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).
What forms the Dentinoenamel Junction?
Why is the Dentinoenamel junction scalloped?
As a consequence, dentine and enamel would be pushed towards each other during loading (i.e., during mastication). These findings suggest that the scalloped nature of the DEJ confers a biomechanical advantage to the integrity of the tooth during mastication.
What is DEJ in dental terms?
The dentin-enamel junction (DEJ), which is the interfacial region between the dentin and outer enamel coating in teeth, is known for its unique biomechanical properties that provide a crack-arrest barrier for flaws formed in the brittle enamel1.
What does the Amelodentinal junction do?
The dentinoenamel junction or dentin-enamel junction (DEJ) is the boundary between the enamel and the underlying dentin that form the solid architecture of a tooth. It is also known as the amelo-dentinal junction, or ADJ.
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 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.
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.
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.
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.
Where are Ameloblasts located?
Ameloblasts are cells present only during tooth development that deposit tooth enamel, which is the hard outermost layer of the tooth forming the surface of the crown.
What is Interglobular dentin?
Interglobular dentine (IGD) is an area of poorly mineralized dentine matrix. It has been reported that there is an association between the retraction of odontoblast processes (OP) and the formation of IGD. A variation of the extent of OP has been described depending on the region of the tooth and age.
