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Analysis of the Dentoskeletal Effects of the Expander With Differential Opening

Analysis of the Dentoskeletal Effects of the Expander With Differential Opening: a Randomized Clinical Trial

Status
UNKNOWN
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02810353
Enrollment
50
Registered
2016-06-22
Start date
2015-05-31
Completion date
2018-02-28
Last updated
2016-06-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Bilateral Posterior Crossbite, Mandibular Dental Arch Constriction, Maxillary Constriction, Unilateral Posterior Crossbite

Brief summary

This study evaluates the dentoskeletal effects of the expander with differential opening in orthodontic patients in the mixed dentition. Half of participants will undergo rapid maxillary expansion (RME) using the expander with differential opening, while the other half will undergo RME using the conventional Hyrax expander.

Detailed description

Recently, a rapid maxillary expander with differential opening was developed aiming to treat maxillary constrictions greater in the anterior region compared to the posterior region of the maxillary dental arch. The aim of this study is to evaluate the dentoskeletal effects of the expander with differential opening in orthodontic patients in the mixed dentition. Material and methods: Fifty patients with maxillary constriction in the mixed dentition will be prospectively and randomly allocated in one of two study groups. The experimental group will comprise 25 patients who will be submitted to rapid maxillary expansion with the expander with differential opening. The control group will be comprised by 25 individuals who will undergo rapid maxillary expander with the Hyrax expander. Digital dental models will be acquired immediately pre-expansion (T1) and six months post-expansion (T2). The Orthoanalyzer™ software will be used to measure maxillary and mandibular widths, arches perimeter, arches lengths, palatal depth, and inclinations of maxillary and mandibular canines and permanent first molars. The intergroup and interphase comparisons will be analyzed using t tests and paired t tests, respectively (p\<0.05).

Interventions

DEVICEDifferential rapid maxillary expansion

Twenty-five patients will be submitted to rapid maxillary expansion using the expander with differential opening. Appliance anchorage will be provided by bands adapted either on the maxillary first permanent molars or on the second deciduous molars and circumferential clamps will be bonded to the maxillary deciduous canines. If the maxillary second deciduous molars will be banded, a lingual extension wire will be placed in the partially erupted maxillary first permanent molars. Both anterior and posterior screws will be activated with a complete turn a day during 6 days. Then, only the anterior screw will be additionally activated for 4 more days. After the active period of RME, the screws will be fixed with acrylic resin and the appliance will be kept as a retainer for 6 months.

Twenty-five patients will undergo rapid maxillary expansion using conventional Hyrax expander. Bands will be adapted either on the maxillary first permanent molars or on second deciduous molars and circumferential clamps will be bonded to the maxillary deciduous canines. Similarly to the experimental group, a lingual extension wire will be placed in the partially erupted maxillary first permanent molars if the maxillary second deciduous molars will be banded. The expander screw will be activated with a complete turn a day during 6 days. After the expansion active phase, the screw will be fixed with acrylic resin and the appliance will be kept in the dental arch as a retainer for 6 months.

Sponsors

University of Sao Paulo
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
7 Years to 11 Years
Healthy volunteers
No

Inclusion criteria

* Both sexes; * Ages ranging from 7 to 11 years old; * Mixed dentition; * Maxillary constriction; * No previous orthodontic treatment.

Exclusion criteria

* Cleft lip and palate and associated syndromes; * Systemic and/or neurological diseases.

Design outcomes

Primary

MeasureTime frame
Amount of interincisor diastema10 days
Maxillary and mandibular inter-first permanent molar distances6 months
Maxillary and mandibular inter-second deciduous molar distances6 months
Maxillary and mandibular inter-first deciduous molar distances6 months
Maxillary and mandibular inter-deciduous canine distances6 months
Maxillary and mandibular dental arches perimeters6 months
Maxillary and mandibular dental arches lengths6 months
Palatal depth6 months
Inclination of maxillary and mandibular first permanent molars6 months
Inclination of maxillary and mandibular deciduous canines6 months

Secondary

MeasureTime frame
Amount of differential expansion on the maxillary and mandibular dental arches6 months

Countries

Brazil

Contacts

Primary ContactArthur Alves, DDS, MSc
arthurcesar_88@hotmail.com+55 14 981060878

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026