top of page

Demineralization of Teeth: How They Become Weakened

Updated: Jan 17

When teeth become demineralized they get weakened because the enamel is losing the tooth minerals, calcium and phosphate. If left untreated, it will develop into a cavity.

white spots - demineralized enamel
white spots - demineralized enamel

There are a plethora of causes for why they become weakened but the good news is that it is possible to reverse it with treatment. Yes, we're going to teach you how to not only prevent it but also how to remineralize all of your demineralized teeth.

Table of Contents:

What happens during demineralization of teeth?

Demineralization of teeth is a process where the enamel experiences a net loss of minerals. That is a very concerning condition because the majority of your tooth structure is made of a mineral called hydroxyapatite.

In fact, hydroxyapatite is the primary mineral which gives your teeth and bones their structural rigidity. Your teeth actually contain more of it than your bones, which makes the enamel the hardest substance in the human body.

  • Bones contain 60% hydroxyapatite by weight.

  • Enamel contains 97% while dentin has 70% by weight.

Hydroxyapatite may sound like a foreign substance but another name for it is calcium apatite. The molecular structure is Ca10(PO4)6(OH)2 and that means it is basically made of just the minerals calcium and phosphate.

If you recall when you were growing up, it was important to drink milk to get a lot of calcium so that you grow strong bones and teeth. The entire premise behind that is because the calcium is a building block for hydroxyapatite.

Demineralization mechanism of enamel

When the enamel demineralizes, the hydroxyapatite disintegrates and the minerals separate into their individual components.

  • Calcium

  • Phosphate

demineralization remineralization of teeth
Credit: Sangi Co

Example: If you consume a lot of sugar and your teeth hurt. The bacteria in the plaque covering your teeth will process it and produce lactic acid. This acid is covering the surface of your enamel and trying to dissolve it.

Hydroxyapatite may not be water soluble but it is acid soluble so in the presence of enough acid, it will dissolve. The end result is a lot of free calcium and phosphate molecules that are now floating around.

The unbound phosphates don't just float around doing nothing. It will actually combine with the acidic H+ molecules to decrease the acidity in your mouth. This is your body's way of buffering the oral environment and reducing the acidity so that more dissolution of hydroxyapatite doesn't occur.

Phosphate buffering system

The form of phosphate that gets released from the dissolved hydroxyapatite is PO43- but it can interact with the acidic H+ ions.

  1. HPO4-2 <~> PO4-3 + H+

  2. H2PO4- <~> HPO4-2 + H+

  3. H3PO4 <~> H2PO4- + H+

Essentially each phosphate can remove and buffer up to three acidic H+ ions. Getting rid of the H+ is important because that is how you make it less acidic by raising the pH.

  • pH = -log(H+)

The less hydrogens there are the less acidic, which means the pH will be higher. A higher pH is a more basic solution. We want our teeth to be in a neutral or basic environment rather than an acidic one that can demineralize our enamel.


Signs and symptoms of demineralized teeth

As scary as having your teeth become demineralized sounds, your body does give you warning signs of it happening.

  • Teeth feel hurt when eating sweets but there are no cavities

  • Sensitivity when consuming acidic foods that are sour or spicy.

  • White spots on your enamel.

  • Visible holes or pitting - visibly see damaged or missing tooth structure.

  • Toothache - pain that may be stimulated or spontaneously.

  • Surface discoloration - black or brown staining.

white spot on molar
white spot on molar

If you're experiencing any of these symptoms, you may want to explore options on how to reverse the demineralization.

What is the direct cause of demineralization of the enamel on teeth?

The direct cause of enamel demineralization is when the pH in the mouth drops below the critical pH of 5.5 which is very acidic.

Under normal conditions, the resting salivary pH is 6.2-7.6 which is close to neutral. The enamel is only acid soluble so it remains intact at a neutral pH. However if the oral environment enters an acidic range, it does have the potential to start demineralizing.

demineralized white spot on canine tooth
demineralized white spot on canine tooth

According to the Journal of the Canadian Dental Association, the pH level when the enamel starts to dissolve is around 5.5; That number is referred to as the "critical pH" level because once it goes below that, your teeth will start demineralizing.

Therefore having the pH level in the mouth below the critical level is the direct cause of the enamel dissolving.

Activities which makes the mouth acidic

There are too many things to list which can bring your mouth into the acidic range. However the vast majority of how it happens is usually through the foods and drinks that we consume.

  • Acidic salad dressings

  • Sour foods like lemons or limes

  • Spicy foods like ghost peppers or carolina reapers

  • Sweets - cakes, cookies, extra sugar in coffee

If you're ever unsure if the food that you eat can potentially damage your enamel, just look up the pH level. As an example, a can of coke is around a pH of 2.6-2.7

It is not healthy for your enamel if you simply leave these acid residues on your teeth after your meal. You should rinse your mouth out really well with water and then wait an hour before you brush your teeth.

You don't want to brush immediately because you may be rubbing the acid straight into the enamel. Rinse out first to help wash away some of the acid and then wait for the mouth to buffer it prior to brushing.


Demineralized teeth treatment

Despite demineralization taking minerals away from your teeth, there is an opposite process called remineralization. When your teeth remineralize, minerals get added back into your dentition. Therefore the remineralization process is the treatment for demineralized teeth.

demineralization remineralization of enamel-plaque-saliva interface
Credit: Adam Hellen

Remineralizing the teeth is not a one and done deal. It is a continuous process that requires cumulative effort over a long period of time. You must do all of these activities if you want to repair your teeth.

  • Prevent your mouth from entering the acidic zone.

  • Use a remineralizing toothpaste.

  • Consume enough minerals to strengthen and repair your teeth.

Stay away from acids

The enamel will start to demineralize if the mouth drops below the critical pH level. However, the reverse is also true in that your teeth will start to remineralize if the pH remains above the critical pH level.

It is actually a natural process that occurs where the minerals in your saliva will get reincorporated back into the teeth. This only occurs if you're able to keep your mouth out of the acidic range.

Basically what you need to do is to avoid an acidic diet whenever possible. Don't eat too many sweets, spicy foods, sour foods, or drinks.

If you are unable to avoid them or minimize their intake, you should try your best to maintain impeccable oral hygiene. Rinse your mouth out after every acidic meal. Then do your best to brush your teeth about an hour after your meal.

Remineralize your teeth with toothpaste

Your mouth will naturally remineralize if you keep the pH around neutral or even basic. However you can help speed up the progress if you use a toothpaste that is capable of remineralizing the teeth.

Sensodyne pronamel intensive enamel repair vs mineral boost toothpaste
fluoride toothpaste

There are two toothpaste ingredients which are capable of remineralizing the enamel and they are fluoride and nano-hydroxyapatite. If you brush with it twice a day, you will improve your chances of repairing the teeth.

How fluoride helps

Fluoride enhances remineralization because it gets readily taken in by demineralized tooth structure. It will attract calcium and phosphates along with it. This helps the tooth to rebuild all of the lost minerals.

This new structure with fluoride incorporated is no longer pure hydroxyapatite because it has become fluorapatite. There are many inherent advantages to this transformation.

Fluoride benefits:

  • Increased resistance to acid dissolution.

  • Decreases mineral solubility.

  • Increased stability of mineral structure.

  • Promotes remineralization to reverse tooth decay.

In addition to repairing the weakened tooth, it will also form a protective barrier over the enamel. This layer is calcium fluoride-like but not quite since it has phosphates incorporated into it.

Helpful functions of this protective layer:

  • It serves as reservoir for calcium and phosphates.

  • Gets demineralized first before the enamel

How nano-hydroxyapatite works

Toothpaste with nano-hydroxyapatite also has the capability of remineralizing the enamel. One of the most important characteristics is that it is the exact same mineral that your teeth are made out of.

tooth remineralization schema with hydroxyapatite
Credit: Lijie Chen, Suma Al-Bayatee, Zohaib Khurshid, Amin Shavandi, Paul Brunton and Jithendra Ratnayake

How it helps to remineralize your teeth:

  • The nano-hydroxyapatite will fill in the voids that are left by demineralization.

  • Serves as a reservoir for calcium and phosphate.

  • Forms a protective sacrificial layer over the enamel. If it dissolves, it provides an additional source of calcium and phosphate.

Healthy diet full of minerals

In order for your teeth to remineralize, it will need sufficient minerals to repair the teeth. Since the primary minerals in enamel are calcium and phosphate, you would need to consume a diet that has enough of it.

Sources of calcium in foods:

  • Dairy - milk, fortified plants milk, cheese, and yogurt

  • Tofu

  • Canned sardines, salmon with bones

  • Leafy greens (collards, mustards, turnip, kale, bok choy, spinach)

Food sources for phosphorus:

  • Dairy - milk, yogurt, and cheese

  • Salmon, beef, poultry, pork

  • Legumes, nuts, and seeds

  • Whole wheat breads and cereal

  • Vegetables - asparagus, tomatoes, cauliflower


Demineralization of teeth is when they become weakened due to loss of minerals. This typically occurs as a result of an acid attack by bacteria in the mouth or your diet. The tooth mineral hydroxyapatite breaks down into its individual constituents, calcium and phosphate.

Fortunately the entire process can be reversed because teeth can remineralize. The opposite process can occur where the minerals calcium and phosphate get reincorporated into the tooth. However, if left demineralized the lesion can progress and you may end up needing a dental filling.



David Chen 200 x 200.jpg

About the author: Dr David Chen, DDS

Hello, I'm Dr Chen and I'm an actively practicing dentist in Long Island City, NY. I graduated from Columbia University College of Dental Medicine in 2016 but prior to going to dental school I was already working in the dental field. It's been more than a decade since I first got to know dentistry and let me tell you, time flies by quickly. Since then I've developed a fondness for writing, which is how this all got started!

Association Memberships:

Medical Disclaimer:

This blog is purely meant for information purposes and should not be used as medical advice. Each situation in your mouth is unique and complex. It is not possible to give advice nor diagnose any oral conditions based on text nor virtual consultations. The best thing to do is to go in person to see your dentist for an examination and consultation so that you can receive the best care possible.

The purpose of all of this oral health information is to encourage you to see your dentist and to inform you of what you may expect during your visit. Due to the unfortunate nature of dentistry, there isn't really any true home remedies that will get rid of dental problems. Roughly 99.99% of them require in-person intervention by a healthcare professional.

Hint: That is the reason why you can't eliminate seeing dentists in your life!

bottom of page