The gingiva is the pink soft tissue that we call our gums. It protects the jaw alveolar bone and roots of the teeth, and covers the neck of each tooth.
Dentine forms the major component of each tooth, and extends almost the entire length of the tooth. It is a living tissue, softer than enamel with a structure similar to bone. In contrast to the brittle nature of enamel, dentine is elastic and compressible. It is sensitive, and is protected by enamel on the crown portion and cementum on the roots. It is nourished by the pulp. The pulp chamber is the innermost portion of the tooth, lying beneath the dentine and extending from the crown to the tip of the root.
The pulp chamber holds the pulp, which is made up of soft tissue. It contains blood vessels to supply blood and nutrients to the tooth to keep it alive, and nerves to enable the tooth to sense temperature. It also contains small lymph vessels carrying white blood cells to the tooth to help fight bacteria. The cementum is a layer of hard tissue that covers the root of the tooth.
It is roughly as hard as bone but considerably softer than enamel. The connective tissues attach to the periodontal ligament, and through this bind the roots of the tooth to the gums and jaw alveolar bone.
The root canal also called the pulp canal is the open space inside the root where the pulp extends from the pulp chamber. Blood vessels and nerves from surrounding outside tissue enter the pulp through the root canal. The periodontal ligament is comprised of bundles of connective tissue fibres. One end of each bundle is attached to the cementum covering the root of the tooth. The fibres on the other end anchor the tooth root to the jaw alveolar bone and act as shock absorbers, allowing the tooth to withstand the forces of biting and chewing.
Accessory canals are smaller channels that branch off from the main root canal through the dentine to the periodontal ligament. They are usually found near the root end of the tooth apex. They supply blood vessels and nerves to the pulp. The apical foramen is the tiny opening at the tip of each root. This is what blood vessels and nerves from surrounding outside tissue pass through to enter the tooth.
The alveolar bone is the jaw bone that surrounds and supports the root of the tooth. It contains the tooth sockets within which the tooth roots are embedded. They are the first set of teeth we receive and will eventually fall out and be replaced with a second set. Primary teeth start to form when the baby is in the womb, but start to come through the gums erupt when the child is between 6 — 12 months old.
Children should have their complete set by 3 years old. Teeth tend to erupt in parallel, so for example the top molar on the left side should grow in at about the same time as the top molar on the right. In adult dentition the second set of teeth the 8 primary molars are replaced by the premolar or bicuspid teeth. The 12 adult molars erupt grow up from the gums behind the primary teeth and do not replace any; giving a total of 32 teeth.
The adult dentition is therefore made up of four incisors, two canines, four premolars and six molars in each jaw. Primary teeth are smaller, have more pointed cusps and are a whiter colour than permanent teeth. They also have thinner enamel and dentine so are more prone to wear, and have relatively large pulp chambers and small delicate roots. The crown is the top part that is exposed and visible above the gum gingiva.
The root of a tooth descends below the gum line anchoring the tooth in the mouth. The pulp chamber is the innermost portion of the tooth. A look at pericoronitis, a condition where the wisdom teeth do not have enough room to grow properly. Included is detail on causes and diagnosis. Teething can be a difficult process for infants, toddlers, and caregivers. Two-year molars are the large teeth at the back of the mouth, and when they…. Removal of the wisdom teeth is a common dental surgery, and there is a variety of reasons for doing it.
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Learn more. Teeth: Names, types, and functions. Types of teeth Number of teeth Summary Teeth help a person use their mouth to eat, speak, smile, and give shape to their face.
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So a regular consultation with a family dentist ensures healthy teeth. Premolars are similar in structure to the molars. They are found situated between canine and molar teeth. There are 8 pre-molars in a fully formed mouth and are also called bicuspids. Broadly classified as first and second premolars they have their own functions. The first premolars role is similar to that of canines.
Though not as sharp as canines, they help in tearing of the food. With two cusps at the crown, they also help in gripping the food when chewing.
The secondary premolars are located behind the first premolars and molars. They have a comparatively flat surface and can have two or 3 cusps. They help in cutting the food down to still smaller bits and aid in chewing the food.
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