Oranges, grapefruit and other citrus fruit are highly acidic and can wear down the enamel on your teeth. Erosion of this outer layer can make you more vulnerable to tooth decay. Fruit juice and fizzy drinks are also highly acidic and the biggest culprits when it comes to tooth erosion. You don’t have to give up your glass of orange juice but brush about 30-60 minutes later, and limit other acidic drinks like coffee or cola. If you must have acidic drinks consider diluting them with water, drinking from a straw to limit tooth contact, and drinking up promptly.

Brushing correctly is the answer if you want to fend off bad breath and cavities. Both are caused by bacteria that feed on those leftover food particles between your teeth. These bacteria clump together and form a sticky layer of plaque that eventually wears away the tooth and causes cavities. Gum disease and bad breath are the other unpleasant results of plaque buildup. Brush twice a day with fluoride toothpaste, using small circular motions. Brush the entire tooth and don’t forget the gumline.

The fact is that dried fruit can stay on your teeth longer than some sweets. This is because it is sticky and adheres easily to the tooth surface. The longer sugar stays on the tooth the more chance you have of decay, as the ongoing sugar source fuels bacterial growth and acid production. By all means, keep snacking on dried fruit, but rinse with water afterwards and brush and floss after your snack.

The first baby teeth usually come through at about 6 months but some babies have visible teeth at birth. In most babies all 20 primary teeth are fully formed at birth, they just take a while to emerge. The first incisors (front teeth) usually show through the gums first, at about 6 months. Incisors, molars and canines come through at intervals up to 2 to 3 years old.

Baby teeth appear whiter than adult teeth because their enamel is thinner. The colour contrast is usually more noticeable when your child has some baby and some adult teeth.

Dental sealants are thin plastic coatings that are painted on teeth. They prevent tooth decay by sealing out plaque. They are most commonly used on children’s teeth because they are usually more susceptible to decay – especially in the back teeth. However adults can also benefit from sealants. One application can protect teeth for up to 10 years, but sealants need checking regularly. Sealants are often free on the NHS for children, or if you have a clear clinical need.

It’s not a look that anyone wants but the fact is that a black hairy tongue is actually a harmless condition. It’s caused by too much yeast or bacteria growth in the mouth, which builds up on the tiny projections on the tongue's surface. This ends up looking like a layer of "fur" as it harbours bacteria and makes the tongue look darker. Thankfully, it is rare, and good old-fashioned brushing and flossing to control the bacteria is the best remedy.

If you are having an “ouch” experience when one or more of your teeth react to heat or cold, you should see your dentist. Tooth sensitivity can be triggered by hot, cold, sweet or sour food or drink, but it also indicates the tooth is losing its protective coating. Brushing too hard, gum recession, cracked teeth or old fillings are all possible culprits. As well as seeing your dentist, you can use a soft bristled brush, toothpaste for sensitive teeth and watch what you eat. As always, good oral hygiene is a must.

Whitening toothpastes don’t typically contain bleaches. They usually contain abrasive particles or chemicals that polish the teeth and remove surface stains. To change the baseline colour of the tooth enamel requires professional whitening, carried out by a dentist who uses hydrogen peroxide or carbamide peroxide. By law, home whitening kits don’t contain anywhere near as powerful active ingredients, and the Britsh Dental Association urges caution when using these.

If you are unfortunate enough to have a tooth knocked out, putting it in milk is actually a good option to keep the tooth moist while you seek dental help. Do not rinse the tooth in water or alcohol. The best option is placing the tooth back in its socket, but the tooth needs careful handling, so avoid touching the root. If placing it back is not possible, put the tooth in a clean container of milk and head to your dentist.