title: The Cementocyte-An Osteocyte Relative?
abstract: Cementum is a mineralized tissue covering the tooth root that functions in tooth attachment and posteruptive adjustment of tooth position. During formation of the apically located cellular cementum, some cementoblasts become embedded in the cementoid matrix and become cementocytes. As apparently terminally differentiated cells embedded in a mineralized extracellular matrix, cementocytes are part of a select group of specialized cells, also including osteocytes, hypertrophic chondrocytes, and odontoblasts. The differentiation and potential function(s) of cementocytes are virtually unknown, and the question may be posed whether the cementocyte is a dynamic actor in cementum in comparable fashion with the osteocyte in the skeleton, responding to changing tooth functions and endocrine signals and actively directing local cementum metabolism. This review summarizes the literature with regard to cementocytes, comparing them to their closest "cousins," the osteocytes, where insights gained from osteocyte studies serve to inform the critical examination of cementocytes. The review identifies important unanswered questions about these cells regarding their origins, differentiation, morphology and lacuno-canalicular system, selective markers, and potential functions.
authors.affiliation: Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO, USA Department of Orthodontics, Shanghai Key Laboratory of Stomatology, Shanghai No. 9 Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: N
authors.initials: N
authors.lastname: Zhao
authors.affiliation: Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA.
authors.forename: B L
authors.initials: BL
authors.lastname: Foster
authors.affiliation: Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO, USA bonewaldl@umkc.edu.
authors.forename: L F
authors.initials: LF
authors.lastname: Bonewald
mesh_terms: D000818:Animals; D003739:Dental Cementum / Q000166:cytology* / Q000502:physiology / Q000648:ultrastructure; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010011:Osteocytes / Q000166:cytology*; D014092:Tooth Root / Q000166:cytology
keywords: bone; cementoblasts; cementum; extracellular matrix; odontogenesis; periodontium