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Randomized Controlled Trial
. 2021 Sep;25(9):5247-5256.
doi: 10.1007/s00784-021-03832-9. Epub 2021 Feb 12.

Maxillary dentoskeletal outcomes of the expander with differential opening and the fan-type expander: a randomized controlled trial

Camila Massaro  1 , Daniela Garib  2 , Lucia Cevidanes  3 , Guilherme Janson  4 , Marilia Yatabe  3 , José Roberto Pereira Lauris  5 , Antonio Carlos Ruellas  3   6
Affiliations
Randomized Controlled Trial

Maxillary dentoskeletal outcomes of the expander with differential opening and the fan-type expander: a randomized controlled trial

Camila Massaro et al. Clin Oral Investig. 2021 Sep.

Abstract

Objectives: 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).

Material and methods: 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).

Results: 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.

Conclusions: 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.

Clinical relevance: 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.

Trial registration: The trial was registered at ClinicalTrials.gov , under the identifier NCT03705871.

Keywords: Imaging, three-dimensional; Orthodontic appliances; Orthodontics, interceptive; Palatal expansion technique.

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Conflict of interest statement

Conflict of interest Licensed patent of the expander with differential opening (PI 1101050–9) was registered by the second author (DG), São Paulo Research Foundation (FAPESP) and University of São Paulo at the National Institute of Industrial Property (INPIBrazil).

Figures

Fig. 1
Fig. 1
Expander with differential opening (a–d) and fan-type expander (e–h)
Fig. 2
Fig. 2
Three-dimensional models illustrating the pre-labelled landmarks. Right and left orbitales (OrR and OrL), placed at the lowest point in the inferior margin of the right and left orbitals; right and left zygomatic bones (ZygR and ZygL), placed at the most inferior portion of the right and left zygomatic bones; right and left nasal cavity (NCR and NCL), placed at the most inferior and external point of the concavity of the right and left nasal cavity; right and left palatine foramen (PFR and PFL), placed at the middle and most inferior point of the right and left palatine foramen; right and left apex of the mesial root of the maxillary first permanent molars (M′R and M′L); right and left root apex of the maxillary deciduous canines (C′R and C′L); right and left cusp tip of the mesiobuccal cusp of the maxillary first permanent molars (MR and ML); right and left cusp tip of the maxillary deciduous canines (CR and CL); posterior nasal spine (PNS) and anterior nasal spine (ANS)
Fig. 3
Fig. 3
Cranial base superimposition of the pre- (white) and post- (red) expansion 3-dimensional surface models in an anterior, lateral, and inferior view of a patient treated with the expander with differential opening
Fig. 4
Fig. 4
Cranial base superimposition of the pre- (white) and post- (green) expansion 3-dimensional surface models in an anterior, lateral, and inferior view of a patient treated with the fan-type expander
See this image and copyright information in PMC

References

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