What is the function of Cementoenamel Junction?

The cementoenamel junction is the part of the tooth where two vital substances that protect the tooth meet on the tooth’s surface.

Where is the Dentinoenamel Junction?

The dentinoenamel junction (DEJ) is the border where five different structures meet: the cervical enamel, two superficial outer dentin layers (Tomes’ granular and Hopewell-Smith hyaline layers), located over the inner circumpulpal dentin, and cementum (afibrillar acellular cementum and fibrillar cellular cementum).

Why is the Dentinoenamel junction scalloped?

In straight DEJ models, tensile stresses act at the DEJ over continuous areas in a direction, which would push the two tissues apart, thus leading to delamination of the DEJ. … These findings suggest that the scalloped nature of the DEJ confers a biomechanical advantage to the integrity of the tooth during mastication.

Why is DEJ sensitive?

As it is known, dentin is covered by enamel in the crown surface and by a thin layer of cementum in the root surface of the tooth. Dentin is sensitive to stimuli due to the lesion extension of odontoblastic process and formation of dentin-pulp complex [1, 3, 6]. Dentin and pulp are histologically different.

How do you identify a Cementoenamel Junction?

The cementoenamel junction, frequently abbreviated as the CEJ, is a slightly visible anatomical border identified on a tooth. It is the location where the enamel, which covers the anatomical crown of a tooth, and the cementum, which covers the anatomical root of a tooth, meet.

What conditions can cause exposed cementum?

People who have oral conditions such as periodontal disease or tooth damage due to misaligned teeth may also experience it. Hypercementosis mostly affects adults, and the likelihood of it occurring increases with age.

What is the appearance of the Dentinoenamel Junction?

The DEJ exhibits a scalloped appearance. The scalloped model has higher maximum tensile stresses than the straight model, but axial pressures would push the two tissue apart, leading to delamination of the DEJ during loading (mastication).

What is the Predentin?

[3] Predentin is the newly formed dentin before calcification and maturation. It is the innermost portion of dentin and is located adjacent to pulpal tissues. It is usually thick where active dentinogenesis occurs.

What is reactionary dentin?

Reactionary dentine and reparative dentine are two strategies used by the dentinepulp complex to respond to injury. The reactionary dentine is secreted by original odontoblasts, while the reparative dentine is formed by odontoblast-like cells.

How is Dej scalloped?

In addition to this fibre reinforcement, the DEJ scallops seem to have an impact on the mechanical properties: The structure of the DEJ can be described as scalloped with its convexities directed toward the dentine and concavities toward the enamel;6 each scallop houses microscallops as well as collagen fibrils.

What are the organic substances of the Dentinoenamel Junction?

Dentin is approximately 55 vol% mineral, 30 vol% organic material (primarily type I collagen), and 15 vol% fluid [46], but dentin composition varies with the age and tooth type. The organic portion of collagen is surrounded by water, and hydrogen bonding exists between the strands of the collagen.

What are Ameloblasts?

Ameloblast: One of a group of cells originating from the ectoderm from which the dental enamel is developed; an enamel cell. The ameloblasts cover the papilla of the enamel organ.

Is the Dentinoenamel junction scalloped?

The dentinoenamel junction is thought to be of a scalloped structure which has occurred as an exaptation of the epithelial folding that is undergone during ontogeny.

Is dentin hypersensitivity serious?

Prognosis. Dentin hypersensitivity may affect individuals’ quality of life. Over time, the dentin-pulp complex may adapt to the decreased insulation by laying down tertiary dentin, thereby increasing the thickness between the pulp and the exposed dentin surface and lessening the symptoms of hypersensitivity.

Can dentin hypersensitivity be cured?

They may not realize it, but patients with dentinal hypersensitivity don’t have to resign themselves to living with the problem. The most common first-line treatment for reducing pain is over-the-counter potassium nitrate dentifrice, which aims to desensitize the teeth by reducing nerve excitability.

What are the three types of relationship at the Cementoenamel Junction?

Past studies of the cementoenamel junction have illustrated that there are three distinct relationships that occur between the enamel and cementum: overlap, when the cementum extends on to the coronal enamel, edge-to-edge, when the cementum and enamel connect at the cervical line, and a gap with an exposure of dentin …

What are the types of Cementoenamel Junction?

In human teeth, the cementoenamel junction (CEJ) can have different morphologies, known as Choquet cases or types: in type 1, the cementum overlaps the enamel; in type 2, the enamel overlaps the cementum; in type 3, the relationship between the cementum and enamel is edge-to-edge; and in type 4, there is a gap between …

What is the hardest substance in your body?

Tooth enamel 1. Tooth enamel is the hardest substance in the body. The shiny, white enamel that covers your teeth is even stronger than bone. This resilient surface is 96 percent mineral, the highest percentage of any tissue in your body making it durable and damage-resistant.

Is cementum harder than dentin?

Cementum is slightly softer than dentin and consists of about 45% to 50% inorganic material (hydroxyapatite) by weight and 50% to 55% organic matter and water by weight. The organic portion is composed primarily of collagen and protein polysaccharides.

What does cementum feel like?

An important property of this material that covers the root surface is that, much like the enamel, cementum has no nerves and hence no feeling if it is exposed.

What causes cementoma?

The cause of the cementoma continues to be unknown and is linked with many sources, including trauma, nutritional deficiency, metabolic disturbances, constitutional factors, and others. Zegarelli and Kutscherl’ have collected data which suggest an association with an endocrine disturbance of an unknown nature.

Where is the apex of the tooth located?

The apex is located on the tip of the root, or on the pointed end of it. Different teeth have a different number of roots. For example, the incisors have only one root and one apex. Teeth that have two roots have two apexes and so on.

What is the axial wall of tooth?

AXIAL WALL-An axial wall is an internal wall parallel with the long axis of the tooth. PULPAL WALL-A pulpal wall is an internal wall that is perpendicular to the long axis of the tooth and occlusal of the pulp.

What are the types of dentin?

Types. There are three different types of dentin which include primary, secondary and tertiary. Secondary dentin is a layer of dentin which is produced after the tooth’s root is completely formed. Tertiary dentin is created in response to a stimulus, such the presence of tooth decay or wear.

What is Predentin made of?

Predentin, the first organic matrix secreted by odontoblasts, is composed by proteoglycans, glycoproteins, and collagens. Later-formed crystallizing centers of hydroxyapatite grow and allow for transformation of predentin into dentin.

Can enamel be restored?

Once tooth enamel is damaged, it cannot be brought back. However, weakened enamel can be restored to some degree by improving its mineral content. Although toothpastes and mouthwashes can never rebuild teeth, they can contribute to this remineralization process.

What are the 4 types of dentin?

Dentine Types

What is direct pulp-capping?

Direct pulp-capping is a method for treating exposed vital pulp with dental material to facilitate the formation of reparative dentin and to maintain vital pulp.

What is dentine bridge?

Dentinal Bridge is a new reaction tissue that preserves pulp vitality and protects it from abnormal and continuous physical stimuli (cold, hot, percussion); it is due to a series of inflammatory responses leading to the formation of a hard-calcified dentin.

What is tomes granular layer?

Tomes’ granular layer is the hypomineralized area of radicular dentin, but knowledge concerning it is limited. … In the ground sections, granules of Tomes’ layer and dentinal tubules were stained with basic fuchsin and with calcein.