Vogt Beatriz Farias, Souza Carlos Eduardo Chrzanowski Pereira, Silva Daniela Nascimento, Etges Adriana, Campos Maria Martha
Post-Graduation Program in Dentistry: Concentration in Maxillofacial Surgery, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Post-Graduation Program in Implantodonty: Associação Paulista de Cirurgiões Dentistas, São Paulo, SP, Brazil.
Odontology. 2016 May;104(2):211-9. doi: 10.1007/s10266-015-0204-7. Epub 2015 Apr 21.
This study aimed to evaluate the effects of White MTA (WMTA) and MTA Fillapex(®) on root resorption, when used for root canal filling, in a rat model of delayed tooth replantation, with special focus on the RANKL/RANK/OPG system. Maxillary right central incisors of male rats were extracted (total N = 48), and exposed to dry environment for 30 min. The animals were allocated into four groups: (1) WMTA; (2) MTA Fillapex; (3) Calcium hydroxide; (4) Negative control. After periodontal ligament removal, root canals were filled with the corresponding material and replanted. After 10 and 60 days, qualitative and semi-quantitative histological and immunohistochemical analyses were carried out. Analysis of variance (ANOVA) with Tukey's post hoc adjustment was used, at 10 and 60 days, to compare the experimental groups in terms of the inflammatory scores and in terms of the changes in OPG, RANK and RANKL. Both WMTA and MTA Fillapex groups displayed inflammatory and replacement resorption, with the presence of dento-alveolar ankylosis, similarly to that observed for calcium hydroxide, in either 10 or 60 days. Notably, a slight increase of the inflammatory process was observed in both MTA groups. Quantitatively, inflammation score analysis showed a significant difference between the calcium hydroxide and the control group at 10 days. On 60 days, dento-alveolar ankylosis was found significantly increased in the MTA Fillapex, in comparison to the control group (p < 0.05). For immunohistochemical analysis, the expression of both RANK and RANKL was reduced in calcium hydroxide and WMTA groups, from 10 to 60 days of evaluation, an effect that was accompanied by increased OPG immunolabelling. Otherwise, the MTA Fillapex group presented a general increase of RANKL immunopositivity, similarly to that observed in the negative control group. Our data showed that none of tested materials was able to fully prevent the root resorption, although the white MTA cement presented an outcome comparable to that seen for calcium hydroxide. MTA cements might present some advantages when considering no need of frequent changes, although the effects of MTA cements in dental avulsion still require further investigation.
本研究旨在评估白色MTA（WMTA）和MTA Fillapex（®）在大鼠延迟牙再植模型中用于根管充填时对牙根吸收的影响，特别关注RANKL/RANK/OPG系统。拔除雄性大鼠右上颌中切牙（共48颗），并使其暴露于干燥环境30分钟。将动物分为四组：（1）WMTA组；（2）MTA Fillapex组；（3）氢氧化钙组；（4）阴性对照组。去除牙周膜后，用相应材料充填根管并再植。在10天和60天后，进行定性和半定量组织学及免疫组织化学分析。在10天和60天时，采用方差分析（ANOVA）及Tukey事后检验，比较各实验组的炎症评分以及OPG、RANK和RANKL的变化。WMTA组和MTA Fillapex组在10天或60天时均表现出炎症性吸收和替代性吸收，并伴有牙槽骨粘连，与氢氧化钙组观察到的情况相似。值得注意的是，两个MTA组的炎症过程均略有增加。定量分析显示，在10天时，氢氧化钙组与对照组的炎症评分存在显著差异。在60天时，与对照组相比，MTA Fillapex组的牙槽骨粘连显著增加（p < 0.05）。免疫组织化学分析显示，从评估的10天到60天，氢氧化钙组和WMTA组中RANK和RANKL的表达均降低，同时伴有OPG免疫标记增加。否则，MTA Fillapex组的RANKL免疫阳性总体增加，与阴性对照组观察到的情况相似。我们的数据表明，尽管白色MTA水门汀的结果与氢氧化钙相当，但所测试的材料均不能完全防止牙根吸收。当考虑到不需要频繁更换时，MTA水门汀可能具有一些优势，尽管MTA水门汀在牙脱位中的作用仍需进一步研究。
