Why are our teeth sensitive?

Have you ever experienced that your teeth get sore after being exposed to cold, hot, or sweets? If yes, this is probably a sign of cervical hypersensitivity. In adulthood, teeth often get sensitive after the consumption of cold, hot or sweet food or drinks. The pain caused by cervical hypersensitivity is not permanent; it is mostly occasional but can become very disturbing especially after acidy foods or drinks.

Cervical hypersensitivity or dentine sensitivity is characterised by temporal but penetrating pain caused by the stimuli described above or by simply breathing in. Usually it develops after gingival recession. The healthy gum (together with the underlying connective and bone tissues) covers the outer surface of the roots, to protect the underlying cement and dentine from the external stimuli in the oral cavity. Following gingival recession, the root surfaces that are less isolated will remain uncovered and the free dentinal tubules lead stimuli inside the teeth where they cause pain.

What is cervical hypersensitivity?

When the teeth are healthy, de so called dentine is covered and protected by enamel on the crown, and with cement on the root. Due to enamel abrasion, the much softer cement and dentine may become unprotected. This phenomenon is often caused by too intense brushing with a hard brush, and wrong brushing technique (horizontal brushing). According to the newest theories however, it only an additional charge on top of the pressure caused by the clenching of jaw and by the grinding of the teeth. Inside the dentine there are many microscopic canals that are open on the surface of the dentine and lead to the nerves inside the teeth. This is why the cold and hot stimuli, sweets, or even the touch of the toothbrush can irritate the receptors inside the teeth through these dentine tubules, triggering the sensation of pain.

How does tooth neck sensitivity develop?

According to the latest modern theories, the tooth neck pain is not caused by single effect, and in most cases patients are unable to help the situation. As we mentioned before, dentine sensitivity is characterised by a sudden, penetrating pain after hot or cold food, drinks or sweets. This phenomenon develops through the microscopic dentine tubules that are left free. The main causes are:

1. Night  teeth grinding with regular clenching of jaw
2. Wrong brushing technique, brushing too hard
3. Brushing with a toothpaste containing high level of abrasives
4. Consumption of too much acidy food and drinks (fruit, red wine etc.)

Even if the root became exposed, a dentist is not necessarily needed. Depending on how sensitive the teeth are, the complaint may be soothed with toothpastes, dental gels, or brushing. A tooth neck filling is only recommended in case of severe lack of aesthetical function, sensitivity or cavities developing on this dental neck damage. In the latter case, however a dental treatment is necessary. By enamel abrasion and receding gum the dentin is exposed and became less resistant than the enamel covering the crown. Dentin contains less minerals then enamel, and is less solid, so bacterial plaque causes decay on it more easily. The surface of abrasions, mostly caused by wrong brushing technique, surprisingly enough for some reason can have a polished and hardened surface, and we find less decay in case of these. In order to find the right treatment, please ask your dentist for advice.

Preventing cervical hypersensitivity

Tooth neck sensitivity can be avoided, if the cervical abrasion and receding gums are prevented. Usually, the right oral hygiene helps in preventing dental neck sensitivity. We recommend you to ask your dentist about aids to avoid night teeth grinding. Elimination of the excessive charges can be beneficial for your teeth, and it decreases the harmful effects of the wrong brushing technique. With the well known oscillating-rotating electric toothbrush we can remove film much more effectively than with the regular one, and we do not cause unnecessary pressure on the dental neck tissues. We have to pay attention not to push the toothbrush too hard.

It is very important to brush twice a day at least for two minutes with a soft toothbrush of good quality. Ask your dentist which brushing technique he recommends. After acidy food and drinks –it may sound strange- do NOT brush your teeth for at least an hour, but drink mineral water or chew on gums. This way the surface layers softened by acids get stronger again, so the brushing will cause less damage on the tooth neck.

If the gum recedes, tooth neck sensitivity may develop. It commonly occurs together with periodontal disease, because the inflamed gum recedes easily. If the gum recedes, the surface of the root, normally covered with the bone-like dentin, becomes exposed. This is an irreversible and permanent condition, even if it is not accompanied with cervical hypersensitivity. If the tooth neck is uncovered, it is very important to maintain a good oral hygiene, because at those areas tooth neck cavities may develop easily.

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