Pulitano Manisagian Gisela E, Benedí Daniel, Goya Juan A, Mandalunis Patricia M
Universidad de Buenos Aires, Facultad de Odontología, Cátedra de Histología y Embriología, Buenos Aires, Argentina.
Acta Odontol Latinoam. 2018 Dec;31(3):131-137.
The aim of this study was to evaluate the morphological alterations of epithelial cell rests of Malassez (ERMs) and their relationship with root resorption, in an experimental periodontitis (EP) model at 4 and 11 days. EP was induced in 14 male Wistar rats by placing a cotton thread ligature around the neck of the first lower right molar, for 4 (n=7) and 11 (n=7) days. The contralateral molar (left) was used as control. Following euthanasia, jaws were extracted and processed histologically to provide mesio-distal sections which were subject to H&E stain and histochemical detection technique with tartrate-resistant acid phosphatase (TRAP). The following histomorphometricparameters were evaluated on micrographs: bone area (BAr./TAr)(%), number of ERMs/mm2, number of cells/ERM, ERMs area (µm2), and percentage of root resorption surfaces (%RR). The results were analyzed statistically by ANOVA and Bonferronipost hoc (p≤ 0.05). Significant bone loss was observed in molars with EP compared to their controls. In the EP 4-Day group, no change was observed in the parameters with relation to the ERMs; however, in the EP 11-Day group, there was significant root resorption (%RR) (C: 3.21±3.07, EP-4D: 3.91±3.17, EP-11D: 23.67± 11.40; p≤ 0,05) and increase in ERMs area (µm2) (C: 455.87±145.42, EP-4D: 577.6±156.1, EP-11D: 1046.3± 582.9; p≤ 0,05). No TRAP+ ERM was found in either group. ERM hypertrophy may be related to ERMpartici-pation in mechanisms tending to establish periodontal homeostasis, inhibiting resorption and contributing toperiodon-tal regeneration.
本研究旨在评估在实验性牙周炎（EP）模型中，4天和11天时马拉色上皮剩余（ERM）的形态学改变及其与牙根吸收的关系。通过在14只雄性Wistar大鼠右下第一磨牙颈部放置棉线结扎诱导EP，分别持续4天（n = 7）和11天（n = 7）。对侧磨牙（左侧）用作对照。安乐死后，取出颌骨并进行组织学处理，以提供近远中切片，进行苏木精-伊红（H&E）染色和抗酒石酸酸性磷酸酶（TRAP）组织化学检测技术。在显微照片上评估以下组织形态计量学参数：骨面积（BAr./TAr）（%）、每平方毫米ERM数量、每个ERM的细胞数量、ERM面积（µm²）和牙根吸收表面百分比（%RR）。结果采用方差分析（ANOVA）和Bonferroni事后检验进行统计学分析（p≤0.05）。与对照组相比，EP组磨牙出现明显的骨质流失。在EP 4天组中，与ERM相关的参数未观察到变化；然而，在EP 11天组中，出现了明显的牙根吸收（%RR）（对照组：3.21±3.07，EP - 4天组：3.91±3.17，EP - 11天组：23.67±11.40；p≤0.05）以及ERM面积（µm²）增加（对照组：455.87±145.42，EP - 4天组：577.6±156.1，EP - 11天组：1046.3±582.9；p≤0.05）。两组均未发现TRAP+ERM。ERM肥大可能与ERM参与建立牙周稳态、抑制吸收并促进牙周再生的机制有关。
