Updated: Jul 21
So you think you have a cavity and you're wondering which stage of the tooth decay you're in but the problem is you don't know what it looks like. Worry not because we're going to describe in detail what each stage of the cavity entails. There will also be pictures to ensure you know precisely what you have so you know what you need to do.
Large cavities and holes in teeth don't appear out of thin air because they all start off as a harmless looking white spot, which is enamel demineralization. These white spots are caused by a combination of bacteria, sugar, and an acidic oral environment.
Once the enamel begins to demineralize you're officially at the first stage of an early cavity. When left untreated it will continue to grow and progress through all of the stages of tooth decay with the last one being potentially life threatening. Here is the progression of a cavity in developmental order.
Tooth decay stages:
First Stage - White Spots
White spots appearing on your teeth signifies enamel demineralization, which is the beginning of a cavity. A cavity which is an actual hole in your tooth has not yet formed at this stage. At this part of the progression, the enamel is weakening because it is demineralizing. It is losing minerals, getting softer, getting weaker and will eventually become decayed if left unchecked.
Since a hole has not formed, this stage of tooth decay can still be referred to as a pre-cavity. The damage that is done to the enamel is still completely reversible and preventable with sufficient oral hygiene.
This is a picture of what the start of a cavity looks like, enamel demineralization:
Appearance: The white spots look like a splotch of chalky white on the surface of the tooth enamel. The color is more opaque than translucent, which makes it visually prominent since it is a stark contrast from enamel.
Symptoms: Since this is the earliest form of a cavity, there is often little to no sensitivity at all. It won't feel painful nor will you even realize it is there if you're trying to feel it by sensation. The only way that you can only tell if you have it is if you see it on your tooth.
Since white spots are the result of the enamel demineralizing, the treatment for it would be to remineralize the enamel. This involves a combination of good oral hygiene practices and the use of a toothpaste with remineralization capabilities.
Good oral hygiene. In order to prevent these lesions from progressing, you must brush for at least 2 minutes twice a day. Make sure you floss after dinner and then use a mouthwash to get rid of all food debris.
Fluoride toothpaste. A toothpaste that contains fluoride can stop and reverse cavities. It is particularly effective in treating white spot lesions. In fact, fluoride will strengthen your enamel by transforming the hydroxypatite crystals into fluorapatite. This new crystal is harder, more stable, and less soluble to acid attacks.
Hydroxyapatite toothpaste. Another toothpaste with remineralization capabilities is one with hydroxyapatite because your teeth contain the same exact mineral. It will stop and reverse cavities along with creating an additional layer of hydroxyapatite over the enamel, which serves as protection. This is an alternative for those who prefer to use a non-fluoridated toothpaste.
Minimize sugar intake. Since bacteria require sugar as a fuel to create acid to demineralize your enamel, you can slow down the progress by minimizing sugar in your diet. It would be even more effective if you eliminated sugars from your life.
Fortunately this stage of tooth decay is still reversible so it does not necessarily require intervention by your dentist. No drilling or extensive dental procedures are needed at this point in time of the caries progression because you can treat this at home.
Second Stage - Enamel Decay
White spots that are left untreated will progress into enamel decay, which is when the second stage of decay starts. This affects more than just the surface of the enamel because the cavity has started to work its way further into the tooth. The boundaries for when it can still be called enamel decay is when the cavity is in between the outer layer of enamel and before it reaches the dentin layer.
Here is a diagram showing the different layers of a human tooth:
This stage of the cavity is contained within the enamel and is still reversible because the damage is not permanent. As long as you maintain good oral hygiene, you can stop the decay because enamel is made of hydroxyapatite that can be strengthened with fluoride.
Here is a picture of what decay in the enamel looks like:
Appearance: It will look like a black spot or brown dot on your tooth. It can be located on any surface of the tooth such as the sides, top, and even in between. Depending on how far along the decay is, there may or may not be a visible hole.
Symptoms: Aside from its appearance, a cavity at this stage is typically not sensitive at all. That means you won't be able to feel it nor will you really be able to tell that you have it unless you look in the mouth. Although there are a few rare exceptions where some people are able to feel sensitivity to sweet for enamel decay.
If you're fortunate enough to catch the decay at this stage, intervention by your dentist is not needed because the cavity can still be reversed. Decay that is still in the enamel can be stopped and reversed if you maintain proper oral hygiene and use either a fluoridated toothpaste or one with hydroxyapatite.
Good oral hygiene. In order to stop these lesions from progressing, you must brush for at least 2 minutes twice a day. In fact, the more you brush the better the outcome will be. Make sure you floss before bed and then use a mouthwash to get rid of any residual plaque.
Fluoride toothpaste. A toothpaste that contains fluoride can stop and reverse cavities in the enamel. In fact, fluoride will strengthen your enamel by transforming the hydroxypatite crystals into fluorapatite which makes it harder, more stable, and less soluble to acid attacks.
Hydroxyapatite toothpaste. Another toothpaste with remineralization capabilities is hydroxyapatite because your teeth contain the same ingredient. It will stop and reverse cavities along with creating an additional layer of hydroxyapatite over the enamel, which serves as extra protection. This is an alternative for those who prefer to use a non-fluoridated toothpaste.
Minimize sugar intake. Since bacteria require sugar as a fuel to create acid to demineralize your enamel, you can slow down the progress by minimizing or even eliminating sugar in your diet.
Third Stage - Dentin Decay
The third stage of decay starts when untreated enamel decay is allowed to progress into the dentin. This marks the point of no return because once the cavity is in the dentin, it can no longer be stopped nor reversed. In fact, the decay grows exponentially faster than when it was in the enamel. You can no longer just observe and watch these lesions, they require immediate attention by your dentist.
This is what the third stage of decay in the dentin looks like:
Appearance: Once the cavity enters the dentin, the color is always some shade of brown. If it is very advanced and severe, the decay can look almost black. From the picture above you can see that the chalky white spot is the enamel demineralization but beyond that is the dentin which looks brown.
Symptoms: Some people may be able to feel sweet sensitivity for a cavity at this stage but not everyone will be able to sense it. This brings up an important point that even if you do not feel any sweet sensitivity, it does not rule out that you are cavity free. The only way to know for sure is to have your dentist take x-rays and give you a proper diagnosis.
Since this is the stage of no return, that makes the damage by the decay irreversible. This is the first stage of tooth decay that requires intervention by a dentist because you cannot treat this at home. The only way to treat it is by getting the cavity filled. The good news is that this treatment only requires a single dentist appointment.
Dental filling. You will need to make an appointment with your dentist to have the cavity removed. After it is removed, you can get a tooth filling that is usually tooth colored. Some older offices may still be using the silver fillings but the trend is towards the white ones.
After you get the cavity removed, you should aim to improve your at home oral hygiene routine so that you don't end up getting more decay at your next check up. Just because you had the cavity removed, it does not mean it can't come back. You can always get a new cavity underneath of the new filling and we call that recurrent decay. Don't let that person be you!
Fourth Stage - Pulp Decay
The fourth stage of a cavity starts once the dentin decay progresses into the pulp of the tooth. The previous stage was already irreversible so that makes the damage to the pulp permanent. Starting at this progression of decay, everything becomes a lot more serious because this is when you can start feeling a toothache. Treatment for this deep cavity also becomes more complex and more expensive so it would be in your best interest to not let it get this far.
Here is a cavity picture of decay that is into the pulp:
Appearance: A cavity that has reached the pulp is a very big lesion that typically looks black or dark brown in color. You can often see a visible cavitation or hole in the tooth and that makes it a huge food trap. You'll constantly get food stuck in the cavity and you're force to try to dig it out. You may even be able to feel the hole with your tongue.
Symptoms: This is the first stage of tooth decay where you can start feeling pain. The reason is because the pulp is filled with nerve endings and is where the tooth connects to the rest of your body. Here are some common symptoms:
Constant dull ache.
Throbbing tooth pain that comes and goes.
Extreme tooth pain that can wake you up at night.
Unbearable toothache that shoots pain up your head.
Tooth hurts to chew on.
Everyone will feel the pain in a different way but none of them are pleasant. Most people will be actively seeking out a dentist to get rid of the toothache at this point.
The cavity is too large for a simple filling to be able to fix it. Since the nerve is involved, the nerve will need to be treated and that is the specialty of the root canal specialist.
Root canal. The first step of treatment is a root canal by your dentist, which involves separating the nerve from the tooth. You will be completely numb for the procedure so you won't feel a thing despite the horror stories you may be hearing.
Core buildup. The hole that was drilled into your tooth to remove the nerve will need to be filled back in and that is what a core buildup is. It is a bonded resin that restores the tooth structure.
Dental crown. The last step is to have a crown made for your tooth, which covers and protects it 360 degrees. The reason is because when the nerve gets removed via a root canal treatment, the blood supply also gets removed along with it since they both occupy the same canal. Once the blood supply is gone, nutrients stop going to the tooth and it starts to get very brittle. That makes the tooth prone to fracture if you bite down on something hard the wrong way. The purpose of a crown is to minimize and prevent fractures after a root canal.
Treatment for decay at this stage is not basic because they are considered major dental treatments. That makes it more costly financially as well as time needed to complete all of these procedures. It may take a total of 4-5 visits to finish everything, which is a lot longer in comparison to the previous stage of decay which only requires one visit.
Fifth Stage - Tooth Abscess
Untreated pulp decay will inevitable progress to the next stage of tooth decay called a tooth abscess. This happens when the cavity obliterates the tooth nerve and travels all the way to the tip of the root where it starts to form an abscess in the bone. The abscess will start to eat through the bone and form a dark circle on the dental x-ray. It is as scary as it sounds because this is a true tooth infection.
Here is what a tooth abscess looks like on an x-ray:
Appearance: What a dental abscess looks like on an x-ray is a big dark circle surrounding the tip of the tooth root. Solid objects show up as white on the x-ray while less solid ones show up looking black. This means that the bone that is holding your tooth in is becoming less solid because the infection is eating away at the bone. You can only see this on an x-ray because you can't see it in the mouth since the infection is WITHIN the bone.
Symptoms: A tooth abscess will be painful. Swelling and a fever are not uncommon either. Most of the symptoms will be similar to pulp decay but will be a bit more severe and intense feeling.
Constant dull ache.
Throbbing tooth pain that comes and goes.
Extreme tooth pain that can wake you up at night.
Unbearable toothache that shoots pain up your head.
Tenderness and pain while chewing.
Possible fever and lymph nodes enlarging.
Since this is a more advanced cavity than pulp decay, it will also require additional treatment. Although for the most part, most of the steps remain the same as a cavity in the pulp.
Root canal medication. The root canal procedure will be started at this step to remove the infected nerve. Once your dentist is finished cleaning out the tooth, they will place an antibiotic medication inside of the tooth to help clear out the infection. Due to the size and amount of infection in the bone, this step is required to ensure that the tooth is infection free. The medication is left in the tooth for 1-3 weeks.
Root canal completion. You will return to your dentist to have the tooth cleaned out one last time and then have the root canal filling material placed.
Core buildup. Once again, a core build up is needed to repair the hole that was made from the root canal.
Crown. Your dentist will make you a porcelain crown to cover and protect the root canal treated tooth. This helps to prevent the tooth from fracturing if you bite into anything hard!
Treatment at this tooth decay stage will be costly and it will require a lot of time as well. Prepare yourself mentally as well as financially for what is to come.
Sixth Stage - Gum Boil
The next and sixth stage of tooth decay is an untreated tooth abscess is allowed to grow into a gum boil, which is a pimple on the gums. A pimple forms because the abscess in the bone has managed to through all of it and reach the surface of the gums. This is the first time where you will be able to visually see what an abscess looks like in your mouth.
This is what a gum boil, the sixth stage of tooth decay looks like in the mouth:
Appearance: It literally looks like a pimple on the gums, located by the side of your tooth. The gum boil will be a mix of red to white in color. Sometimes you can also see some white pus oozing out of it.
Symptoms: Surprisingly there is one positive for this stage of a cavity and that is, it often does not hurt. As strange as it may be, a gum boil often presents itself as a painless little pimple. The reason is because while you have a tooth abscess, a lot of the pain comes from feeling the pressure build up from all of the infection. Once the gum boil forms, it creates a path to relieve the pressure into the mouth and that allows the pain to dissipate.
You may notice that the abscess can pop and you'll find a lot of white pus coming out of it. The tooth shouldn't hurt but the gums may feel a little tender from the abscess.
Treatment for a tooth abscess at this stage is still the same as a regular dental abscess. It will require a root canal with multiple rounds of antibiotic medication. If the pimple is big enough, it may also require some physical drainage.
Root canal medication. After the root canal is started and the nerve is removed, medication will definitely need to be placed inside the tooth. In fact, you may need multiple rounds of medication to be placed and replaced until the abscess on the gum disappears.
Root canal completion. Once the pimple on the gum disappears from the medication you can finally finish up the root canal.
Drain the abscess. If the pimple does not disappear from the antibiotic root canal medication, you will need to have the pimple drained. Your dentist will pop it and scrape the inside of the gums to ensure that the infection is all gone.
Core buildup. This is the step that fills back in the hole which was created to do the root canal. It will be bonded in with the strongest bonding.
Dental crown. An all porcelain crown will be made to protect the tooth from potential fractures and cracks. It is needed because a tooth becomes weakened after a root canal.
Seventh Stage - Facial Swelling
If you ignore the abscess that is present on the gums because it is painless, it can eventually cause your face to swell up. Once your face swells from the abscess, you're officially at the seventh stage of a cavity. This is not something that you can wait to see if it will go away on its own because it will not without intervention by a dentist. This is an emergency and you should get it addressed as soon as possible.
Here is what an abscess with facial swelling looks like:
Appearance: You can't miss this stage of tooth decay because half of your face literally swells up to twice the size as the other side. The swelling can be as big as a golf ball in size. If you look in the mirror, your face will look asymmetrical and disfigured.
Symptoms: This condition is extremely painful and is the most visible stage of a tooth infection. You can not only see it but feel it as well, which makes it very palpable.
Face feels warm and tender to touch
An abscess with swelling of this size on the face will require it to be drained first before any other treatment can be done. The tooth infection has to be really bad to get to this point, there is a chance you may not be able to save the tooth, which is causing this abscess. If that is the case you will need to have the tooth removed at the same time you drain the abscess.
Incision and drainage. Your dentist will need to numb you up as best as they can and then make a cut into the abscess with a scalpel. Next they will drain the infection with various instruments as well as their fingers. Finally, it will need to be flushed out with a saline solution.
Tooth extraction. The offending tooth will most likely need to be removed because for an infection to get that bad, the tooth is usually not restorable.
Antibiotics. You will need to be on an entire course of antibiotics to help clear out the residual infection. It will also help prevent it from coming back.
Dental implant. The tooth that is removed will need to be replaced and that is usually done with a dental implant. The implant is a titanium screw that goes into the jaw to replace the missing tooth.
Here is a video showing an incision and drainage of a very bad tooth abscess:
Treatment for swelling like this must be done because if you allow it to progress, the swelling can eventually close off your airway. That will make it difficult for you to breath and that can be potentially life threatening. The swelling is full of pus and will not go away on its own so do not take that chance.
Here is a picture of swelling that was never taken care of and the patient ended up in the hospital with drains placed in their face.
Don't let that person be you. If you have an abscess get it taken care of right away!
There are multiple stages to tooth decay with each one getting progressively worst when left untreated. Cavities will not go away on their own so don't try to wait it out. Seek medical help as soon as you suspect a cavity because the earlier you can catch it, the less invasive the procedure will be and also the less costly. Its your health and your money.
Author: Written by Dr David Chen, a long island city dentist.