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How Forensic Dentistry Works

By:Shanna Freeman&Melanie Radzicki McManus|

Types of Teeth

Surfaces of the back teeth
Surfaces of the back teeth
2022 HowStuffWorks

Adults typically have32 teeth: four incisors, four canines, eight premolars, 12 molars and four wisdom. Since there are multiple teeth in each group, each individual tooth needs its own designation. There are dozens of methods for labeling teeth in use, but thethree most popularare theUniversal Numbering System,Palmer Notation Numbering Systemand theFDI (Fédération Dentaire Internationale) World Dental FederationNotation.

In the United States, most dentists use the Universal Numbering System. In this system, each of the 32 adult teeth is assigned a number. Number one is the upper-right third molar, while number 32 is the lower-right third molar. The 20 deciduous, or baby, teeth are designated by the letters A through K or the number-letter combination of 1d through 20d.

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Some teeth, like molars, havemultiple surfaces. Each of these surfaces has a name. The center of the tooth is the biting surface, known as theocclusal. This surface has two elements: thecusps, or raised parts, and thegrooves, or indentions. Themesialsurface of the tooth is toward the front of the mouth, while thedistalis toward the back. The side toward the inside of the mouth is called thepalatalsurface on the upper jaw and thelingualon the lower jaw. The tooth surface facing the cheek is thebuccal. So if you get a filling on the distal of number 15, that means it's on the surface facing the back of the mouth on your upper second molar (or 12-year molar).

When you visit the dentist for a checkup, the dentist makes a notation about each tooth to show variations (e.g., chips), and dental work such as fillings, crowns and bridges. The dentist also includes observations about the health of your teeth, like receding gums or signs of periodontal disease. Most dental visits involve taking sets ofX-rays,这也可以显示工作18新利最新登入not easily seen, like root canals.

In the next section, we'll look at how forensic dentists use these records to identify teeth.

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