Teeth, you try to preserve them as long as possible by brushing, gargling, flossing etc. But why are they so important? They are obviously needed to chew food and have an invaluable superficial value, but is that it? While most people would say yes, any forensic anthropologist would highly disagree.
Teeth can tell you more information about someone than you would think. For example, to determine the age of a child, an anthropologist looks at the teeth. Since teeth grow and fall out at predictable rate, close approximations are possible. Baby teeth start coming out at seven months and are full grown by two years. At the age of 6-7 years, permanent incisors and first molars begin to erupt. Between the ages of 7 and 8 lateral incisors erupt, canines at 10 and 11, first and second premolars between 9 and 12, and second premolars at 10 at 12. The last teeth to erupt are the third molars, which erupt when someone is between 17-25 years old.
Beside age, anthropologist can also guess someone's race by looking at teeth. To anthropologist, race is broken up to 3 broad racial groups; Caucasoid, Negroid, and Mongoloid. Mongoloids, which also include Asians and Native Americans, have shovel-shaped incisor teeth. Caucasoids have a facial skeleton, which is rough and elongated. Using this knowledge, by looking at the projecting chin around the jaw one can determine someone to be a Caucasoid. In cases of Hawaiian descent, the people have a distinctive-shaped jaw, called a rocker jaw. When the mandible is placed on the table and gently tapped, it will rock because of the rounded jawbone. In the case of Negroids, anthropologist looks not at the teeth themselves but at the bone between the bottom of the nose and the upper teeth to project outward.
Up till now we have been looking at teeth at the physical level, however in certain cases a more detailed analysis of the teeth's components is called for. Teeth are mainly composed of calcium, phosphorus, oxygen, carbon, nitrogen, and hydrogen. However teeth also contain certain trace elements. These elements can be infused by the body and used to make the human body work properly, but they can also be absorbed. By examining these trace elements invaluable evidence can be discovered.
For example, strontium is an element found in soil that is absorbed particularly into teeth, where thick dental enamel covers and preserves it. Plant-eaters retain more strontium than meat-eaters do and omnivores such as humans who eat both meat and plants have an intermediate level of strontium. Early hominid fossils of Australopithicus robustus were tested for strontium, and the results indicated that these particular ancestors were strictly vegetarians.
By matching the strontium isotopes in teeth with the strontium in soil samples, scientists can locate the source of food. By examining the oxygen isotopes that are absorbed into the human body from the drinking water one can identify an ancient person's origins. For example, a person who spent his or her life drinking rainwater from the South American tropical rain forest will have a different isotope concentration than a person who spent his or her life drinking rainwater that fell on the arctic.
These types of analyses tell us information about history that would previously be unknown. For example, analyzing for lead tells us that lead poisoning was common throughout the ages. Romans had high lead levels from ingesting it from wine vessels and cooking utensils and absorbing it through the skin from women's cosmetics. Lead levels in early American colonists reveal class distinctions. Only the wealthiest people who could afford pewter containers and glazed pottery were poisoning themselves with lead. The poor did not have such high levels in their bones. Who would have thought one could determine this much information just by looking at bones and teeth?
However, in this day and age the most useful and most common use of teeth is identification. Everyone knows that the first thing used in identification is fingerprints. But what if there is no matching fingerprints, or the body was so badly damaged fingerprints couldn't be taken. However, while the body is frail and cannot withstand many mediums, teeth are very strong and can last long after the body does. It is for this reason that teeth are used for identification. Teeth, like fingerprints are very unique in that no two are exactly alike. One can simply look at the teeth indentations and compare them with dental records. Or, teeth x-rays can be compared. Most people have had their teeth x-rayed at the dentist's office and x-rays are very accurate and unique.
So the next time you brush your teeth know that you're saving more than just your smile. You're saving one of the single most important physical things about yourself. Your teeth, if kept well, will last much longer than you will. They will also tell more about you than just about any other single physical thing…and all you have to do to keep them is to brush two times a day and floss regularly.
REFERENCE:
1.Talking Bones By: Peggy Thomas