Archive for the ‘Science’ Tag
It has happened to everyone: you take a sip of ice cold tea or lemonade and your teeth give you a mild electric shock, making you take a small gasp from the suddenness of the pain. It ranges from mild and occasional, to daily and severe: it is tooth sensitivity. Tooth sensitivity is one of the most common complaints from patients, effecting almost 40 million Americans from one degree or another. We will be exploring the Why and How of Tooth Sensitivity in our Dental Bite.
The Anatomy of Tooth Sensitivity
The tooth structure is made of several layers: enamel, dentin, pulp, nerves & blood vessels. Within the dentin layer are tiny tubes that carry fluid between the enamel and the pulp. Sensitivity is often triggered when the fluid is exposed to extreme temperatures or other stimuli and the impulse is transmitted through the tubes to the nerves within the pulp. The stimulation of the nerves is what most people characterize as a sensitivity reaction when they drink something hot or cold, eat sweet things, or even breathe in cold air.
What are the causes?
Tooth sensitivity can be a symptom of a larger problem which is why it is so important that you keep your doctor informed of when you have sensitivity and what it feels like.
Sensitivity can be caused by enamel erosion which exposes the dentin to more stimuli. Enamel erosion is often due to brushing too hard or certain eating and drinking habits like excessive consumption of acid-containing foods. If you can’t start your day without eating a whole lemon, you might begin to experience sensitivity over time as the citric acid wears down your enamel exposing the dentin layer. Grinding your teeth can also wear down your enamel exposing the dentin.
Another cause of sensitivity could be gingival recession or tooth decay near the gingiva. Enamel thins as it meets the gingiva and then transitions into cementum (a hard substance that covers the tooth root in a very thin layer). If tooth decay begins along the gingiva of the tooth, there is less enamel protecting the dentin and pulp from being exposed to the bacteria and stimuli. Recession of the gingiva exposes the tooth roots leaving them more vulnerable to hot and cold stimulation. Recession can sometimes be caused by improper brushing practices and gum disease.
Cracked teeth often have sensitivity as a symptom. The cracks allow bacteria from plaque to enter into the inner layers of the tooth causing sensitivity and pain. Bacteria from plaque can effect healthy teeth as well. If you have plaque build-up on exposed root surfaces, this can cause sensitivity.
Some products such as teeth whitening solutions, and some mouthwashes can be a contributing factor to tooth sensitivity. Teeth whitening solutions are designed to penetrate into the enamel layer to whiten stains under the surface. Some people feel “zinging” sensations and sensitivity discomfort after using in-office or at-home whitening products. Certain mouthwashes contain acids that after long-term use, can heighten sensitivity as the dentin of the tooth is repeatedly exposed to the solution. There are acid neutral mouthwashes available to help alleviate this problem.
Abrasive toothpastes can also be a culprit in tooth sensitivity. The abrasive materials found in some toothpastes that are effective in removing plaque and whitening teeth can sometimes wear down tooth enamel. The effect is similar to wind and sand erosion on rocks but on a micro scale.
So now we know Why and How tooth sensitivity can occur, we will address what you and your dentist can do about it on our next Dental Bite.