Does ice cream give your teeth a jolt? What about a hot cup of coffee? On a cold winter’s day, do you find yourself pressing your lips together to protect your teeth from the cold air? Does the thought of a dental hygienist using a scaler on your teeth make you shudder?
These reactions are typical for people with dental sensitivity, which might be more accurately described as hypersensitivity. Sensitivity can result from any number of triggers: most commonly cold but also heat, sugary foods, and physical stimulation. It is extremely common; some studies suggest that more than half of all people experience it. But just because it is common does not mean it should be accepted as a fact of life. However mild or severe, whatever brings it on, dental sensitivity can now be relieved through a variety of treatments. This article gives an overview of what exactly sensitivity is and what you can do about it.
What causes sensitivity?
A short anatomy lesson will help explain how teeth become sensitive, and how both over-the-counter and professional products work to stop the sensitivity.
There are two main parts to each tooth (plus the center, where the main nerve and blood supply are located). The first part of the tooth — the crown — is the visible part, the part that’s used for chewing. The crown is covered by a very hard outer shell called enamel. A bacterial infection or acidic foods can dissolve the enamel, creating tiny holes that can get bigger and lead to the formation of what is commonly called a cavity. If left untreated, a cavity can continue to enlarge until the bacteria and acid reach the nerve and blood supply of the tooth, causing pain. This type of pain is very different from normal sensitivity: It typically hurts more, and its underlying causes are different. If you have pain caused by a cavity, you’ll need to see a dentist to have the decayed material removed and replaced with a filling material.
The second part of the tooth is the root. The root extends into the bone of the jaw and keeps the tooth firmly in place. The root consists of a material called dentin. At first glance dentin looks solid, but it’s really filled with tiny tubes, called tubules, that connect the outside of the root to the nerve center of the tooth. When part of the root becomes exposed — usually where it meets the crown of the tooth — the tubules provide a direct channel to the nerve of the tooth, leading to sensitivity. Exposed tubules eventually grow closed as the tooth adapts to this exposure, but for most of us this natural process is too slow. We need relief now!
Another reason that a tooth may be sensitive is if it is cracked. This can happen as a result of an injury (such as getting hit in the face) or because a large filling expands and creates a fracture. If the sensitivity products described below don’t give relief, a dentist should be consulted; very often, he will find a crack, and the tooth will need a crown.
One major culprit in root exposure is overly aggressive or abrasive toothbrushing. If you experience sensitivity, a good way to start addressing the problem is to use a soft-bristled toothbrush and to apply only light pressure when brushing. Using a less abrasive toothpaste can also help. Since it’s nearly impossible to figure out on your own which toothpastes are less abrasive, ask a dental professional to recommend a good, gentle toothpaste.
When brushing, use a very small amount of toothpaste; a drop the size of a pea is all you need. If you always start brushing in the same area of your mouth, switch the starting place periodically — having the bulk of toothpaste applied to the same few teeth every time can lead to abrasion. This effect is often compounded by the fact that the bristles of toothbrushes are stiffest and most irritating at the beginning of brushing.
Some over-the-counter tooth-whitening products contain ingredients that can set off sensitivity. Whitening products, even those applied in the dentist’s office, dry out the teeth. Over the first few days after whitening, the teeth rehydrate and the sensitivity tends to go away on its own. Using a sensitivity-reducing toothpaste for a few weeks before whitening can help prevent the problem.
When deciding on an over-the-counter whitening product, look for one with a high concentration of hydrogen peroxide. These products are more effective at lightening tooth color and less likely to cause sensitivity. Also look for one with no acidic ingredients (such as citric or malic acid), since these can damage the enamel of your teeth. A dental professional may be able to help you select a safe and nonirritating whitening product.
Help in the dentist’s chair
When you go in for professional dental care, let your care provider know that your teeth are sensitive to cold foods or liquids, or whatever the trigger may be. There is now an array of products that can make you more comfortable both during dental treatments and outside the dentist’s office.
The products that tend to work best contain a form of calcium phosphate, a group of compounds that make up tooth enamel. These products are buffed onto the teeth with the same kind of polisher normally used to polish your teeth at the end of a routine cleaning. The calcium phosphate particles get pushed into the exposed tubules for almost instant relief of sensitivity before any dental procedure. This can mean an end to the discomfort caused by the scaling, rinsing, and polishing that happen during professional cleanings.
Another way that sensitivity-relief treatments can be applied is by using an air polisher. Air polishers have been in use since the 1970’s but have recently seen an increase in popularity. In their normal use, a mix of air, water, and sodium bicarbonate is sprayed at high pressure onto the teeth to remove plaque and stains. This is especially effective when preparing a tooth for a sealant. For treatment of sensitivity, however, a calcium phosphate powder can be used to instantly plug the open tubules that cause the problem. This delivers relief so quickly that most people are not even bothered by the air polishing itself.
Fluoride — the old standard of anticavity treatments, both in the dentist’s office and in toothpaste — can also be used to treat sensitivity. New fluoride varnishes offer a highly concentrated form of fluoride that is applied directly to sensitive areas by a dental professional; the varnish hardens and remains for several hours. While this treatment tends not to give relief as quickly or surely as calcium phosphate-based treatments, it may be worth a try for some people. Both treatments last for about six months.
Some dental practices charge extra for fluoride- or calcium phosphate-based sensitivity treatments given during regular cleaning; others do not. Since these treatments can give relief for many months, it may be worth it to pay a bit extra to receive them. For nearly everyone, these simple procedures relieve sensitivity at least long enough to let them relax during their dental appointment.
When calcium phosphate or targeted fluoride treatments are not effective, applying what is known as a resin barrier may do the trick. Just as sealants are often applied to the biting surfaces of molars to protect against cavities, a barrier can be applied to the exposed root of affected teeth to guard against sensitivity. This procedure is relatively simple: First, the exposed root is cleaned of any stains or debris. Next the resin is applied in a thin, clear liquid coat. The resin is then cured with a blue light, just like when sealants are applied to teeth. Although these barriers are intended to last for six months, many people find that they remain effective for much longer.
Another material, called a glass ionomer, may also be a good choice for some people. For those who cannot or will not brush a certain area of their teeth (for instance, the last molar), a glass ionomer can protect entire teeth from decay. This can be particularly useful for older adults and others who require assistance brushing their teeth.
Periodontal pain management
Teeth are, of course, not the only structures in the mouth that may be sensitive to certain procedures — gums and surrounding tissue can be, too. This is especially true if you are being treated for periodontal problems (those affecting the tissue surrounding the teeth). But thanks to some newer treatment methods and devices, periodontal treatments can be more comfortable than ever before.
Periodontal treatment often involves removing bacterial biofilm from pockets of infected tissue. When tissue is being manipulated to accomplish this, sometimes only a topical anesthetic is used. Often this comes in the form of a benzocaine liquid that is applied to the affected area. This form of anesthetic is also often used to help desensitize the throat for people who gag when dental x-rays are taken. Topical anesthetics can be hit-or-miss, so if you still experience discomfort during a procedure, alert your care provider. There may be another topical or injectable option available.
A topical anesthetic is also used before injection of a local anesthetic for dental procedures that require deeper numbing. After asking what flavor you’d like, the dental assistant will put a dab of gel on a cotton-tipped applicator and place it on the area of the injection for a minute or so.
A new device that was introduced in the summer of 2010 is proving to be an attractive alternative to topical anesthetics before injections. The device delivers pulsed vibration to the injection site (somewhat similar to the dentist manually jiggling your lip before an injection). The vibration confuses the nerves and blocks the sensation of pain while an injection is delivered. The vibration also helps disperse the injected liquid to get a better effect from the anesthetic. Doctors are also using this technique, called vibration analgesia, for injections of cosmetic treatments such as Botox.
Home care products
Over-the-counter products for sensitivity can work if given enough time; most should achieve their desired effect in about a month. The most common active ingredient in these items — mostly sensitivity toothpastes — is potassium nitrate. Potassium nitrate changes the chemistry of nerve fibers that are activated through exposed tubules. Over time the nerve fibers shrink, and the sensitivity won’t return.
One calcium phosphate product used in the dentist’s office is also available in over-the-counter pastes. The ingredient is called NovaMin, and it can be found in Burt’s Bees, SootheRx, and Dr. Collins Restore toothpastes. Some other toothpastes, such as Spry, also contain a calcium derivative that may help treat sensitivity. Check the label of sensitivity products to see if they contain a calcium compound.
Products that contain calcium phosphate or a similar ingredient for sensitivity can be purchased from many dental practices, as well. Buying from the dentist’s office has some practical benefits: Your dentist or hygienist can give you advice about how to use the product, and if it’s not working or you have any questions, you’ll have someone you can easily contact. (To learn more about who’s who at the dentist’s office, click here.)
Getting the help you need
People with diabetes are more susceptible to many dental problems, including cavities, fungal infections, and periodontal disease. It’s especially important, if you have diabetes, to practice good dental hygiene at home and to get professional dental cleanings regularly — both of which may be unpleasant and therefore neglected if you experience sensitivity. Any sensitivity that keeps you from brushing, flossing, using mouthwash, or visiting the dentist is cause for action.
The good news is that advances in sensitivity relief have made it possible to practice and experience dental care in comfort. Go online, go to the drugstore, or call or visit your dentist’s office to investigate your options — and don’t be afraid to ask about the treatments described in this article. It may take some persistence — and possibly more than one treatment — but once you have effective relief from sensitivity, you’ll be glad you made the effort.