Molars, which include all of your wisdom teeth, are rounded, flat teeth in the back of the mouth.
Also called molars, molars can vary in size and shape, but they are the largest teeth in the mouth. While your smaller, sharper front teeth are used for biting and tearing food, the role of molars is to grind food into pieces that are easy to swallow.
This article examines the types of molars, the purpose of wisdom teeth in particular, and the problems that can develop with these large, powerful teeth.
Types of molars
The average adult has 12 molars, three on each side of both your upper and lower jaw. Each of the three molars is of a different type:
- First molars, also called six-year molars because they come in around age 6
- Second molars, also called 12-year molars because they erupt around age 12
- Third molars, also called wisdom teeth, which appear between the ages of 17 and 21
Molars are designed to sustain large amounts of force from chewing, grinding and clenching. This is due to their large surface area and two to four roots that are firmly implanted in the jawbone.
Why do we have wisdom teeth?
Third molars, or wisdom teeth, are holdovers from our evolutionary past, when the human mouth was larger and could accommodate more teeth. They were useful in chewing particularly coarse foods such as roots, nuts, leaves and tough meats.
This type of diet was hard on the teeth—especially without the helpful maintenance tools we enjoy today, like toothbrushes, toothpaste, and floss. Thus, our ancestors’ teeth suffered significant wear and tear due to tooth decay.
Modern humans do not eat foods that require these extra teeth. However, evolution has not yet caught up to this change, so people still get these extra teeth when they reach adulthood.
Not everyone has them
Reported rates of missing molars vary by geographic location. Estimates of people who never develop wisdom teeth or are missing at least one of the four range from 5% to 37% worldwide.
The problem of wisdom teeth
Wisdom teeth have become a problem because evolution has shrunk the human jawbone. This presents a number of problems when these remaining wisdom teeth try to clench.
- As wisdom teeth form, they can be blocked by other teeth, preventing them from coming in properly. This is referred to as “affected”.
- If a wisdom tooth gets in, it can crowd the mouth and create hard-to-clean places where bacteria can thrive, leading to serious infections of the gums and surrounding tissues.
- When wisdom teeth don’t come in, you may be at risk for cysts or tumors that can damage the jawbone (mandible) and teeth if not removed.
It is very common for third molars to impinge. According to some research, up to 67% of the population can be affected by impacted wisdom teeth. However, these studies have been disputed. A figure of about 23% may be more accurate after accounting for racial differences and balancing the age at which assessments are made.
Even in cases where the third molars come in without problems, your dentist may recommend wisdom teeth removal to avoid problems that may occur later in life. Preventive surgery at a young age will allow you to heal faster and avoid complications that older people are at risk of.
How to take care of your molars
As the molars come in, known as eruption, you may experience painful inflammation and swelling along the gums. This is known as pericoronitis. Normally, it should take about four days.
To relieve pain and ensure that your teeth come in without problems, it is good to pay special attention to oral hygiene:
- Brush the area carefully with toothpaste.
- Use floss or soft picks for interdental cleaning.
- Rinse with a chlorhexidine mouthwash, which contains an antibacterial to fight gum disease.
If you feel pain, take pain relievers in tablet or pill form. Never leave medicines in the mouth next to pericoronitis. If the pain lasts more than four days or gets worse, see a dentist, as the tooth may need to be extracted.
Regular molar care
Like all teeth, once the molars have come in, they are prone to a variety of disorders or problems. If you experience pain in fully mature molars, you should see your dentist to check for the following:
Make an appointment right away if you also have swelling, fever, pain radiating to your jaw or ear, a bad taste in your mouth, or sensitivity to hot or cold, as these may be signs of a serious abscess.
Summary
Molars are the large flat teeth in the back of your mouth. They are designed to crush and grind food and withstand great force.
The three types are 6-year molars, 12-year molars, and wisdom teeth. The modern human diet no longer requires wisdom teeth, which is why they are called vestigial, meaning left over from an earlier era.
The human jaw has shrunk through evolution, and therefore there is often not enough room for the wisdom teeth to enter. This can lead to various problems and most people will have their wisdom teeth removed at some point. Surgery is safer and easier to recover from when you are young.
