Did you know that the adult human mouth has 32 teeth? And, we have teeth as early as 6 months old. Teeth are different and have different functions. Since we are omnivores, eating both meat and plants, we need the ability to cut, tear and grind our food before it enters into the digestive system. Each type of tooth and each part of the tooth work together to function properly from childhood through adulthood. It is important for a medical assistant to know the different types of teeth and how they function. The medical assistant should also become familiar with the three different tooth numbering systems to properly chart and describe a patient’s teeth.
The Evolution of Our Teeth
A person will have two sets of teeth: the primary dentition and the permanent dentition. The first set of 20 primary teeth, commonly referred to as baby teeth, begin to erupt as early as 6 months. The primary teeth are usually fully set by the age of 2 and begin to exfoliate at the age of 6. By 12 years old, many children will have shed their primary teeth. Between the ages of 14 to 25, the individual will have completely erupted the second and third set of molars fixing the permanent teeth for the rest of their life.
The Different Types of Teeth
The human mouth is made up of four types of teeth including incisors, canines, premolars and molars.
Incisors – located at the front of the mouth, with four on top and four on bottom.
Canines – located at the corner of the arch. The canine is the longest tooth in the human mouth.
Premolars – there are four on top and four on bottom and are a cross between canines and molars. Children will not have premolars until their teeth erupt and permanent teeth replace the primary dentition.
Molars – there can be four or more molars depending on how many wisdom teeth a person has.
The Parts of The Tooth
A tooth is divided into two parts, the crown and the root. The root helps anchor the tooth into the bone. Depending on the type of root, it may have one, two or three branches. The teeth contain four types of tissue including enamel, dentin, cementum and pulp.
Enamel – makes up the crown of the tooth and is the hardest material in the body. The harder enamel forms a protective covering for the softer dentin underneath. The enamel in your teeth is made up of hydroxyapatite, phosphorous and calcium.
Dentin – makes up the main part of the tooth structure and extends almost the entire length of the tooth. It is covered by the crown on top and cementum at the root. The dentin is at greater risk for tooth decay if the enamel of the tooth wears away.
Cementum – bonelike, rigid connective tissue that covers the root of the tooth. The cementum helps anchor the tooth into the bone. The best way to protect this softer tissue from decay is proper gum care.
Pulp – found at the center of the tooth and contains the blood vessels, nerves, and soft tissues that deliver nutrients and signals to the teeth. The pulp chamber is larger at eruption but becomes smaller with age.
The Function of Teeth
Most humans are omnivores, eating both meat and plants. As such, we need teeth that can do many different functions including cutting, tearing and grinding. These functions help us break down and chew our food before entering the digestive system where our bodies will absorb nutrients from the food we eat.
Function of Incisors – designed to cut food without heavy force. The first teeth in the mouth to contact food.
Function of Canines – designed to cut and tear food that requires force. The canines are also important to properly align the teeth in the mouth as they sit at the corner of the arch. They are the best-anchored and most stable teeth since they have the longest roots.
Function of Premolars – used for chewing and grinding food.
Function of Molars – also used to chew and grind food.
The Tooth Numbering System
In addition to knowing the types and functions of teeth, the dental assistant must become familiar with the different tooth numbering systems to properly chart and describe a patient’s teeth. The three different tooth numbering systems include Universal/National System, International Standards Organization (ISO) System and Palmer Notation System.
Universal/National System – The system most often used in the U.S. is the Universal/National System, approved by the American Dental Association (ADA). The permanent teeth are number from 1 to 32. The primary teeth are lettered with capital letters from A to T.
International Standards Organization System – The World Health Organization (WHO) created the International Standards Organization (ISO) System to create a system that can be used internationally and by electronic data transfer. The ISO system uses a two-digit tooth-recording system. The first digit indicates the quadrant and the second digit indicates the tooth in the quadrant.
Palmer Notation System – each of the four quadrants are given its own bracket made up of vertical and horizontal lines. The number or letter assigned to each tooth depends on its position relative to the midline.
Are you interested in learning more about the types and functions of teeth? Are you ready to learn more about how to become a dental assistant? The Dental Assistant training program at Meridian College provides extensive hands-on training including a school externship at a dental office where you will assist the dentist in treating actual patients.
Contact Meridian College today to learn more about becoming a dental assistant.