It is known that the space of the periodontal ligament pdl is maintained throughout life. The aim of this study was to investigate the behavior of cells from epithelial rest of malassez erm against stretching force. However, little is known about the precise role of the periodontal membrane during this procedure. Morphological changes in the epithelial rests of malassez erm and the development of odontogenic tumors in the molars of female lewis rats treated at 4 weeks of age with a single intraperitoneal injection of 50 mgkg of nmethylnnitrosourea mnu were examined at 12, 18 and 30 weeks of age. Figure 1 epithelial rests of malassez from a subject no. Role of the epithelial cell rests of malassez in periodontal. The follicle of a surgically removed impacted premolar was cut into small pieces which were incubated in the presence of 125 i. Louischarles malassez 21 september 1842 22 december 1909 was a french anatomist and histologist born in nevers, department of nievre. The epithelial cell rests of malassez and the genesis of the. Pdf epithelial rests of malassez express immunoreactivity.
Zhenhua yang, yanjiao li, xiaojie ma, lin shen, zhihe zhao and fang jin affiliation. Surprisingly, this cell type is poorly described and is often disregarded in the context of periodontal research. Malassez epithelial rests definition of malassez epithelial. Some studies reported that erm may play a role in maintaining a stable environment of. Proliferation of the epithelial rests of malassez to form the lining of inflammatory dental cysts thus appears to be associated with a change from an unusual epithelial phenotype to that of a. Immunohistochemical reaction showing wide spectrum screening brown colour distributed in cells of ectodermal origin. The epithelial cell rests of malassez a role in periodontal regeneration. Effect of stretching force on the cells of epithelial rests.
Ermcultured cells were stretched for 1 hour, at the cycle of 18% elongation for 1 second followed by 1second relaxation. Proliferation of epithelial rests of malassez following. Autotransplantation of third molars is frequently undertaken in order to restore a perfect occlusion and to improve mastication following a substantial loss of molars. Some studies have reported that the epithelial rest of malassez erm most probably contributes to the maintenance of the pdl width. The pdl contains epithelial cells which are form close to the cementum. The epithelial cell rests of malassez and the genesis of. The significance of epithelial rests of malassez in the periodontal ligament david keinan, dmd, msc, mha, phd, and robert e. They are reported to appear in rabbits in cord or netlike formations or as isolated islands near the cementum peters et al. It has been demonstrated that hertwigs epithelial root sheath hers has an important role in root development, closely related to development of cementum epithelial rests of malassez erm as the residuum after hers fragment, and is the exclusive epithelial structure in the mature periodontal ligament. Role of the epithelial cell rests of malassez in the. However, observation of the thick horizontal serial sections revealed that the epithelial rests formed a network in. The epithelial cell rests of malassez erm are an integral part of the periodontal ligament and are considered to play an important role in dental pathology. Epithelial remnants derivatives linkedin slideshare. The purpose of this study was to isolate and characterize cells derived from human erm, and compare them with cells derived from matched normal oral mucosa nom.
Periodontitis is a highly prevalent inflammatory disease that results in damage to the toothsupporting tissues, potentially leading to tooth loss. Methods the authors performed a pubmed search on the term epithelial rests alone or in combination with malassez. Malassez 18421909, french histologist epithelial cells in the periodontal ligament derived from hertwigs epithelial root sheath. Periodontitis is a highly prevalent inflammatory disease that results in damage to the toothsupporting tissues, potentially leading to. He served with the 5th ambulance corps during the francoprussian war, afterwards returning to paris, where he worked with distinguished physicians that included claude bernard, jean. This cells were described by malassez in 1889 and are the remnants of hartwigs epithelial root. Although there was no timedependent increase in the number of erm in the control. The erm is separated from hertwigs epithelial root sheath hers at the embryonic stage of tooth root development. Immunohistochemical localization of epithelial rests of. The epithelial rests of malassez erm represent a group of cells in the periodontal ligament classically consisting of latent or quiescent structures associated with pathological processes. Morphometrical analysis of epithelial rests of malassez erm the number of erm per rat remained low in control rats 12. Role of the epithelial cell rests of malassez in the development, maintenance and regeneration of periodontal ligament tissues. Epithelial cell rests of malassez erm are quiescent epithelial remnants of the hertwigs epithelial root sheath hers that are involved in the formation of tooth roots.
Proliferation of epithelial rests of malassez following auto. Toronto, ontario, canada faculty of dentistry, university of toronto activation of the epithelial cell rests of malassez, both in. A bilayer of hers is distinguishable at the apex but has lost its continuity at the level of the ameloblast layer. However, recent evidence shows that these structures cannot be considered only as cellular debris. Epithelial rests of malassez express immunoreactivity of. An ultrastructural evaluation of the relationship between epithelial rests of malassez and orthodontic root resorption and repair in man. Nmethylnnitrosoureainduced changes in epithelial rests. Therefore, we investigated if the epithelial rests of malassez persist in the periodontal ligament of auto. Erm cells are unique epithelial cells that remain in periodontal tissues throughout adult life. This study investigated the effect of orthodontic relapse on the proliferation of fibroblast and.
The epithelial cell rests of malassez and the genesis of the dental cyst a. A histological appearance of hertwigs epithelial root sheath hers and subsequent formation of epithelial cell rests of malassez in a 10d postnatal mouse molar stained with azan. Malassez7 was the first to detail the histological characteristics of epithelial rests and their distribution in the periodontal ligament. They have a functional role in the repairregeneration of cement or enamel. Human odontogenic epithelial cells derived from epithelial. In longitudinal and transverse slices of human specimens, malassez noted the presence of epithelial cells that persisted around the roots figs 1, 2 and 3. They can proliferate in the presence of inflammation, possibly leading to cyst formation. Oct 19, 2010 autotransplantation of third molars is frequently undertaken in order to restore a perfect occlusion and to improve mastication following a substantial loss of molars. The aim of this study was to establish primary cell cultures of human erm, characterize the cytokine profile. He studied medicine in paris, where he worked as an interne from 1867. Effect of stretching force on the cells of epithelial. Therefore, we investigated if the epithelial rests of malassez persist in the periodontal ligament of autotransplanted teeth.
Epithelial cell rests of malassez contain unique stem cell. Nmethylnnitrosoureainduced changes in epithelial rests of. Pdf the epithelial cell rests of malassez a role in. Predictable and complete periodontal regeneration following periodontitis has been the ultimate goal of periodontal treatment. Pdf the effect of orthodontic relapse on the proliferation. Hsp70 mrna expression by cells of the epithelial rest of. The purpose of this study was to isolate and characterize cells derived from human erm, and compare them with cells derived from matched normal oral. In dentistry, the epithelial cell rests of malassez erm or epithelial rests of malassez pax epithelialis pediodontii are part of the periodontal ligament cells around a tooth. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Epithelial abnormalities therefore also influence the morphology and function of the dental root and pdm.
Given their embryological origins and persistence in adult periodontal tissue, recent research has investigated whether the erm could be useful as stem cells to regenerate tissues lost as a consequence. It is considered that these cell rests proliferate to form epithelial lining of various. We investigated the notion that erm contain a subpopulation of stem cells that could undergo epithelial. Isolation and characterization of cells derived from human. Hertwigs epithelial root sheath, epithelial cell rests malassez, periodontium development, periodontal regeneration, cementogenesis, stem cells. In vitro characterization of the cytokine profile of the. They are discrete clusters of residual cells from hertwigs epithelial root sheath hers that didnt completely disappear. The epithelial cell rests of malasse are discrete clusters of residual cells from hertwigs epithelial. The epithelial rests of malassez erm are development residues of hers in the pdm. Epithelial rests of malassez definition of epithelial rests. This cells were described by malassez in 1889 and are the remnants of hartwigs epithelial root sheath.
Jan 07, 2018 the pdl contains epithelial cells which are form close to the cementum. The epithelial cell rests of malassez erm are odontogenic epithelial cells located within the periodontal ligament matrix. While their function is unknown, they may support tissue homeostasis and maintain periodontal ligament space or even contribute to periodontal regeneration. The significance of epithelial rests of malassez in the. Epithelial rests of malassez express immunoreactivity of trka. The epithelial rests of malassez erms might represent a valuable source of oral epithelial cells with stem cell properties. Epithelial rests of malassez pdf new pdf download service.
The epithelial cell rests of malasse are discrete clusters of residual cells from hertwigs epithelial root sheath hers that didnt. Changes in the supporting tissues of submerged deciduous molars with and without permanent successors. Very intense binding was localized in the epithelial cell rests of malassez, whereas only background labelling was seen in fibroblastic cells. The characteristics of epithelial cell rests of malassez. Hertwigs epithelial root sheath, epithelial cell rests malassez, periodontium development, periodontal. Epithelial remnants derivatives ahmad amro baradee 2. The cells without addition of stretching force were used as controls. Nov 26, 2018 the epithelial rests of malassez erms might represent a valuable source of oral epithelial cells with stem cell properties. The epithelial cell rests of malassez erm were first described in 1817, yet their significance has remained an enigma for more than 200 years.
510 1446 1252 1479 1098 99 1440 1643 224 1613 599 799 652 1329 1101 1173 196 675 1472 726 1469 48 1094 1602 435 179 275 1355 544 167 408 851 540 620 907 1226 584 1098 57 522