What is Afibrillar cementum?
Acellular afibrillar cementum (AAC) AAC consists of a mineralized matrix containing neither collagen fibers nor cementocytes. AAC is found as isolated patches or as the most cervical part of AEFC on enamel just coronal to the cemento-enamel junction [3], [7], [8].
What are the two types of cementum?
There are two types of cementum: acellular and cellular. Both consist of a calcified interfibrillar matrix and collagen fibrils. The cellular type contains cementocytes in individual spaces (lacunae) that allow for communication with each other through a system of canaliculi. There are two types of collagen fibers.
What are the types of cementum?
There are three types of cementum: acellular cementum, cellular cementum and afibrillar cementum. Acellular cementum covers about 1/3-1/2 of the root and has little to no cellular components. Cellular cementum covers about 1/3-1/2 of the apex and is permeable.
How acellular cementum is formed?
The development of acellular cementum seems to be associated with secretion of enamel-related proteins by cells of the epithelial root sheath. Formation of the matrix for cellular cementum appears to be induced by exposure of the inner layer of the epithelial root sheath to the mesenchymal cells in the dental follicle.
What is sensitive cementum?
When cementum tooth loss occurs, the underneath dentin becomes exposed. As dentin becomes exposed, tooth sensitivity can occur. You can recognize sensitivity in the form of a short or sharp pain in one or more teeth.
What is Sharpey’s fibres?
Sharpey’s fibres (bone fibres, or perforating fibres) are a matrix of connective tissue consisting of bundles of strong predominantly type I collagen fibres connecting periosteum to bone.
What causes fenestration?
A naturally occurring fenestration leaves the exposed root surface in direct contact with either the alveolar mucosa or the gingiva. The condition may be caused by a variety of factors including tooth movement due to orthodontics, pathology (both endodontic and periodontal), root apex contours, and occlusal issues.
What is root dehiscence?
Dehiscence are isolated areas in which root is denuded of bone and root surface is covered by periosteum and overlying gingiva but the denuded are extends through the Marginal Bone. In Dehiscence there is no bone on one side of it (coronally) and is measured with the use of graduated periodontal probe.
What is acellular afibrillar cementum?
The acellular afibrillar cementum variety consists of an acellular and afibrillar mineralized matrix with a texture similar to the one constituting the bulk of acellular extrinsic fiber cementum or the one found among the collagen fibrils of fibrillar cementum varieties and of bone.
What is the cementum?
The cementum primarily covers the root, with some portion overlapping the crown. The cementum is made by specialized mesenchymal cells located on the outside of the tooth root. Once these cells come into contact with the dentin that has just been made, some differentiate and turn into cementoblasts ( Sadler, 2006 ).
What is acellular extrinsic fiber cementum?
Acellular extrinsic fiber cementum: a thin layer typically of 5-10 μm thickness extending from the coronal extent of the root throughout, consisting of a mineralized matrix formed from the inserting fibers of the periodontal ligament.
Does fibrin mimic cementum in UBCs?
Wall of a UBC thickened by abundant fibrin is shown. The pattern of fibrin can mimic cementum and, in this case, manifests as interconnecting linear structures that are rimmed in areas by osteoblasts beginning to deposit bone on its surfaces .