Painful or sensitive teeth is called Dentine Hypersensitivity. This happens when the hard outer layer of enamel is worn away exposing the dentine, or if the gum overlying the tooth recedes to expose the dentine on the root of the tooth.
The dentine is made up of millions of small tubes running to the centre of the tooth where the nerve (of the pulp) exists. These tubes contain fluid that is still when the dentin is covered by enamel or healthy gum.
If these tubes are exposed the fluid can be disturbed by:
- Hot or cold temperatures caused by food and drinks.
- Pressure changes as you talk or brush your teeth.
- Chemical changes, again caused by food or drink.
The movement of this fluid is picked up by the nerve leading to a pain response.
This is quite common with 30% of the adult population affected by sensitivity.
The hard outer enamel may be worn away by;
- Erosion, this is the effect of acid on the teeth. The acids may be from food or drinks as well as from gastric acids in the form of heartburn or if you are repeatedly ill as in morning sickness. The acid weakens and softens the surface of the tooth allowing it to be worn away.
- Attrition, this is caused by the teeth wearing over each other. Usually, as we eat or talk the teeth rarely touch and so in normal use the teeth don’t wear away. However, if you develop a habit of either clenching your teeth or grinding them over each other (while you sleep) this can lead to the teeth wearing away.
- Abrasion, this is where to tooth is worn away by other substances either from gritty food, brushing too hard or habits like biting on pens etc. Lip and Tongue studs will also cause abrasive damage to the teeth. Not only are these unhygienic with lots of bacteria around them but it is very common to see tooth wear associated with them and so it is rare for dentists to recommend them.
It is more common for tooth wear to be caused by two if not three of these factors
How Do I Prevent Sensitivity?
Try and reduce the amount of acids in your diet and restrict them to mealtimes and no more than twice a day.
If you suffer heartburn or acid reflux form vomiting seek medical advice to see if this can be reduced.
Use a soft to medium bristle brush with a fluoride toothpaste, twice a day. If you are suffering sensitivity it is probably best to brush before meals, never directly after an acidic meal or drink, and don’t brush too hard.
If you feel you are clenching or grinding your teeth it may be worthwhile speaking to your dentist about a bite guard, when this is worn at night it protects the teeth from wearing away.
What type of foods are acidic?
Most commonly, fruit is quite acidic, apart from bananas and coconut. Grapefruit, apples, oranges, and pineapples are the most acidic. Fruit drinks (pure or diluted), sweet teas, ALL fizzy drinks, and sweets are all terrible for your teeth. Sparkling water is fine and doesn’t affect the teeth.
Fruit is part of a healthy diet and will not cause harm if it is taken 1-2 times a day as part of a meal. However, if you snack on these foods throughout the day, especially over a long period they will cause a lot of problems.
SALIVA; a protective superfluid
The saliva helps to protect the teeth in a number of ways, it is a neutral fluid so it will dilute the acids. The saliva also contains minerals that help buffer (reduce) the acidity and allow the tooth to regenerate and heal.
Saliva also contains proteins and minerals and they form a layer over the tooth called a pellicle which protects the tooth from acid damage. I sometimes feel saliva is like a liquid layer of enamel over the tooth.
When we see, smell, and eat food our saliva flow increases. This increases the tooth protection and is why we try to limit fruit and fruit juices to mealtimes only.
Some medications and conditions may lead to a dry mouth, where the salivary flow is decreased. If you feel this is the case, speak to your doctor about trying to change or alter your medication.
Your dentist can carry out tests on your saliva to check its flow rate as well as the natural buffering ability of your saliva.
We may be able to improve some problems with saliva, others we cannot change, but if we are aware of the problem we can at least make allowances and advise you on it.
How Do Toothpastes Help
Toothpaste works in two ways, it either contains a chemical that will block the nerve impulse to prevent the pain reaction or it contains minerals to block of the exposed tubules and prevent the movement of fluid in the tubules.
Sensitivity toothpaste that contains Potassium Nitrate, Potassium Citrate or Potassium Chloride is designed to block the pain signals and are often in rapid relief toothpaste. If you have a particularly sensitive tooth apply some to the area on the tip of your finger or a cotton bud and leave to soak in.
The toothpaste that physically blocks off the top of the tubules contains some form of fluoride, calcium, arginine or sodium salts. Again if you are using these use a gentle brushing motion, soft to medium bristle brushes. When you finish brushing swish the foam around all your teeth for 20 seconds, then spit the foam out but don’t rinse. This saturates the saliva in the minerals and your teeth are bathed in the minerals and allows your teeth to harden.
A newer form of toothpaste is being developed that contain either an amorphous type of calcium that is absorbed deeper into the tooth or bio-active silicates that forms a protective layer over the top of the tooth. These seem to be useful in the treatment of sensitivity.
Simple Steps to Protect Your Teeth
Your teeth are designed to protect and heal themselves. If they are exposed to acids and soften, the saliva will re-harden the tooth, toothpaste will help a bit and so we need to ensure the mouth is under repair mode more than it is under attack.
Cut down on snacking between meals, and if you do snack, avoid acidic fruit or juices. Fruit is an important part of a healthy diet and while these acidic fruits can cause erosive tooth-wear it is much less damaging if they are taken at meal times.
Cut down on fizzy drinks and fruit juices. Make fizzy drinks a very occasional special treat for kids, not an everyday drink. When fruit juices limit them to mealtimes when they are washed away and diluted with foods. If you take a drink or eat a piece of fruit, your mouth will be acidic for about 20 minutes after you finish, the tooth surface will remain soft for anything up to 2 hours. If you sip the fruit juice throughout the day or make up a bowl of fruit to nibble on your mouth remains acidic, the teeth remain dangerously soft for many hours without the chance to heal and re-harden.
Use fluoride toothpaste containing minerals that combine with elements in saliva to form a harder version of enamel that is more resistant to acid erosion. The minerals in toothpaste will also form a protective layer over the teeth. Toothpaste should contain at least 1450ppm fluoride, ask your dentist for advice on the best toothpaste for you, it is possible to have a higher strength toothpaste prescribed. Some kinds of toothpaste have ingredients optimised for prevention of tooth wear and your dentist may advise a selection to use.
Do not brush directly after a meal when you have eaten acidic foods.
Brush twice a day: last thing at night and first thing in the morning before you have breakfast.
Use a soft to medium bristle toothbrush.
Do Not Scrub, a soft circular motion to work the bristles into all areas and crevices is best.
After brushing swish the foam around and in-between your teeth for 20 secs then spit. If you can avoid rinsing or rinse lightly with a small amount of water only this will help.
If you are on medication that has led to a dry mouth, seek medical advice it may be possible to switch to a different medicine that doesn’t. Advise your dentist of any medicines you take, do not stop any medicine without consulting your doctor.
If you suffer from acid reflux or vomiting refrain from brushing, either wash your mouth out with water or use a teaspoon of baking powder in a tumbler of water (this is very alkaline and will remove the acidity) or an alcohol-free mouthwash. Seek both medical and dental advice if you suffer acid reflux or vomiting.
If you feel you are grinding or clenching your teeth seek advice from your dentist, a biteguard will protect your teeth from excess wear.