Tooth decay: the most widespread disease in the world

tooth decay
Tooth decay is a very common and serious problem that affects millions of people around the world. It is not just a cosmetic issue. If left untreated, it can cause pain, infection, and tooth loss.

Also, When we talk about tooth decay, we're not just talking about a single cause. It's more like a perfect storm of various factors that come together to create dental problems. These factors include bacteria, your diet, your habits, and how well you take care of your oral hygiene. Together, they can spell trouble for your pearly whites.

In this blog post, we'll explore the causes of tooth decay in more detail and discuss how you can improve your oral hygiene and dietary habits to keep your teeth strong and cavity-free.

What is tooth decay?

Tooth decay is a common dental problem that happens when bacteria in your mouth produce acids that damage the hard surface of your teeth. This can lead to holes or cavities in your teeth that can cause pain, sensitivity, and infection.

Tooth decay results from the interaction of multiple factors, including:

Keyes diagram showing that tooth decay results from the interaction of multiple factors, including bacteria, sugar, teeth, and time

  • Bacteria: Bacteria play a significant role in tooth decay. Your mouth is home to various types of bacteria, including Streptococcus mutans, which feeds on the sugars and carbohydrates from the food you eat. As these bacteria consume sugars, they produce acids that can erode the protective layers of your teeth.

  • Diet: The foods and drinks you consume greatly impact your dental health. Sugary and acidic foods, such as candies, sodas, and citrus fruits, provide an ideal environment for bacteria to thrive. These foods can increase the acidity in your mouth and contribute to the breakdown of tooth enamel, making your teeth more vulnerable to decay.

  • Saliva and your teeth condition: Saliva acts as a natural defense mechanism for your teeth. It helps neutralize acids and wash away food particles, reducing the risk of tooth decay. However, certain conditions, such as dry mouth, can decrease saliva production, leaving your teeth more susceptible to decay. Additionally, if you have weakened enamel or existing dental restorations, your teeth are more prone to decay.

  • Time: Tooth decay is a gradual process that takes time to develop. When bacteria and acids are allowed to remain on your teeth for extended periods, they continue to attack the enamel, leading to the formation of cavities. Regular brushing, flossing, and dental check-ups help prevent the accumulation of harmful substances and allow for early detection and treatment of decay before it worsens.

How can tooth decay progress if left untreated?

Tooth decay doesn't go away by itself. If you don't get treatment in time, it keeps getting worse and can go deeper into the tooth, eventually reaching the sensitive nerve. Here's how decay can progress over time:

1. The early stage: Demineralization

The first stage of tooth decay is demineralization. This is when the acids in plaque, a sticky film of bacteria and food particles, start to dissolve the minerals in your enamel.

How it looks like

Demineralization appears as white rough surface lesions, also known as white spots. These are chalky surfaces that can stain over time and turn brown due to their porous nature.

Brown spot on a tooth due to the start of a tooth decay

You may not notice any symptoms, as the decay at this stage is not painful, but a dentist can detect them with an exam.

How are they treated?

The good news is that if you catch demineralization early, you can treat it without the need for a filling.
This involves improving your oral hygiene, adjusting your diet, and using remineralizing products, based on minerals like fluoride, calcium, and phosphorus.

2. The cavity stage:

If demineralization is not treated, decay can progress to the next stage and form holes or cavities in your teeth. Dentin is the softer layer of tissue under the enamel. It contains tiny tubes that connect to the nerves of your tooth. When dentin is exposed to acids, it can cause sensitivity and pain. You may feel discomfort when you eat or drink something hot, cold, sweet, or sour.

Tooth cavity stage

How are cavities treated?

The treatment of cavities depends on how severe they are.

If the cavity is small, your dentist may be able to repair it with a filling. A filling is a material that fills the hole and restores the shape and function of your tooth.

If the cavity is large, your dentist may need to use a crown. A crown is a cap that covers the entire tooth and protects it from further damage.

However, if the decay reaches the center of the tooth or the pulp, you may need a root canal treatment. A root canal treatment is a procedure that removes the infected pulp and nerves from your tooth.

Some factors that increase your risk of tooth decay:

Some of the factors that increase your chances of getting cavities are:

  • Dental crowding: When teeth are too close together, they create spaces where food and plaque can get trapped. This makes it harder to clean them properly and increases the chances of cavities forming.

  • Enamel defects: Some people have weak or thin enamel, the outer layer of the tooth that protects it from decay. This can be caused by genetics, trauma, or exposure to fluoride or other chemicals. Enamel defects make teeth more vulnerable to acid erosion and bacterial infection.

  • Certain medications: Some drugs can affect the saliva production or composition in the mouth. Saliva helps wash away food particles and neutralize acids that can damage the teeth. A dry mouth or reduced saliva flow can increase the risk of tooth decay.

  • Snacking between meals: Eating frequently throughout the day can keep the mouth in a constant state of acidity, which can weaken the enamel and promote bacterial growth. Snacking on sugary or starchy foods can also provide more fuel for the bacteria that cause cavities.

The complications of tooth decay:

In advanced stages, tooth decay can lead to serious complications, some of which can be life-threatening. Certain individuals, especially those with chronic diseases like diabetes, cardiovascular disease, and cancer, are particularly at risk. Let's take a look at some of the complications that can arise:

  • Tooth Loss: If dental abscesses are left untreated, they can spread and damage the bone that supports the tooth, leading to tooth loss.

  • Cellulitis: When the infection spreads to the surrounding soft tissues, it can cause facial cellulitis. This condition is characterized by symptoms such as pain, swelling, redness, and facial distortion.

  • Sinusitis: Infections in the upper back teeth can spread to the maxillary sinuses, resulting in sinusitis. The maxillary sinuses are bony cavities located just above the upper teeth.

  • Septicemia: If bacteria from tooth decay enter the bloodstream, it can lead to septicemia, a severe and potentially life-threatening systemic inflammatory response.

  • Endocarditis: Bacteria can travel through the bloodstream and reach vital organs, including the heart. This can result in a condition called endocarditis, which is an infection of the inner lining of the heart.
complications of tooth decay


Taking certain measures can go a long way in preventing cavities, strengthening your teeth, and preserving your smile and overall well-being. Here are some helpful tips to achieve these goals:

Oral hygiene

  • Brush your teeth at least twice a day for two minutes using a soft-bristle toothbrush. Brush vertically from the gum to the tooth to effectively remove plaque and food debris.
  • Clean between your teeth using dental floss or an interdental brush to prevent interdental cavities. These areas are hard to reach with a regular toothbrush.
  • Consider using fluoridated or other mineral-based products to strengthen enamel, reverse early lesions, and provide antibacterial benefits.


  • Reduce consumption of sweet and sour foods that can damage your enamel.
  • Choose tooth-friendly foods like yogurt, milk, cheese, nuts, or apples to end your meals. The last food you eat can impact the acidity in your mouth in the next few minutes.
  • Avoid snacking between meals to minimize acid attacks and maintain the protective role of saliva.
  • If you can't brush your teeth after a sweet meal, drink a cup of water or chew sugar-free chewing gum to clean your teeth, regulate acidity, and stimulate saliva production.

Regular visits to your dentist

Regular dental visits are essential for maintaining optimal oral health. Make it a habit to visit your dentist every six months for a check-up and professional dental cleaning. This routine allows for the removal of plaque and tartar, which are the main culprits behind tooth decay.

Apart from cleaning, these visits are crucial for identifying early lesions that may otherwise go unnoticed. It includes interdental cavities that hide between the teeth, which can sometimes only be detected through X-ray examinations.

By staying consistent with your dental check-ups, you can catch any potential issues early on and receive appropriate treatment to prevent further complications.