read more...
Cavity untreated. Well that depends on the size of the cavity? It also depends of your eating habits? It also depends on how well you take care of your teeth? The short answer is very quickly! Read more...
Depends. Cavities can progress at different speeds for different people. Check with your dentist. Read more...

I have had several cavities for nearly a decade - one tooth is missing a third. Besides the discomfort/eventual tooth loss, is that dangerous?

Long term decay. The biggest danger other than losing your teeth is acute or chronic periapical infections (abcessed teeth). Having no pain does not mean that nothing is wrong. Read more...
Yup. Infections can not only spread to other parts of your body, but a rapidly expanding infection under your tongue can push your tongue back into your throat and kill you. Since you are aware of the problems you have, why are you waiting to restore the teeth? They are only getting worse and will eventually need extraction. Seek care before you have an emergency. Read more...
Absolutely. Your teeth are part of your body. Would you let your finger, foot, head, heart, brain rot away? I hope not. Would you let termites eat your house away? Would you leave a hole in your roof until it collapses destroying the rest of your house? While some cavities may seem inconsequential now, left untreated they can become infected and kill you. Read more...

What happens to a tooth with a cavity that doesn't get a filling?

Serious stuff! It will continue to decay, leaving less and less tooth structure available to repair or salvage it. You will likely need root canal therapy and\or a crown if you wait too long or if there is already extensive caries present. Even worse would be the need to have the tooth extracted if it is un-repairable. Eventually it will cause an infection that can spread to other parts of your body. Read more...
Toothache or worse. Certain bacteria in everyone's mouth digest carbohydrates and produce acids. These acids cause a loss of minerals from tooth, which softens them. This is decay. Left unchecked, these bacteria infect nerve in tooth, and can cause toothache. Tooth may break (enamel shell is brittle and depends on inner portion [dentin] for support). Pain, expensive repair, or tooth loss occurs if no treatment. Read more...

I had a filling put in on friday on a cavity is it normal for the tooth to be sensitive to cold drinks and feel a bit of pain still after filling?

Root canal hurts. The first thing your dentist needs to check is the bite. If the bite is off you will be sensitive to hot and cold and maybe have a dull ache or inflammation and bleeding around the gums. You be clenching or grinding at night that can make it worse. Read more...
Sometimes. This is a fairly common occurance...It should go away after a few days if this continues or gets worse you should talk to your dentist I have my patients place a few drops of traumeel under their tongue to he4lp healing you can get this in a health food store. Read more...
Yes. I'm sure u had a tooth colored restoration. In order for the tooth to receive the restoration, agents are place on the tooth that may result in sensitivity. It should go away so don't worry. It's normal. If it persists be sure to call ur doctor. Be well. Read more...
Sensitive filling. Yes. Prolonged sensitivity to cold is common after having work done on your teeth. If the pain persists longer than a week or increases when biting or drinking hot liquids, contact your dentist right away. It may indicate another problem. Read more...
Can be. If the filling was deep, this can be normal. Cold is so much colder than mouth temperature that it is usually the one that we feel. 'hot' is less of a change from our mouth temperature, so we usually don't notice it. If the sensitivity does not improve/go away in a few days, then call your dentist. There may be other problems. Often the bite needs to be adlusted to get you comfortable. Good luck. Read more...

If you already have a filling can you possibly have a cavity on the same tooth you have a filling?

Yes. Filling replaces the part of the tooth that was damaged (infected). It does not protect any other part of the tooth. Please have new cavity fixed ASAP, delay can only allow more tooth destruction. Also discuss with your Dentist brushing technique, floss or Water Pik use, diet, choice of toothpaste, fluoride, snack-food choices, etc. Read more...
Of course. It is possible to have another cavity because every tooth has 5 surfaces. Read more...
Absolutely. Just because a tooth is restored once does not mean it will never need another restoration. Read more...
Yes. Yes, you can still get recurrent decay around a filling or on other parts of the tooth that are susceptible bacteria and the acids found in the mouth. Read more...

How badly does cavity filling hurt on a minor cavity in a front tooth and will I look weird after?

Fillings. That are minor/small many times do not even need anesthesia. If you require anesthesia ask the doctor to use an anesthetic without Epinephrine so it will not last as long(gen an hr with this type) and though you may feel numb and weird you will not look weird. Talk to your dentist. Read more...