Martins Débora C, Souki Bernardo Q, Cheib Paula L, Silva Gerluza A B, Reis Igor D G, Oliveira Dauro D, Nunes Eduardo
a Currently serving the Brazilian Army Dental Service, Manaus, Brazil; Former Orthodontic Resident, Graduate Program in Dentistry, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Brazil.
b Associate Professor of Orthodontics, Graduate Program in Orthodontics, Pontifical Catholic University of Minas Gerais, Belo Horizonte, Brazil.
Angle Orthod. 2016 Jan;86(1):39-45. doi: 10.2319/011015-20.1. Epub 2015 May 4.
To compare external root resorption (ERR) when bands and wires are used as orthodontic anchorage during rapid maxillary expansion (RME).
Histologic analysis was performed on 108 sites from 18 maxillary first premolars and on 36 sites from six mandibular first premolars in nine subjects (mean age = 15.2 ± 1.4 years) 3 months after RME. Maxillary teeth were pooled into two groups (n = 54 each) according to the type of orthodontic anchorage (band group [BG] vs wire group [WG]). Anchorage type was randomly chosen in a split-mouth design. Mandibular first premolars, which were not subjected to orthodontic forces, were used as the control group (CG).
All premolars in the BG and WG showed ERR at the level of the cementum and dentin. Repair with cementum cells was observed in all resorption areas, but complete repair was rarely found. No statistically significant difference was found between the BG and WG with regard to the ERR. No association was found between the root height position (middle or cervical third) and the incidence of ERR. Buccal root surfaces showed a higher amount of ERR compared with the palatal and interproximal surfaces. ERR was not found in any teeth in the CG.
All maxillary first premolars subjected to RME showed ERR and partial cementum repair. Banded teeth did not develop more ERR than nonbanded anchorage teeth.
比较快速上颌扩弓（RME）过程中使用带环和弓丝作为正畸支抗时的牙根外吸收（ERR）情况。
对9名受试者（平均年龄=15.2±1.4岁）的18颗上颌第一前磨牙的108个部位以及6颗下颌第一前磨牙的36个部位在RME后3个月进行组织学分析。根据正畸支抗类型（带环组[BG]与弓丝组[WG]）将上颌牙齿分为两组（每组n = 54）。在半口设计中随机选择支抗类型。未施加正畸力的下颌第一前磨牙用作对照组（CG）。
BG组和WG组的所有前磨牙在牙骨质和牙本质水平均显示ERR。在所有吸收区域均观察到牙骨质细胞的修复，但很少发现完全修复。BG组和WG组在ERR方面未发现统计学上的显著差异。牙根高度位置（中部或颈部三分之一）与ERR发生率之间未发现关联。与腭侧和邻面相比，颊侧牙根表面的ERR量更高。CG组的任何牙齿均未发现ERR。
所有接受RME的上颌第一前磨牙均显示ERR和部分牙骨质修复。带环牙齿的ERR并不比非带环支抗牙齿更多。
