Is cementum cellular or acellular?
Cementum has historically been classified into cellular and acellular cementum by inclusion or non-inclusion of cementocytes. Generally, acellular cementum is thin and covers the cervical root, whereas thick cellular cementum covers the apical root (Fig.
What are intrinsic fibers of cementum?
Collagen fibers produced by cementoblasts are intrinsic fibers of cementum and are confined to that layer. Collagen fibers formed by fibroblasts of the PDL (E) forming the principal fiber bundles, are partly incorporated into the cementum (A). They are referred to as extrinsic or Sharpey’s fibers (F).
What are extrinsic fibers and intrinsic fibers in cementum?
1) Cementum contains two types of fibers, i.e. extrinsic (Sharpey’s) fibers which are embedded ends of the principal fibers and intrinsic fibers which are fibers of cementum proper.
Where is the acellular cementum?
tooth root
Acellular cementum is the thin, mineralized tissue covering the cervical portion of the tooth root, important for attachment of the periodontal ligament (PDL) to the root surface (Bosshardt, 2005; Foster et al., 2007).
What is the structure of the intrinsic fibers of cementum?
(F) Intrinsic fibers encircle extrinsic fibers or meander among them in a tangential section parallel to cementum surface. 3. Structure of cementum 3.1. Acellular extrinsic fiber cementum (AEFC) Generally, AEFC covers cervical root surfaces in both permanent and deciduous teeth.
What is the acellular cementum?
The acellular cementum is the initially formed cementum found on the cervical portion of the root. Cellular cementum is found on the apical portion of the root and is deposited when the tooth enters its functional stage (Table). However, this arrangement is not always present and deviations do exist.
What is the cementum of the tooth?
As the name indicates, this type of cementum neither contains cells nor collagen fibers. It is a product of cementoblasts and is found only in the cervical areas of the tooth. Its distribution varies from tooth to tooth and CEJ of the same tooth. The thickness of this cementum in humans varies from 1-15 μm.
What are the molecular factors of cementum 347 and 348?
These molecular factors are responsible for cell migration and mineralization of cementum 347, 348. It has been shown that cementum also contains chemokines and integrins, which promote differentiation and proliferation of some periodontal cell types 349.