Causes of Cavity in Teeth – How to Prevent Tooth Decay

Even in 2020, tooth decay is still one of the most common diseases in the world.

As cavities progress, they cause damage to the tooth and if it reaches the nerve in the centre, it can result in extensive pain and infection, requiring expensive dental work or removal of the tooth.

A cavity is where the tooth enamel ( outside layer) is eaten away by bacteria that then enter the inside of the tooth and cause further damage.

The common language used to describe dental problems can often be confusing. A cavity to most people means a hole, or a void. And most of the time, teeth with decay don’t feel broken, and they are not hollow. It is only once a cavity progresses undetected for a long period of time, that tooth becomes weakened and breaks. This typically reveals a discoloured or rotten tooth that has collapsed.

In this situation, the cavity has usually been present for months or years, and the patient only becomes aware of it once it eventually crumbles. Cavities can be thought of similar to how termites work, or how a worm might burrow into an apple. There is often a small point of entry, but the real damage is going on inside.

In some scenarios, a cavity is very obvious, as the tooth surface appears discoloured, and eventually starts to break down. If this is on the front of a tooth, you may be able to see it when brushing or even just looking more closely in the mirror. Unfortunately most cavities are difficult to detect unless you are a dentist. As with most things, the best time to treat a cavity is when it is small, the damage is minimal and there is a reduced chance it requires expensive and complicated treatment. 

So the causes of a cavity in teeth are all related to bacteria. This does not mean that teeth are only ever damaged by bacteria. Teeth can become damaged by accidents, grinding, acid erosion and heavy brushing. A cavity however, is a different process. 

defense causes of cavity in teeth south brisbaneParticular types of bacteria join together to form sticky plaque. Many of them like to eat carbs, and in particular sugar. So if you feed them sugar, by consuming it yourself you make a very happy home for them, increasing their population and ability to cause harm. 

A bacterial waste product of sugar consumption is acid. Acid has the ability to break down and dissolve tooth structure. The cavity forms when the acid starts to breach the hard outer enamel layer. Once they enter the softer, inner layer of dentine the process can occur more quickly, as it effectively burrows it’s way deeper and deeper towards the nerve of the tooth. The once solid tooth becomes weak, soft and mushy and eventually the outer shell of enamel can crack and break through.

So if we know bacteria cause tooth decay when fed carbohydrates, it gives us plenty of opportunities to defend against this process.

The first is to reduce the amount of plaque present by brushing and flossing regularly. If you brush at least twice a day, and floss in the evenings you will be removing the bacteria before they have a chance to multiply. Toothpaste helps to remove plaque, and the ingredients in most toothpastes are antibacterial and have tooth strengthening properties. 

The second is to reduce the amount and frequency of carbohydrates, (especially sugar) that you consume. What is interesting is that the frequency and time that sugar spends in your mouth is more relevant than the total amount that reaches your stomach. As far as cavity causing bacteria are concerned, a supply of sugar in a person that consumes lollies or sugary mints regularly during the day is a perfect environment to cause harm. 

If you were to eat more than that same amount of sugar in a 5 minute binge, it would spend less time in the mouth and provide less opportunity to be digested by bacteria.

So binging is better than grazing as far as your dental health is concerned. Better still is that you brush your teeth, or at the very least rinse with water or chew sugar free gum after eating sweets. This is not an endorsement of high sugar intake, as we are all aware of the increased risk of diabetes and other health problems. 

Tooth enamel is the hardest substance in the body, but it is still susceptible to damage. If you want to avoid a cavity, the simplest way is to clean your teeth regularly, use a fluoride toothpaste and minimise the consumption of sugar. Early detection of tooth decay means that minimal and less expensive treatment options can be implemented and teeth have a much better prognosis. 


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