Periostin a Game-changer in Periodontal Health and Disease: A Review

IntroductIonChronic periodontitis is an inflammatory disease which is characterized by a progressive gingival inflammatory response to bacterial dental plaque.It leads to clinical attachment loss, pocket formation, alveolar bone loss, increased tooth mobility, and finally the tooth loss. [1]This condition is characterized by increased secretion of inflammatory mediators such as cytokines and chemokines in the periodontal environment. [2]liva can also reveal the systemic health as well as the oral health to some extent.Whole saliva may also show the presence of periodontal disease and evidence indicates that the level of some cytokines increases in the saliva of patients with periodontitis.Assessment of the composition of saliva may provide valuable information about biochemical markers for the assessment of periodontal diseases. [1]Periostin is a hemophilic, secretory protein from the fasciclin I family.It influences cell matrix interactions, cell functions, tissue remodeling, wound repair, and type I collagen fibrillogenesis in periodontal ligament (PDL).It is induced by Transforming growth factor-β (TGF-β) and modulates matrix-cell interactions relevant to connective tissue repair. [2]Periostin serves as a necessary protein for the integrity, development, and maturity of the tissue and it is believed to play a key role in balancing and regulating homeostasis of the PDL.Expression of periostin is induced by the tumor growth factor (TGF)-β and bone morphogenetic protein-2 (BMP).It regulates collagen I fibrillogenesis in PDL and reinforces the cross-linking of collagen which improves the mechanical properties of connective tissue of PDL. [1]eriostin is an extracellular matrix (ECM) protein belonging to the fasciclin family. [3]5][16][17] HIstoryPeriostin was named in 1999 as a newly discovered factor for matricellular proteins. [6,18]Periostin is a 90 kDa glutamatecontaining secreted matricellular protein.It has 811 amino acids with EMI domain at one end of the chain followed by 4 FAS-1 domains and a carboxyl-terminal domain (Figure 1).There is a C-terminal sequence at the other end of the Background: Periostin is a matricellular protein highly expressed in periosteum, periodontal ligament and is essential for tissue integrity and maturation.It plays a role in collagen fibrillogenesis and is downregulated in periodontal disease.The goal of periodontal regenerative therapy is to predictably restore the tooth's supporting periodontal tissues and form a new connective tissue attachment of periodontal ligament (PDL) fibers and new alveolar bone.Periostin might play a pivotal part in regeneration of the PDL and alveolar bone following periodontal surgery.Recently, several studies have suggested that periostin may be an important regulator of periodontal tissue formation by promoting collagen fibrillogenesis and the migration of fibroblasts and osteoblasts.The aim of this article is to provide an extensive review of the implications of periostin in periodontal tissue biology and its potential use in periodontal tissue regeneration.