9 Common Reasons for Sensitive Teeth and Mouth

The environment within the mouth and structure of the teeth are geared to handle a range of chemical, thermal and physical insults during the course of a day. After all, the mouth is one of two main points for a range of external substances to enter the body – the other being the nose. While these areas tend to react to the entrance of any noxious substances, it should not be painful of uncomfortable if food or drinks enter the mouth just like air should not pose a problem to the nose. However, there are instances where eating regular food and drink can be a problem due to abnormal sensitivity of the teeth and mouth.

Sensitive teeth (dentinal hypersensitivity) is a common problem that is fairly well understood. It is a result of the outer enamel of the teeth being eroded. This allows for the food, drink and air to make contact with the inner sensitive tissue of the teeth known as the pulp. Sensitivity of the mouth is often as symptom of stomatitis – inflammation of the mouth lining. Similar conditions can affect the gum (gingivitis) and the bony tissue that anchors the root of the teeth (periodontitis). There are various different causes of all of these mouth, gum and tooth disorders, some of which are common everyday items and habits.

Tooth Whitening Agents

tooth color

In the search for pearly whites, there are number of different products that can be used. Some whitening agents and treatments should only be done by a dental professional. Others are available over-the-counter as teeth bleaching kits or in the form of toothpastes. While many of these products are very effective in achieving the purpose of whitening or brightening the teeth, it is undoubtedly quite harsh in nature. Peroxide is one of the common bleaching agents that are used in most tooth whitening agents. The ingredients may not only damage the hardy tooth structure, it can also irritate and even damage the inner lining of the mouth and gum thereby causing sensitivity of the teeth and mouth.

Brushing Hard and Mouthwashes

Sometimes overzealous dental hygiene can cause sensitivity of the mouth just as much as it would with the teeth. Despite the advances in toothbrush technology, the human factor is still highly individualized in determining how the teeth will be cleaned. One common problem is brushing too hard. It may be just a force of habit or in the attempt to clean the teeth as thoroughly as possible but brushing too hard erodes the outer enamel of the teeth. It can also injure the gums and mouth during  brushing. Mouthwash can be as much of a problem. Using mouthwash too frequently or opting for certain stronger varieties may also irritate the lining of the mouth and gradually erode the tooth surface.

Eating Acidic Foods


While strong acids may immediately injure the mouth and is not routinely consumed, certain foods and drinks may also be a problem despite being relatively mild acids. If consumed over long periods of time especially without good dental hygiene, these acidic foods and drinks damage the teeth and irritate the mouth. Citrus and various other fruits, cola soda, vinegary foods and alcoholic beverages are some of the problem items. Its effects are greatly reduced by consuming sufficient water, simultaneously consuming alkali food/drinks and with good dental hygiene that ensures small amounts are removed from between the teeth and in other crevices in the mouth.

Chewing Tobacco And Other Irritants

Tobacco chewing irritates, damages and erodes the mouth lining and teeth. Short term irritation may cause prominent sensitivity of the mouth and teeth but in the long term the damage is permanent. Even cigarette smoking has a similar effect although not as severe. At first the mouth becomes insensitive with constant use of the substance but eventually the damage done to the lining and teeth may expose the inner tissue to foods and drinks in the mouth thereby leading to sensitivity. Another common problem is with chewing areca nut (betel nut) and betel leaf. Both chewing habits also increase the chances of mouth sores like ulcers and even cancer.

Recent Dental Work

The mouth and teeth are overly sensitive after any dental work, be it a tooth extraction, root canal or more intensive dental surgery. However, this should resolve shortly afterwards once the tissue heals. Constant sensitivity after dental work may indicate poor workmanship on the part of the dentist. There may be exposed tissue or incomplete seals thereby allowing foods and fluids to penetrate into deeper lying tissue that is rich in nerves. Even microscopic gaps can be a problem. This can lead to sensitivity of the mouth and teeth and should be followed up with the dentist.

Infections of the Mouth and Gums

oral thrush

There are a range of infections that can affect the mouth and gums. It may even extend into the underlying bone tissue which anchors the teeth. This can lead to infectious stomatitis, gingivitis or periodontitis. It is mainly caused by bacteria and viruses. A less common infection that can also cause discomfort is oral thrush which is a candidal yeast infection of the mouth. It is more frequently seen in patients who are immune compromised, be it through HIV/AIDS, uncontrolled diabetes mellitus or with the use of chemotherapy or anti-rejection drugs after transplantation procedures. Long term and overuse of corticosteroids may also increase the risk of infections in the mouth.

HIV and STD’s of the Mouth

HIV infection and the onset of AIDS can increase the risk of oral thrush which may lead to sensitivity of the mouth and gums. However, even without oral thrush or other orodental infections, some HIV patients tend to experience mouth sensitivity as a symptom. Sexually transmitted diseases (STDs) of the mouth can also be a cause. It is often transmitted through performing oral sex but can also be spread from one partner to another through kissing. Sometimes there may be a lack of symptoms like redness, lumps or bumps in the mouth and sensitivity may be the only noticeable symptom.

Cracked and Rotten Teeth


Dental cavities, often referred to as rotten teeth, arise when bacteria are able to erode the teeth and thrive within the ‘holes’ it creates in teeth. These bacteria have a constant source of nutrition from the food that gets stuck in these cavities. It can be avoided to a large extent, but not completely, with good dental hygiene – using a toothpaste with fluoride, brushing at least twice a day, flossing and regular use of a mouth wash. Even if you practice good dental hygiene, this offers no protection against cracks in the teeth. Biting on hard nuts, chewing ice or even a blow to the mouth may cause tiny microscopic cracks that may lead to sensitivity of the teeth. It needs to be sealed by a dentist if there is no complication with an infection and the problem resolves thereafter.

Receding Gums

The roots of the teeth are rich in nerve tissue that are not as well sealed as the exposed parts of the tooth surface. Fortunately it is shielded within the gums and usually does not cause a problem. However, receding gums may expose the roots. While it does happen to some extent with age, more severe receding is seen with underlying gum and bone diseases like gingivitis and periodontitis. Both conditions are treatable and receding gums can be avoided with early diagnosis. It is therefore important to go for regular dental check ups as gingivitis and periodontitis may not cause any major symptoms at the outset but can cause severe complications as it progresses.

All pictures sourced from Wikimedia Commons.

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