Putative role of epithelial rests of Malassez in alleviation of traumatic occlusion

A Review of the Epithelial Cell Rests of Malassez on the Bicentennial of Their Description

“…At the completion of the experiment, there were more ERM clusters seen within the PDL space compared to the acute insult phase, and each cluster contained 2 to 3 times more ERM cells than in control animals. 57 A majority of the ERM cells had characteristics of an enhanced secretory apparatus; other ERM cells displayed ultrastructural changes suggestive of impending apoptosis. The authors concluded that following traumatic occlusal injury, the ERM proliferated and played an active role in repair of the PDL.…”

“…Experimental and control animals were serially killed, and the effect of traumatic occlusion on ERM cells in vivo was studied using light and transmission electron microscopy. 57 The "acute insult phase" lasted approximately 3 weeks, during which time the PDL fibers became disorganized, and the number of ERM clusters increased near the cementum, but also adjacent to prominent blood vessels close to the alveolar bone. Some of the ERM cells displayed ultrastructural characteristics suggestive of enhanced protein synthesis such as increased prominence of the rough endoplasmic reticulum and more mitochondria.…”

“…The ultrastructural differences between ERM cells implied functional heterogeneity, with some cells appearing to be adapted for phagocytosis and other cells appearing to be adapted for enhanced protein synthesis. 57 Many authors have suggested that the ERM play a role in maintaining the width of the PDL space. 25,26,[58][59][60] Evidence for this came from early studies performed in dogs and monkeys where teeth were experimentally extracted and then replanted.…”

“…There is mounting evidence that the ERM play a functional role in periodontal physiology. 56,57 In an experimental study published in 2015, a custom-fitting cast metal crown was applied onto the occlusal surface of the right maxillary first molar tooth of laboratory rats. 57 The prosthetic was designed to cause an acute increase in occlusal pressure sustained by the opposing mandibular molar tooth.…”

“…56,57 In an experimental study published in 2015, a custom-fitting cast metal crown was applied onto the occlusal surface of the right maxillary first molar tooth of laboratory rats. 57 The prosthetic was designed to cause an acute increase in occlusal pressure sustained by the opposing mandibular molar tooth. Experimental and control animals were serially killed, and the effect of traumatic occlusion on ERM cells in vivo was studied using light and transmission electron microscopy.…”