How often has it happened that you visit your dentist and he talks about enamel, pulp and uses all dental terminologies to describe different parts of teeth and you get confused? Sometimes it is important to know the tooth anatomy. Most of us use layman dental terminologies as lower front teeth or upper back teeth. But it would be great if you could identify parts of teeth such as crown, neck, etc.
In the article, you will learn different types of teeth and a tooth anatomy.
What are teeth?
Teeth are hard structures of the human body composed of calcium, phosphorus, and other minerals. Most of us think teeth as bone which is not the case. Teeth help break down food, affect our appearance and speaking abilities.
Humans have two sets of teeth are they are –
Primary or deciduous set
The primary set of teeth comprise of 20 teeth in which 10 teeth are placed on each arch. They are replaced by permanent teeth by the age of 12-14 years. This set includes incisors, canines, and molars.
This set comprises of 32 teeth. They replace the primary teeth and if you lose your permanent teeth due to negligence or some mishap, you will have to get a replacement since no new tooth will regrow.
Functions of teeth
You might think that the major function of teeth as chewing. But there are other functions too and they are –
The main function of teeth is to help tear food items into smaller bits and then grind them to small pieces which one can easily swallow. Small fragments of food assists in the digestion of the food.
In the absence of teeth, there will be insufficient chewing and break down of food. This can lead to a problem with digestion.
Teeth have an important role to play in case of how you look. The teeth in the visible areas shape individual personality. For example, canine teeth help maintain the lips in position.
The position, shape, and shade of teeth play an important role in your appearance.
Teeth help us with pronunciation. Missing teeth affect a person’s pronunciation especially the upper front teeth.
Different types of teeth
We have four types of teeth in our oral cavity. Each type performs a different function. The different types of teeth are –
Incisors are most visible of all teeth due to their position in the oral cavity. They have two subtypes as central incisor and lateral incisors. A person has two central incisors and two lateral incisors in each jaw.
Central incisor is located in front part of the jaw. Usually, the midline of the face passes between the two central incisors. The lower central incisors are smaller than the upper central incisors.
They have a single root. These teeth help in tearing and grinding of food and play an important part in the pronunciation of consonants.
Lateral incisors are located between the central incisors and canines. They are smaller in size than the central. They help in tearing and grinding of food and play a role in aesthetics, albeit slightly less important than the central incisors.
Canines are also called the cornerstone of the oral cavity. They are four in number as two in the upper jaw and two in the lower jaw. The cusps of canines are pointed and help in tearing food.
Canines withstand lateral forces during chewing and also the longest root. They also form the transition between front and back teeth. They play an important role in esthetics.
These are absent in primary teeth set. They are also called bicuspids and are located between canines and molars. Premolars have two cusps, and they help in both grinding and tearing of food.
The first upper premolar has two roots, and the others have a single root, but variations exist.
The most posterior teeth and adults have 12 molars, six in each jaw. The first molar is present behind the premolars. They erupt at the age of 6 years, behind the milk molars. The second molars erupt around age 12.
The third molars or the wisdom tooth erupt around age 20, but this varies from one person to another. The primary function of molars is the grinding of food during mastication.
These teeth have 4-5 cusps and three or two roots. They are important abutment teeth when a patient requires a fixed dental bridge.
Crown is the visible portion of the teeth in the mouth. It is covered by enamel and is known as the crown of the tooth. Depending on the type of tooth, the crown varies in shape and size.
The root is embedded in the tooth socket and anchors the tooth. It is not visible usually. The root is attached to the jaw bone by a periodontal ligament which is specialized connective tissue fibers.
A tooth may have one or more roots depending on the type of tooth.
Enamel is the hardest substance of the body and outer covering of the crown. It is thickest at the cusps and thinnest at the borders. The color of normal enamel ranges from light yellow to grayish white.
Enamel is translucent, so the color of dentin affects the color of enamel. Enamel doesn’t contain any nerves or blood vessels. But the wearing of enamel happens over time in the form of attrition, abrasion, etc. Food items like coffee, tea or cigarette can stain enamel.
Dentin is present between enamel or cementum and the pulp. Dentin is grayish-white or yellow. Dentin is softer than enamel and decays faster than the enamel. Dentin acts as a protective layer for the pulp and supports the crown of the tooth.
The pulp is the innermost layer of a tooth and contains the nerve endings and blood vessels. Odontoblasts lie between dentin and pulp and initiate dentin formation.
Dental pulp ensures vitality and nutrition of tooth. The portion of pulp lying in the crown is known as coronal pulp. The portion of pulp lying in the root is known as radicular pulp.
This portion lies enclosed in the pulp chamber in the crown of the tooth. The shape and size of the tooth determine the shape of the pulp chamber for that particular tooth.
It is located in the root of the tooth. Space which houses the pulp is called the root canal. Root canals vary in curvature, shape, size, and number.
The apical foramen is the opening that connects the root canal with the periapical tissue. Continuous deposition of dentin causes the pulp to become smaller as the tooth ages.
This layer covers the root of the tooth. Cementum is yellowish and softer than both dentin and enamel. Cementum serves as a medium for periodontal ligaments to attach to the tooth surface.
Gum recession causes the cementum to be exposed- in such areas where cementum is exposed, the patient will have extreme sensitivity to hot and cold stimuli.
Over to you on tooth anatomy
There are so many dental terms which could be sometime overwhelming. You can either memorize tooth anatomy and parts of teeth or bookmark this article for later reference.
Now when you visit the dentist and hear dental terms such as pulp, cementum, etc., you will understand the context clearly.