Names and description
Crown (Corona dentis) -protrudes out of the gingiva and is a portion of dent in that is covered by enamel; is the biggest part of the tooth with its occlusal surface.
Neck of a tooth (Collum dentis) - the slightly constricted part of a tooth, between the crown and the root.
Root (Radix dentis) - is the part that extends into the upper or lower jawbones. Different types of teeth have different root formations. Some, such as incisors and canine teeth, have a single root. Molars may have one, two or three roots depending on their type and location in the mouth. At the end of each root is a small opening - blood vessels and nerves pass through this opening to enter the tooth.
Enamel (Enamelum) –Enamel forms the outermost surface of the crown of the tooth and is the hardest tissue in the body, therefore making it an ideal protective covering for a tooth. Even though the enamel is hard, it is also the most brittle under certain conditions. Composed of 96% inorganic and 4% organic materials.is essentially the tooth’s last line of defense, which protects it from basic consumed substances. Enamel is a unique part of the body, because of how a tooth develops, enamel is something that is incapable of regeneration, which makes it a very important resource to maintain and take care of. Enamel does wear down over time, which is simply a part of aging.
Dentin -is the second hardest tissue in the body, composed of 70% organic and 30% inorganic materials. Although dentin is a hard tissue, it does have elastic properties that support the enamel layer above it. Dentin includes the main portion of the tooth and is made up of microscopic passages called dentinal tubules. These tubules transmit pain stimuli and nutrition throughout this layer of the tooth. It is the second layer of the tooth and is normally covered by enamel and covers the pulp making up the majority of the tooth's structure. The color of dentin may range anywhere from yellow to grey but is typically a pale yellow and is generally what is seen penetrating through the tooth's enamel.
Cementum -is the third type of hard tissue that covers the root of the tooth in a very thin layer. It is not as hard as enamel or dentin, but it is harder than bone with a similar composition of 50% organic and 50% inorganic materials. It contains fibers that help to anchor the tooth within the bone. Cementum is light yellow in color, lighter than dentin and easily distinguishable from enamel because it lacks shine.
Pulp (Pulpa)-is the most vital part of the tooth at the core of the tooth, beneath the dentin, is the pulp cavity. This space contains the blood vessels, nerves and connective tissue that make up the "pulp." The pulp's blood supply provides nutrients that help to keep the tooth alive. The part of the pulp cavity located in the root is called the pulp canal or the root canal. The parts of the pulp that point upward toward the cusps (points of the teeth) are called the pulp horns.
Gingiva -is the pink flesh we call our gums. It lies over the bones of the jaw and hugs the tooth tightly at its neck. It ensures that no bacteria and microorganisms will enter the body. The gap between the tooth and gingival called gingival sulcus, if the gingival sulcus expands this will cause periodontal pockets
Human Dentition – The teeth that are located in the upper and lower jaws are collectively referred to as the human dentition. As humans, we have two sets of teeth during our life time.
Primary Dentition – this is the first set of teeth we get and are often referred to as baby teeth. There are 20 teeth in the primary dentition.
Permanent Dentition – is the second set of teeth we get and are often referred to as adult teeth. There are 32 teeth in the permanent dentition.
- Maxillae The upper jaw is known as the maxillae
- Maxillary Teeth Teeth located in the maxillae form an arch and are referred to as maxillary teeth
- Mandible The lower jaw is called the mandible
- Mandibular Teeth The teeth located in the mandible are referred to as mandibular teeth
There are several terms that help to define locations on and around the teeth and these terms are used often to refer to specific areas of the mouth when describing conditions there.
- Posterior towards the back of the mouth
- Anterior towards the front of the mouth
- Mesial towards the midline of the mouth
- Distal away from the midline of the mouth
- Buccal any area on the cheek side of the teeth
- Lingual any area on the tongue side of the teeth
- Facial any area on the cheek or lip side of the teeth
- Palatal any area on the tongue side of the maxillary teeth
- Occlusal any area on the chewing surfaces of the back teeth
- Incisal any area on the biting surfaces of the front teeth
In both the maxillary and mandibular arch there are similar teeth and only four types of teeth. This includes the incisors, the canines, the premolars and the molars. Each of these teeth is located in a different area of the mouth and serves different functions.
Incisors – the four front teeth in the mouth are known as incisors. They are located in both the maxillary and mandibular arches. The two center teeth are known ascentral incisors and the teeth on either side of them are known as lateral incisors. All of these teeth are responsible for cutting or biting food. They act like scissors.
Canines– The teeth located distal to the lateral incisors are known as canines. These teeth form the corners of the mouth. There are two canines in the maxillary arch and two canines in the mandibular arch. These teeth are responsible for tearing food particles when chewing.
Premolars – the teeth located distal to the canines are known as premolars. There are four premolars in each arch and two are located behind each canine in the arch. These teeth are smaller than the molars and are responsible for crushing food. These teeth are only present in the permanent dentition. The primary dentition only consists of incisors, canines and molars.
Molars – there are normally six molars in each arch; three on the left and three on the right side. They are referred to as first, second and third molars. Some people never develop third molars and these molars are called wisdom teeth. The role of the molars in chewing is to grind the food.
Tooth numbering system
In order to effectively and efficiently refer to teeth we often use numbering or lettering systems. There are several systems that are used throughout the world. The most widely used system in the world is the International Numbering System. This