Dental Health The Functions of Molar and Wisdom Teeth Molars are the tough workhorses of human teeth By Shawn Watson Shawn Watson Shawn Watson is an orthodontic dental assistant and writer with over 10 years of experience working in the field of dentistry. Learn about our editorial process Updated on November 20, 2021 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Edmund Khoo, DDS Medically reviewed by Edmund Khoo, DDS Edmund Khoo, DDS, is board-certified in orthodontics and is a Diplomate of the American Board of Orthodontics. Learn about our Medical Expert Board Print Referred to as molars or molar teeth, these are the flat teeth located at the back of the mouth. They can vary in size and shape but are the largest teeth in the mouth. Molars are rounded and used for grinding food into easily swallowed pieces. The smaller and sharper front teeth are used for biting and tearing food. Molars are designed to sustain great amounts of force from chewing, grinding, and clenching, and each molar is anchored to the jaw bone with two to four roots. Zinkevych / Getty Images The average adult has twelve molars, with six in the upper jaw (identified by your dentist as "maxillary" for their location in the upper jaw) and six in the lower jaw (identified as "mandibular" by the dentist for their location in the lower jaw). Each side of the upper and lower jaw has three molars. Types of Molars There are three types of molars. These come in after a child loses their baby teeth: First molars, also called the six-year molars because they are the first of the three to erupt around age six.Second molars, also called the twelve-year molars because they erupt around age 12.Third molars, or wisdom teeth, which appear between the ages of 17 and 21. Anatomically, molars are designed to sustain great amounts of force from chewing, grinding and clenching, by having a large crown and two to four roots firmly implanted in the jaw bone. Why Do We Have Wisdom Teeth? The third molars, or wisdom teeth, are vestiges from our evolutionary past when the human mouth was larger and more accommodating to additional teeth. These additional teeth were useful in chewing especially course foods, such as roots, nuts, leaves, and tough meats. This type of diet was tough on the teeth—especially without the helpful maintenance tools we enjoy today like toothbrushes, paste, and floss—so our ancestor's teeth were subject to significant wear and loss due to tooth decay. Even with the current popularity of "Paleo diets," modern humans do not consume foods that require these extra teeth. Our foods are generally far softer, and with cooking and utensils, the day of the useful wisdom tooth has passed. Evolution, however, has not caught up with us yet, and so we still get those extra teeth late in our youth. The Problem of Wisdom Teeth Though it hasn't dumped our wisdom teeth yet, evolution has, unfortunately, made some adjustments to the size of our jawbones throughout our history. The jaws of modern humans are smaller than our ancestors. This presents a range of problems when those vestigial wisdom teeth try to squeeze in. When wisdom teeth form, they can become blocked by our other teeth, and they're referred to as being "impacted." If a wisdom tooth partially erupts, this can create a hard-to-reach haven for bacteria that can lead to serious infections of the gums and surrounding tissue. Wisdom teeth may also never erupt. This carries with it problems as well, including potential development of cysts or tumors that can do considerable damage to the jawbone and teeth if left unaddressed. These problems are the reason many people need to have their wisdom teeth removed. It is recommended that this surgery is performed during young adulthood when any complications are least likely and minimal. Some people may have no immediate need to have their wisdom teeth removed, because they come in without issues: One study puts the number at about 15 percent of the population. Even in these cases, it may be recommended that the wisdom teeth be removed to avoid problems that might develop later in life when surgery has more potential for complications and longer healing times. Frequently Asked Questions What causes pain in the molars? Some causes of molar pain can include:CavityBroken or cracked toothAbscessed toothDamaged fillingGrinding your teethContact your dentist if the pain is severe or lasts more than one or two days. Also make an appointment right away if you also have swelling, fever, earache, or pain when opening your mouth wide. Learn More: Causes of Tooth Pain and Treatment Options When do baby molars come in? Your baby's first molars will probably begin to come in between 13 and 19 months old. The last set of baby molars may finish coming in around 25 to 33 months old. When do kids lose their molars? It varies for different kids. On average, kids tend to lose their baby molars between 9 and 12 years old. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 7 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Teeth eruption timetable. Cleveland Clinic. Ghoncheh Z, Zade BM, Kharazifard MJ. Root morphology of the maxillary first and second molars in an Iranian population using cone beam computed tomography. J Dent (Tehran). Jung YH, Cho BH. Prevalence of missing and impacted third molars in adults aged 25 years and above. Imaging Sci Dent. 2013;43(4):219–225. doi:10.5624/isd.2013.43.4.219 Von Cramon-Taubadel N. Global human mandibular variation reflects differences in agricultural and hunter-gatherer subsistence strategies. Proc Natl Acad Sci USA. 2011;108(49):19546-51. doi:10.1073/pnas.1113050108 Fernandes MJ, Ogden GR, Pitts NB, Ogston SA, Ruta DA. Actuarial life-table analysis of lower impacted wisdom teeth in general dental practice. Community Dent Oral Epidemiol. 2010;38(1):58-67. doi:10.1111/j.1600-0528.2009.00501.x Cleveland Clinic. Toothache. American Dental Association. Eruption charts. Additional Reading Anatomy and development of the mouth and teeth. Stanford Children's Health.