Tag Archives: tooth decay

Credit: Wikimedia Commons.

What causes cavities and how to spot tooth decay

Credit: Wikimedia Commons.

Credit: Wikimedia Commons.

A cavity is basically a hole in the tooth. Cavities, also called caries or tooth decay, constitute the second most common health disorder in the western world and a common cause of tooth loss in young people around the world. Cavities start small and gradually become bigger when they’re left untreated.

People who are at the highest risk of developing cavities include low-income families, seniors, people who drink non-fluoridated water, people undergoing radiotherapy, diabetes patients, smokers, alcohol and drug users, and people who consume large amounts of sugary drinks.

What causes cavities

According to a recent National Institutes of Health (NIH) estimate, 90% of cells in the human body are bacterial, fungal, or otherwise non-human. The good news is that most of these bacteria are harmless, and some are even beneficial. The bad news is that some cause all sorts of health problems, including oral diseases like cavities and periodontal disease. These bacteria are incredibly tiny, measuring only 1/500th of a human hair in width but what they lack in size, they make up for in numbers. By one estimate, there are at least 300 different species of bacteria living inside your mouth, totaling more than a billion at any given time.

When you’re having lunch or dinner, it’s not just you that’s feeding. All that bacteria inside your mouth is having a picnic too, munching on the sugars in the foods and drinks that we consume. But what goes in, must come out. After they’ve had their snack, the bacteria will excrete waste in the form of a biofilm that your dentist calls dental plaque. If plaque stays on the teeth for more than a few days, it hardens and becomes a substance called tartar.

The plaque is what allows the microorganisms to stay on your teeth for longer, until they make acids, which wear down the tooth enamel. After the enamel is worn out, the acid reaches the next layer of the tooth, called dentin, which is softer and far more susceptible to acid than enamel. Finally, the bacteria and their acid reach the pulp. This is what eventually will get you cavities. The bacteria in the plaque will also attack the gums, causing gingivitis. If left untreated, gingivitis can evolve into periodontitis, a far more serious condition where there is bone and tissue loss around the teeth.

Besides sugar, other foods that cause the bacteria in your mouth to produce acids are starches — such as bread, crackers, and cereal.

What’s more, the bacteria that cause cavities are spreadable. Yes, tooth decay is actually an infectious disease and according to a study published in the journal Microbiome, an otherwise innocent ten-second French kiss can spread 80 million bacteria between mouths!

Cavities are most commonly found where plaque forms the most easily, such as on the molars, between teeth, near the gum line, and at the edges of fillings.

What do cavities look like

More than nine out of 10 American adults have cavities, according to the National Center for Health Statistics (NCHS), and more than a quarter of American adults have untreated tooth decay.

It’s extremely important that you visit a dentist regularly have radiographs of your teeth. Because early cavities don’t pose symptoms, you might not realize you have tooth decay until it may be too late, i.e. the cavity gets too big. Some signs that you may have cavities are discolored spots on the tooth and sensitivity to cold.

In the later stages of a cavity, the pulp, which is the nerve, is visible. This makes the tooth sensible to heat, cold, sweets, and drinks. If the decay progresses long enough, parts of the tooth may fall off and the tooth may become highly sensitive to pressure. Bad breath and bad taste in the mouth are also symptoms of late cavities.

The three main types of cavities

Credit: AllizHealth.

Root cavities

Root cavities are most commonly found in older adults, who are more likely to have receding gums and other gum disorders. Receding gums expose the roots of the teeth, which become vulnerable to tooth decay now that there’s no more hard enamel to shelter them. To treat a root cavity, the decay is first removed and the hole in the tooth is plugged with a filling or crown. In extreme cases when the decay has spread to the pulp, root canal treatment is advised. A root cavity needs to be fixed as soon as it’s detected because the damage spreads quicker than in other areas of the tooth where the enamel is tough.

Pit and fissure cavities

Pit and fissure cavities appear on the chewing surfaces of teeth, most commonly on the back teeth. Most often, this type of decay is due to inconsistent and careless oral hygiene habits. This is a very common type of cavity because it’s easy for food particles and plaque to get stuck in the grooves and crevices present on the top of the teeth. If detected early, pit and fissure cavities can be treated with a good fluoride toothpaste. However, if the decay reaches the dentin, the cavity needs to be removed and the tooth repaired with fillings, composites, or crowns.

Smooth-surface cavities

Smooth-surface cavities appear on the flat exterior surface of teeth and are most commonly found on the teeth at the sides of the mouth. They occur when people do no brush correctly or regularly. These are the slowest-growing cavities and also the least common. Because this type of decay grows slowly, it’s also the easiest for a dentist to treat. Some may not need filling at all and can instead be fixed with fluoride treatments like toothpaste, gels, varnishes, or fluoride-enriched water.

How to prevent cavities

In order to keep oral bacteria in check, we need to manage them through proper oral hygiene, healthy diet, and regular dental checkups.

[panel style=”panel-info” title=”How to brush your teeth” footer=”Brushing technique recommended by the American Dental Association. “]

  • Place your toothbrush at a 45-degree angle to the gums.
  • Gently move the brush back and forth in short (tooth-wide) strokes.
  • Brush the outer surfaces, the inner surfaces, and the chewing surfaces of the teeth.
  • To clean the inside surfaces of the front teeth, tilt the brush vertically and make several up-and-down strokes.


Brushing after meals, using antimicrobial mouthwash, and flossing helps to keep these disease-causing bacteria from reproducing in your mouth, and from causing tooth decay. The American Dental Association (ADA) recommends you:

  • Brush your teeth twice a day with a soft-bristled brush. The size and shape of your brush should fit your mouth allowing you to reach all areas easily.
  • Replace your toothbrush every three or four months, or sooner if the bristles are frayed. A worn toothbrush won’t do a good job of cleaning your teeth.
  • Make sure to use an ADA-accepted fluoride toothpaste.

Credit: AllizHealth.

Fluoride mouth rinses also help reduce and prevent tooth decay; but you should always talk to your dentist about any new products you are interested in trying, because not everyone should use a fluoride mouth rinse.

Because there is little scientific evidence that suggests flossing keeps teeth and gums healthy, the Department of Health and Human Services has dropped their recommendation to floss daily. Many dental practitioners still advise patients floss their teeth daily, nevertheless.

In terms of diet, minimizing sugary and starchy food are important for keeping bacteria at bay.

So, how long has it been since your last checkup?


14,000-year-old molar gives us oldest proof of dentistry, and will make you love your dentist’s drill

Just as today — or a little less often, as we tend to abuse our teeth quite a bit nowadyas – early humans had to deal with cavities. An infected 14,000 year old molar may give us a glimpse into how they treated such afflictions, and is the oldest known evidence of dentistry.

You won’t find any fancy anesthetics or sterile, steel tools here — the procedures were performed with sharp, hand-crafted stone tools in a rudimentary but effective fashion.

The study, published in the journal Scientific Reports, analyzed a molar from a well-preserved 25-year-old male skeleton, whose remains were first discovered in a rock shelter in Belluno, Italy, in 1988. Researchers found evidence that the molar had been infected and was partially treated with sharp, flint tools.

“The treatment went unnoticed for all these years. The cavity was described as a simple carious lesion,” lead researcher Stefano Benazzi from the University of Bologna told Discovery News.

(A) Occlusal view of the RM3. (B) Detailed view of the large occlusal cavity with the four carious lesions and the chipping area on the mesial wall. Section A-A is directed mesio-distally, passing through the larger carious lesion. (C) MicroCT slice of the Villabruna RM3 in correspondence with section A-A.
Image via Nature

“The treatment went unnoticed for all these years. The cavity was described as a simple carious lesion,” lead researcher Stefano Benazzi from the University of Bologna told Discovery News.

Researchers looked at the molar under an electron microscope and found chippings and striations, suggesting intentional removal of material from the tooth using sharp tools. They then attempted to replicate the findings using materials that early humans had access too: wood, bone, and stone.

The tests confirmed that the striations found on the infected tooth were a result of scratching and chipping, with flint producing results most similar to those found on the molar. Researchers also note that the painful procedure occurred while the individual was alive.

“The discovery suggests, moreover, that in the Upper Palaeolithic era, humans were aware of the damaging effects of cavity infections and of the necessity of treating them, using stone instruments to remove the infected material and to clean out the cavity,” Benazzi told an Italian newspaper, Il Resto del Carlino, The Telegraph reports.

The ancient tooth represents “the oldest archaeological evidence of” dentistry, the study notes.

It predates the next oldest-known evidence of a dental procedure by 5,000 years. Researchers suggest the findings may show how early humans adapted the toothpicking technique to early forms of dentistry that included scratching cavities using microlithic points.


Nanotech toothbrush means you never need toothpaste again

It’s common sense – in order to brush your teeth, you need water, a toothbrush, and toothpaste. Well, a company from Japan wants to change all that: they’ve developed a nanotechnology toothbrush that basically eliminates the need for toothpaste.


The secret is that the brush is coated in nanosized mineral ions which move in the water, removing stains and enveloping teeth in a protective sheet. When you brush, the minerals pass on from the bristles to your teeth, where they stick; they also make your teeth hydrophilic, which ensures that the surface is much smoother. If you brush properly (not overly hard), the brush will last for about a month.

Designed by Japanese designer Kosho Ueshima of The Industrial Design Studio, the toothbrush is named Misoka, and is also quite attractive.

“When considering how best to convey these ground-breaking capabilities of the MISOKA toothbrush to the world, we reached the conclusion that the toothbrush should embody the concept of water itself. Given the complex world we live in that constantly bombards us with information that gets into our heads whether we like it or not, we believe it is important, when a new product appears with ground-breaking capabilities, to present it to the world in a simple way with a greater degree of purity. But at the same time, this must also express the attractions of the product itself.”

Well, really though, that’s just a way that saying if something works great, it should look great – and it does, don’t get me wrong. The technology hasn’t been officially presented – it will be presented at the 2015 Milan Design Week.

So, would you use this nanotechnology toothbrush?

2.4 Billion People Have Untreated Tooth Decay

Dental health is still a generally neglected issue throughout the world – most people just delay their dental problem or simply ignore them until they become unbearable. Although it’s pretty simple to have a correct dental hygiene, most people simply don’t care enough about this, and as a result, almost 2 and a half billion people suffer from untreated tooth decay.

Disability-adjusted life year for dental caries per 100,000 inhabitants in 2004. This study pretty much confirmed the findings from that year. Image via Wiki Commons.

Dental cavities, also known as tooth decay represent the breakdown of teeth due to the activities of bacteria. The bacteria break down the hard tissues of the teeth (enamel, dentin and cementum) by making acid from food debris on the tooth surface; sugars are the preferred nutrient supply of bacteria, so the more sugar we eat, the more we feed the bacteria inside our mouth.  If mineral breakdown is greater than build up from sources such as saliva, caries results.

According to a new study conducted by the international Oral Health Research Group; 2.43 billion people (36% of the population) have dental caries in their permanent teeth. This problem is most prevalent in South America, northern Africa and the Middle East, and curiously, it is least prevalent in China. In the United States, dental caries is the most common chronic childhood disease, being at least five times more common than asthma.

Image via Web MD.

In addition to an already existing problem, the issue is constantly developing. An estimated 190 million new cases of tooth decay in adults are expected to develop every year.

“Our report is a startling reminder of the vital need to develop effective oral health promotion strategies. It is alarming to see prevention and treatment of tooth decay has been neglected at this level because if left untreated it can cause severe pain, mouth infection and it can negatively impact children’s growth,” commented the study’s lead author, Prof Wagner Marcenes, of Queen Mary University of London.

He stressed that this is an issue policy makers should deal with more carefully – untreated dental issues have significant negative consequences on the quality of life and also lead to massive financial losses in time. The study also highlighted the problem of dietary habits when it comes to dental health. Frequent snacking and the consumption of high amounts of sugary food and drinks are now more common than ever – contributing to this problem.