The dental industry uses many words that are often used interchangeably by the public, such as caries and cavities. A caries is damage to the hard surface of the tooth called the enamel, which can be reversed. A cavity is the progression of caries to a deeper layer in the tooth that needs to be cleaned and filled by the dentist if possible.

The deeper layers of the tooth are the dentine, pulp and root canal containing the nerve. It is important to reverse caries at the earliest possible stage using diagnostic techniques at the dentist such as X-rays or fluorescence imaging, then applying a fluoride varnish, fissure sealant or using other topical fluoride sources such as toothpaste regularly. 

Read on to find out simple steps you can add to your daily routine to reverse the caries you have on your teeth now and how to prevent your teeth from future damage. Are you intrigued to find out how your dentist identifies these lesions? Are you fascinated by how damage to your tooth surface can be naturally reversed? Have you ever thought about the way the food you eat helps reverse caries? Have you monitored the number of times you eat sugary foods in a day and if that is necessary? Let this article be the start to healthier gums, teeth and a more confident smile. 

Caries can be reversed by:¹

• Using fluoride toothpaste
• Drinking fluoridated water
• Having fissure sealants as a child
• Fluoride wash treatments at the dentist
• Reducing the frequency of sugary food consumption

First stage of caries formation

Many people see white specks on their teeth, which they mistake for the beginning stages of caries, but this is due to the high exposure of fluoride during permanent tooth development known as fluorosis before the age of 8.² Therefore, if white lesions are appearing after these teeth have developed in later life, these are most likely to be damage to the enamel and most likely caries. 

The initial stage of caries formation occurs due to the normal microbiota of the mouth, which contains a range of good and bad bacteria. The most common bacteria that causes caries is Streptococcus mutans, which feeds on the sugar in your mouth producing lactic acid. This disrupts the pH balance in your mouth and causes demineralisation of the enamel.

However, there is the ‘ecological plaque hypothesis’ that suggests that it is not a specific species of bacteria, but instead a shift in the favoured species of bacteria that thrive in the acidic environment.³ 

We can often feel the coating of bacteria on our teeth as a sticky film, which is composed of sugar and bacteria. We have natural minerals present in our saliva which are calcium and phosphate. However, during the night our saliva flow is reduced, which puts our teeth at risk if we do not brush off the excess sugar from our teeth.

Throughout the day the mouth is trying to find a balance between the bacteria and minerals. As bacteria release acids and eat away at our enamel, our natural minerals from saliva and fluoride from toothpaste are used to buffer its impact by replacing it.²

Debunking myths about the cause of tooth decay

A common myth is how much sugar you eat determines the extent of your caries. However, it is how many episodes of sugar exposure that is the driving factor.⁴ This can be explained by the frequency of bacterial acid attacks that occur that remove minerals from our enamel. The porosity of your enamel changes causing it to soften, allowing more damage to occur.

Treatment

Fluoride

Fluoride is key in remineralising our enamel and restoring our teeth to healthy conditions. Below are some examples of safe fluoride treatments:

Toothpaste

The therapeutic dose of fluoride is 1350-1500 parts per million, which is found in most adult toothpaste. It is important to brush your teeth and not rinse out the toothpaste afterwards, allowing it to remineralise your enamel. It is also important to incorporate flossing into your dental hygiene routine to remove bacteria from under the gum and remove plaque.

Higher-concentration fluoride toothpaste can only be prescribed by a dentist and not bought over the counter. This will be offered to those who are more vulnerable to forming dental caries.⁵ Fluoride mouthwashes can also be used as a quick mouth freshener in between meals and to reinforce the fluoride layer on your teeth.

Remember do not use a mouthwash after brushing your teeth, as toothpaste has a higher concentration of fluoride which will be washed away and it is not a replacement for toothpaste.

Fluoridated water

Fluoride is a naturally occurring mineral in water. However, 1mg of fluoride per litre of water has been shown to clinically reduce caries and this is the level of fluoride in UK tap water, so it is topped up to this level in many areas of the country. The scheme to add fluoride to water was first introduced in America in 1945 and has been rolled out in many countries including the UK since.⁶

The Drinking Water Inspectorate formed in 1990 is an official body that monitors water conditions in the UK, which means they also check that fluoride level in water is optimal and not in excess to reduce the effect of fluorosis in children’s teeth. The latest health monitoring report was in 2022 and found that 56% of hospital admissions for young children's tooth decay can be reduced by adding fluoride to water.⁷

Fissure sealants

To protect children’s teeth from caries especially after the permanent teeth have erupted, they are offered fissure sealants on the NHS.⁸ It is a plastic coating put in the dips of the molars, which are the chewing surfaces where it is hard to clean, to prevent caries formation. These produce a smooth layer making it easier for younger children to brush at the back of their mouth without leaving food debris behind in the pits of their molars. 

Fluoride varnish

Children and adults can also have a longer lasting fluoride varnish applied which is also beneficial for those who have weaker enamel or are more prone to caries. Adults are more likely to get caries after a gum recession. There was a 37% decrease in tooth decay with the application of fluoride varnishes in young children.⁹

Vegetables

Foods high in calcium like dairy and green vegetables will also help remineralise your enamel. Taking care of the pH balance in your mouth by eating foods high in probiotics will add to this protective effect. Brewed tea, coffee, meat and fish are especially high in fluoride.

Selective caries removal

Selective caries removal is the technique of using a burr to grind the tooth down to the inner layer of the tooth called the dentine and apply a biomaterial to restore the tooth. This is mainly performed for deep caries.¹⁰

Laser fluorescence detection

Traditional mirror and probe techniques and radiographs are ineffective at finding carries around braces and margins of veneers or crowns. Therefore fluorescence that detects bacterial activity helps with early diagnosis of caries. This is critical because if infection passes through facial planes the consequences can be detrimental.

They are safer than radiographs because they use non-ionising radiation so can be used many times to check the progress of the lesion. The fluorescence identifies bacterial porphyrins which are produced by bacteria during metabolic breakdown of haem.¹¹

Summary

Early detection of caries is important in both children and adults. If they are not treated early on they can lead to painful cavities that affect the nerves and gums, ultimately resulting in you needing root canal treatment. A balanced diet, drinking fluoridated tap water, brushing your teeth at least twice a day and visiting your dentist regularly are non-negotiables if you want to reverse and prevent caries formation.

It is not too late to pick up these good habits and save yourself, your partner and your children from excruciating tooth pain and gum disease. Take a moment to schedule your next dentist appointment to monitor your mouth health and ask about the available fluoride treatments that can help reverse your caries.