Are dental fillings always necessary?

No matter your age, if you’ve been to a dentist, you probably know the feeling – butterflies in your stomach as you wait for the verdict from your oral health professional. Fillings, or no fillings?

New insight into the disease of dental caries, more commonly known as tooth decay, has come to light, and the news is good.  It seems that the progression of tooth decay can not only be stopped, it can be reversed.

This is vital information when you consider that in Australia, tooth decay is the most common chronic disease.[1]  It is currently estimated that around 26% of people aged 15 and over have untreated tooth decay. 27% of people aged 5 to 10-years have untreated decay in their primary (baby) teeth, and 11% of children aged 6-14-years have untreated decay in their permanent teeth.[2]


What you need to know about tooth decay

Tooth surfaces are built of enamel, an extremely hard form of calcium-phosphate.

Tooth decay is, in fact, the loss of tooth mineral. It generally results from an imbalance of risk and protective factors.

There are two main risk factors for tooth decay – over exposure to sugar and plaque.


Sugar from foods and drinks is fermented to acid by dental plaque bacteria. The acid dissolves (demineralises) tooth surfaces and produces white-coloured lesions (white spots or patches) on the enamel surfaces of teeth. These are the signs of early stage decay. If decay persists, tooth surfaces eventually crumble and break up (like pot holes in a road) to create cavities (late stage decay).

The role of plaque in the tooth decay process is two-fold. First, plaque bacteria ferments sugar to acid. Secondly, thick plaque separates tooth surfaces from saliva, the source of tooth minerals needed for remineralisation.

There are two main protective factors against tooth decay – saliva and fluoride.


Saliva is rich in calcium and phosphate, and is the source of tooth minerals needed for remineralisation.  Saliva also has many other significant purposes, including:

  • Managing acid levels in the mouth;
  • Protecting against bacterial and fungal infections;
  • Transporting nutrients, enzymes and minerals[3].


Fluoride helps teeth in two ways. When children eat or drink fluoride in small doses, it enters the bloodstream and becomes part of their developing permanent teeth. Swallowed fluorides, like those found in water, also become part of the saliva and strengthen teeth from the outside.  Acids are less able to damage tooth enamel that is strengthened by fluoride. However, this alone is not enough to protect teeth from decay. Daily exposure to small amounts of fluoride is also necessary.  


Delivered to the outside of the teeth from fluoridated water, or from fluoride toothpaste or a professional treatment, fluoride helps to speed remineralisation. Fluoride treatments, applied in the dental clinic, also are strong enough to disrupt the production of acids by bacteria.[4]

The management of tooth decay

Previously, it was believed that caries was a rapidly progressive disease in need of “drilling and filling.”  But recent insights show that with correct treatment, not only does tooth decay not always progress, more often than not, it can stop naturally, and even regress so long as the tooth does not yet have a cavity.

The regression is due to remineralisation of the demineralised, or decayed, tooth surface. The minerals involved in the natural repair of decayed tooth surfaces come from saliva.

Remineralisation occurs naturally, but the rate of remineralisation is significantly boosted on exposure to fluoride. As well as fluoride from water and toothpaste, dentists can paint high-concentration fluoride varnish directly onto the white patches to accelerate their remineralisation.

If, and when caries goes into remission (that is, when the disease process stops), teeth can be completely remineralised and the white patches fade, and later disappear. In other cases, when caries are in remission, remineralisation may not be complete, in which case the white scars remain, or only partially fade.


How to stop, reverse and prevent tooth decay

Now that we know that fillings aren’t always inevitable, let’s talk about how to stop, reverse and prevent tooth decay.

STOP: Decreasing exposure to sugar and effectively brushing teeth using fluoride toothpaste will reduce the thickness of dental plaque, stopping decay.

REVERSE: The STOP steps allows saliva to bathe the tooth surfaces, resulting in remineralisation of the tooth (or decay reversal).

PREVENT: Restricting sugar exposure and brushing twice a day with a fluoride toothpaste will help prevent decay.  In fact, toothbrushing with a fluoride paste alone deals with a number of the risk and protective factors. It reduces plaque thickness which enables saliva to bathe the tooth surfaces, and provides fluoride to boost remineralisation.

Regular visits to your oral health professional also play an integral part in managing the risk, prevention and reversal of tooth decay.  Your oral health professional will:

  • Diagnose your risk by examining your mouth, carrying out an x-ray and interpreting the demineralised patches/shadows. This will inform the treatment plan.
  • Treatment will not only involve application of a fluoride varnish, it may also include the application of a sealant to protect the most vulnerable surfaces of the teeth. Your oral health professional will also discuss the importance of reducing sugar intake and the benefits of brushing twice daily with a fluoride toothpaste.

We can help to stop tooth decay, encourage natural tooth repair and prevent the occurance of new caries. Now that you are armed with the right information, and motivated by the fact that future fillings might be unnecessary, perhaps the butterflies in your stomach won’t be part of your next oral health examination.


Dr Wendell Evans Co-chairs the Australian Chapter of the Alliance for a Cavity Free Future (ACFF) and is a member of the ACFF Global Expert Panel.  Formerly, he was the Colgate Associate Professor at Sydney Dental School, University of Sydney.  Wendell is also a founding member of the Oral Health Advisory Panel.


[1] Australia’s Adult Oral Health Tracker: A report card on preventable oral diseases and their risk factors. Tracking progress for a healthier Australia by 2025.  Australian Dental Association and Australian Health Policy Collaboration. 2018

[2] Australian Institute of Health and Welfare 2018. Australia’s health 2018. Australia’s health series no. 16. AUS 221. Canberra: AIHW.

[3] De Almeida P. D. V., Gregio A., Machado M., De Lima A., Azevedo L. R (2008). Saliva composition and functions: a comprehensive review. J Contemp Dent Pract, 9(3), 72-80.



The Oral Health Advisory Panel (OHAP), is a group of independent healthcare professionals with the aim of raising awareness of the importance of good oral health and its impact on general wellness.  The Panel aims to take oral health beyond the dental clinic.

Follow the Oral Health Advisory Panel via twitter @OHAPanel to stay up to date with practical advice on good oral health habits.


Wendell Evans
Wendell Evans

Founding member Oral Health Advisory Panel, Sydney Dental School, Population of Oral Health, University of Sydney

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