The teeth are the hardest substances in the human body. Besides being essential for chewing and cutting, the teeth play an important role in speech.
Parts of the teeth include:

• Enamel: The hardest, white outer part of the tooth. Enamel is mostly made of calcium phosphate, a rock-hard mineral.
• Dentin: A layer underlying the enamel. It is a hard tissue that contains microscopic tubes. When the enamel is damaged, heat or cold can enter the tooth through these paths and cause sensitivity or pain.
• Pulp: The softer, living inner structure of teeth. Blood vessels and nerves run through the pulp of the teeth.
• Cementum: A layer of connective tissue that binds the roots of the teeth firmly to the gums and jawbone.
• Periodontal ligament: Tissue that helps hold the teeth tightly against the jaw.
A normal adult mouth has 32 teeth, which (except for wisdom teeth) have erupted by about age 13.
• Incisors (8 total): The middlemost four teeth on the upper and lower jaws.
• Canines (4 total): The pointed teeth just outside the incisors.
• Premolars (8 total): Teeth between the canines and molars.
• Molars (8 total): Flat teeth in the rear of the mouth, best at grinding food.
• Wisdom teeth or third molars (4 total): These teeth erupt at around age 18 but are often surgically removed to prevent displacement of other teeth.
Some conditions that affect the teeth.

Grinding (bruxism): Stress, anxiety, or sleep disorders can cause teeth grinding, usually during sleep. A dull headache or sore jaw can be symptoms.
Tooth sensitivity: When one or more teeth become sensitive to hot or cold, it may mean the dentin is exposed.
Cavities (caries): Bacteria evade removal by brushing and saliva and damage the enamel and deeper structures of teeth. Most cavities occur on molars and premolars.
Tooth decay: A general name for disease of the teeth, including cavities.
Periodontitis: Inflammation of the deeper structures of the teeth (periodontal ligament, jawbone, and cementum). Poor oral hygiene is usually to blame.
Gingivitis: Inflammation of the surface portion of the gums, around and between the crowns of the teeth. Plaque and tartar buildup can lead to gingivitis.
5 foods that are bad for your teeth

- Red wine
Red wine is one drink that can cause stain for your teeth. This is because of the acidic nature of the drink which roughen and open the pores within the enamel of your teeth. - Tea and Coffee
For people who always start their mornings with a cup of coffee, you are definitely subscribing to stained teeth. This is because coffee contains a chemical compound – tannins that can cause color compounds to stick to your teeth.
Tea is also bad for your teeth. It also contains tannins just like coffee and is responsible for teeth stains. This can however be reduced if you add milk to your tea, a 2014 study has said. - Energy and sports drinks
Energy drinks are good for an elevated mood and improved memory, but at the same time, they break down your teeth’s enamel and contributes to teeth stains. Energy drinks are also high in acidic content, and this is definitely bad for your teeth. - Candies and popsicles
Some sweet foods such as candies, chewing gums and ice-popsicles contain coloring agents. Some of them change the color of your tongue immediately after consumption and it’s the same for your teeth.
To avoid teeth stains, it is advised that the above foods are limited, and oral hygiene is also improved. - Fruit juices
Fruit juices containing blackberries, blueberries, pomegranates, and other dark berries are also bad for your teeth. These fruits contain a dark pigmentation that can cause teeth stains.
Other fruit juices such as cranberry, grape, beet, pomegranate, and blueberry are also on this table as they also lead to teeth discoloration.
READ ALSO: 8 HEALTH FOODS YOU SHOULD AVOID THIS INSTANT
Ways to properly take care of the teeth
- Brush and floss more often.
Plaque, the sticky buildup on your teeth, collects bacteria that cause bad breath. Trapped food also adds to the problem.
Brush your teeth at least two times each day, and floss at least once. If you’re concerned about your breath, do both a little more often. - Rinse your mouth out.
Besides freshening your breath, a mouthwash adds extra protection by getting rid of bacteria. A fresh minty taste can make you feel good. But be sure the mouthwash you choose kills the germs that cause bad breath. Don’t just cover up the smell. Rinse daily with a good mouthwash and stop bad breath at its source. - Scrape your tongue.
The coating that normally forms on your tongue can be a host for smelly bacteria. To get rid of them, gently brush your tongue with your toothbrush.
If your brush is too big to comfortably reach the back of your tongue, try a scraper. “They’re designed specifically to apply even pressure across the surface of the tongue area. This removes bacteria, food debris, and dead cells that brushing alone can’t take care of,” - Avoid foods that sour your breath.
Onions and garlic are big offenders. But brushing after you eat them doesn’t help.
The substances that cause their bad smells make their way into your bloodstream and travel to your lungs, where you breathe them out. - Moisten your mouth.
You can get tooth decay and bad breath if you don’t make enough saliva. If your mouth is dry, drink plenty of water during the day.
Chew sugarless gum or suck on sugar-free hard candy. Also try a humidifier at night to moisten the air in your house. - See your doctor.
If your bad breath continues despite your best efforts, make an appointment with your doctor. They’ll check to see if your problems are related to a medical condition.