Why overbrushing your teeth can be dangerous?

November 22, 2015


To maintain a healthy and attractive smile you need to brush and floss regularly. These routines get rid of the food particles and bacteria that lead to decay and infection. But dental experts also warn against going over-board. When it comes to brushing, you can have too much of a good thing and the result is a “toothbrush abrasion”. Instead of helping teeth, overbrushing leads to sensitivity and a receding gumline. But before getting into that we have to consider the tooth anatomy. 
 

Structure of a Normal Crown

 
Teeth have several layers, and the outermost layer (tooth enamel) is made of a hard, crystalline structure of minerals. Calcium is a central player, phosphorous and magnesium are also important. These collaborate together to form the hardest substance in the human body known as enamel. In fact, the outermost layer of teeth is 96% mineral, with only 4% water and proteins. So yes, the enamel is strong and hard, but also brittle and prone to erosion. The next layer is the dentin, another highly mineralized substance, but with a slightly different composition. The dentin is more porous. It has little tubules running from the enamel to the pulp chamber, the next layer which contains the nerves and blood supply. When the enamel breaks down it exposes the softer dentin, and causes increased sensitivity and risk of dental decay. 
 

How Does the Enamel Break Down?

 
The process of erosion is called demineralization. Because of acidic or corrosive components, the minerals of the enamel dissolve or detach from the structure. This weakens the enamel and slowly a hole or cavity develops. Overbrushing can aggravate the problem. This is especially true along a receding gumline if the dentin is already exposed. Other factors like a genetic predisposition for gum disease, bruxism (chronic grinding of teeth), or having teeth treated by braces (orthodontic treatment) might increase your risk of damage caused by overbrushing.
 

How Much is Too Much?

 
When it comes to brushing too much, there are a number of things you might be doing wrong. These include:
 
1. Brushing Too Often
Ideally your dentist wants you to brush three times a day, after every meal. At the very least professionals suggest you brush once after breakfast and once before bed. But what if you eat six small meals a day? Should you still brush after every meal and every snack and every sip of coffee? This is where misconceptions about brushing teeth start to arise. 
 
2. Brushing Too Vigorously
Many dental patients attack their teeth with their toothbrushes, thinking they are getting rid of plaque hard and fast. But being over-zealous with your toothbrush does not remove any more plaque. Matter of fact, it starts harming the gum tissue and exposes the tooth root. Here the dentin is not protected by enamel, but rather a thin layer of cementum. Excessive or improper tooth brushing is liable to abrade these substances and do permanent damage.
Right-handed patients tend to press harder when brushing the teeth on their left hand side. On the pictures you can see enamel lesions and gum recession caused by right-handed patients overbrushing their teeth.
 
3. Brushing With the Wrong Toothbrush
Plaque is fairly soft. You could remove it with a damp cloth, if that could reach all the nooks and crannies where it hides. But once plaque hardens into calculus (tartar), the only way to remove it is with professional help from a dentist or hygienist. This is why there is not any extra benefit to using a hard bristle brush. The best manufactured toothbrushes have soft or medium nylon bristles. If you were to check these out under a microscope you would see they have rounded edges, instead of flat. This cuts down on the abrasiveness while still allowing the bristles to clean along the gumline and in the crevices of teeth.
In some Muslim cultures it is highly recommended the use of a tree toothpick called miswak. It is even mentioned in their sacred book of Quran that the use of miswak 'purifies the mouth' and it is quoted by the Islamic prophet Muhammad himself. However, science has proven that the long term use of miswak can cause gum recession and abrasion lesions on the buccal surface of the teeth.
 
4. Brushing With the Wrong Toothpaste
Toothpastes contain minor abrasive substances to remove plaque and superficial stains from teeth. Under normal use, toothpaste helps clear away plaque and food particles, but leaves the enamel and dentin intact. Researchers say it would take 80 to 100 years to remove just 1mm of exposed dentin. Enamel, as a much harder substance, would remain intact. However, not all toothpastes are created equal, especially those you might make at home. Abnormal or abusive brushing with abrasive toothpastes might not have much effect on the enamel. But it could dramatically impact the soft tissue and any exposed dentin. 
 
5. Brushing Too Soon
Acid is the most harmful substance for the enamel. So if you brush right after having highly acidic foods or beverages, the enamel has not had enough time to naturally recover. It is more susceptible to damage caused by overbrushing. 
 
What is a Proper Brushing Technique?
 
Findings published in the Journal of Clinical Periodontology suggest the optimal time and pressure for an average person’s brushing routine should be two minutes and 150 grams—about the weight of an orange. Going beyond that is not any more effective, and in fact could be harming your gums and possibly your teeth. To avoid overbrushing, here is what professionals advise:
  1. Choose your tools wisely
  2. Start timing your brushings
  3. Angle your toothbrush 45 degrees to your gums
  4. Use gentle, short, circular motions
  5. Don’t squash the bristles against teeth or gums
Also, if you eat a particularly acidic meal, rinse your mouth with water or milk immediately after. Then wait about 30 minutes before brushing your teeth. 
 
If you have more questions about overbrushing, or worry you might be too diligent in your oral care, talk with your dental care provider. They can examine your mouth and teeth for signs of overbrushing and help you better manage your routines moving forward.