Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil.
Department of Orthodontics, Bauru Dental School and Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil.
Clin Oral Investig. 2021 Sep;25(9):5247-5256. doi: 10.1007/s00784-021-03832-9. Epub 2021 Feb 12.
The aim of this study was to compare the maxillary dentoskeletal outcomes of the expander with differential opening (EDO) and the fan-type expander (FE).
Forty-eight patients with maxillary arch constriction in the mixed dentition were randomly allocated into EDO and FE groups. Cone-beam computed tomography scans were acquired before and after expansion. Linear and angular three-dimensional changes were assessed after cranial base superimposition using the ITK-SNAP and the 3D Slicer software. T or Mann-Whitney U tests were used for intergroup comparisons (P<0.05).
The EDO group comprised 24 patients treated with the EDO (13 female, 11 male; 7.6 years). The FE group comprised 24 patients treated with the FE (14 female, 10 male; 7.8 years). Skeletal lateral displacements were greater in the EDO group with greater expansion in the orbital, nasal cavity, zygomatic bone, and palate regions (mean intergroup differences of 0.4, 0.8, 0.9, and 1.1 mm, respectively). Intercanine expansion and canine buccal inclination were greater in the FE group, while intermolar distance changes and molar buccal inclination were greater in the EDO group. Similar changes were observed for vertical and anteroposterior displacements and palatal plane rotation.
The EDO produced greater transverse skeletal expansion compared to the FE, with similar vertical and anteroposterior effects. Dental changes were greater in the molar region for patients treated with the EDO and in the canine region for patients treated with the FE.
The EDO and the FE are capable of producing skeletal changes in the mixed dentition. The decision between both expanders will depend on the amount of expansion required in the molar region and in the nasomaxillary complex.
The trial was registered at ClinicalTrials.gov , under the identifier NCT03705871.
本研究旨在比较扩弓器（EDO）和扇形扩弓器（FE）对上颌牙颌骨结构的影响。
48 例混合牙列期上颌牙弓狭窄患者随机分为 EDO 组和 FE 组。扩弓前后均行锥形束 CT 扫描。采用 ITK-SNAP 和 3D Slicer 软件进行颅底叠加后，评估三维线性和角度变化。采用 T 检验或 Mann-Whitney U 检验进行组间比较（P<0.05）。
EDO 组 24 例患者，接受 EDO 治疗（女性 13 例，男性 11 例；年龄 7.6 岁）。FE 组 24 例患者，接受 FE 治疗（女性 14 例，男性 10 例；年龄 7.8 岁）。EDO 组的上颌骨侧向移位较大，眶区、鼻腔区、颧骨区和上颌区的扩张程度也较大（组间平均差异分别为 0.4、0.8、0.9 和 1.1mm）。FE 组的尖牙间宽度增加和尖牙颊倾度较大，而 EDO 组的磨牙间距离增加和磨牙颊倾度较大。垂直和前后向位移以及腭平面旋转也观察到类似的变化。
与 FE 相比，EDO 可产生更大的横向骨骼扩张，同时对垂直和前后向也有相似的效果。接受 EDO 治疗的患者磨牙区和接受 FE 治疗的患者尖牙区的牙性变化较大。
EDO 和 FE 均可在上颌混合牙列期产生骨骼变化。两种扩弓器的选择将取决于磨牙区和鼻上颌复合体所需的扩张量。
该试验在 ClinicalTrials.gov 注册，标识符为 NCT03705871。
