The 5 Stages of Tooth Decay and How To Treat Each?

Many patients assume cavities are present only when they hurt or only
when a noticeable stain is on their teeth.

This dark groove on the patient’s tooth was photographed. The decay was partially removed to showcase that it indeed spreads and is larger than visible to our eye. This is important to treat as soon as possible. After the entire cavity was removed, you can assess how much tooth structure was lost, which could have been prevented or arrested at an early stage. The final restoration seals the tooth with a tooth coloured filling.

Tooth decay is damage done to your teeth that results in cavities, abscesses and even tooth loss. Tooth decay happens when your teeth are not regularly cleaned and bacteria is allowed to build up, causing plaque that eventually hardens into tartar and is difficult to remove. When tartar protects the bacteria, it is allowed to continue damaging your teeth. 

Tooth decay happens in stages, but luckily, there are ways to treat it to keep it from proceeding. Let’s explore the various stages of tooth decay and what treatments can be used to stave off further decay development.

Stage #1 – Initial Demineralization

Demineralization refers to the erosion of the enamel coating that protects your teeth. Enamel is one of the strongest tissues in your body, but the acids in food and drink break down the minerals that make up enamel and can cause white spots on your teeth as a first sign of tooth decay.


When caught at this stage, tooth decay can be reversed by applying CTX 4 toothpaste or a prescription fluoride toothpaste to the teeth to strengthen the enamel, making it more resistant to the acids produced in plaque and bacteria in your mouth. 

Fluoride is often present in the tap water you drink, depending on your area. In Calgary, fluoride occurs naturally in our waterways but additional fluoride is not added to the water. The best way to ensure you are receiving adequate fluoride levels to protect your teeth is to see your dentist for fluoride treatments and recommendations on the best toothpaste to use that includes fluoride.

Stage #2 – Enamel Decay

If tooth decay is allowed to continue, the enamel will break down further and the white spots will start to turn brown. When tooth enamel is weakened this much, the decay will start to create little brown holes in the teeth, also known as cavities.


At the point that cavities have formed, the decay cannot be reversed and must be removed and filled by a dentist. 

When fixing a cavity with a filling, your dentist will remove the decayed portion of your tooth and replace it with a dental filling. In early stages, we may be able to remove the cavities with air abrasion, sandblasting the cavity without a drill or anesthetic.  Fillings can be made of several different materials and we can discuss with you the best option to use and how to prevent further damage and decay.

Stage #3 – Dentin Decay

Dentin is the tissue that lies under the enamel. It’s softer than enamel, which makes it more sensitive to damage from the acids in your mouth. Tooth decay proceeds at a faster rate when it reaches the dentin, which makes this stage particularly important to avoid.

Dentin also contains tubes that lead to the nerves of the tooth so when dentin is affected by tooth decay, you may begin experiencing sensitivity to hot or cold.


If decay in the dentin is found early, it can be treated with a filling. If not, a dental crown will be required to both seal and strengthen the tooth.

Much like a filling, the damaged portion of the tooth is removed and a covering is placed over the tooth to seal it. 

Stage #4 – Pulp Damage

When decay is able to progress to this stage, it reaches the pulp of the tooth. The pulp is the inner layer of your tooth that contains the nerves and blood vessels that keep the tooth healthy. 

When tissues inside your tooth become irritated and swollen, it places pressure on the nerves inside the pulp and creates pain. 


Damaged pulp must be disinfected to prevent a larger abscess and to save the tooth. This process is called a root canal, and is completed with anesthetic, so the patient has almost no discomfort. A dental crown will be recommended to strengthen and protect the tooth. 

Stage #5 – Abscess

As tooth decay advances into the pulp, bacteria is able to enter the centre of the tooth and causes an infection. Increased inflammation in the tooth can lead to a pocket of pus forming at the bottom of your tooth, called an abscess.

Tooth abscesses can cause severe pain, swelling of the gums, face or jaw, fever and swollen lymph nodes in your neck. If a tooth abscess is left untreated, the infection can spread into the bones of the jaw, head and neck so treatment is required at this stage. 


An abscessed tooth requires intervention from your dentist. It will be cleaned and a root canal will be performed to remove the infection, damaged portion of your tooth and then sealed to prevent further issues. Antibiotics are also a common treatment for the infection related to tooth abscess. 

In some cases where the tooth has been irreparably damaged, the tooth may need to be extracted. 

Prevention is the best way to ensure your teeth stay strong and healthy for a lifetime. Good oral hygiene is vital to prevent tooth decay. We recommend CTX 4 gel toothpaste twice a day followed by flossing. Seeing a dentist for regular visits ensures we prevent build up that allows damage and decay in your mouth. Many patients are surprised to find cavities can exist without any pain or discomfort. Chewing xylitol gum, limiting sweets and snacking and discussing sealants with your dentist are other great ways to help prevent tooth decay.

While tooth decay is quite serious and can cause damage to teeth such as cavities, and potentially even tooth loss, the good news is that you can treat the decay if it is caught before irreparable damage is done. 

The dentists at Ambiance Dental are the best dentists in downtown Calgary to partner with you in preventative hygiene to keep your teeth healthy and strong for years to come. Ensure you visit them regularly and address any issues that come up right away to prevent further damage from occurring. Book an appointment for a hygiene visit today!