An interventional study of Tooth-Borne Expander with Facemask (FM) and Hybrid Skeletal Anchorage Expander with Chin-Plate (SA) in Skeletal Class III Malocclusion, sponsored by Universidad Complutense de Madrid. Not yet recruiting. Open to participants aged Up to 18 Years. Per ClinicalTrials.gov, last updated 2026-02-03.
Sponsored by Universidad Complutense de Madrid · Not applicable, Interventional, and Treatment
This retrospective non-randomized controlled clinical trial aimed to compare the skeletal and dentoalveolar effects of two orthopedic treatment protocols for skeletal Class III malocclusion in growing patients: a conventional tooth-borne rapid maxillary expansion combined with facemask therapy, and a hybrid skeletal anchorage expander combined with chin-plate traction. Lateral cephalometric changes before and after maxillary protraction were analyzed to assess sagittal skeletal correction and dentoalveolar effects.
Skeletal Class III malocclusion is frequently associated with maxillary growth deficiency and presents significant functional and esthetic challenges. Conventional treatment using rapid maxillary expansion combined with facemask therapy is effective but limited by patient compliance and undesirable dentoalveolar effects. The introduction of skeletal anchorage devices allows the application of orthopedic forces with reduced dental compensation and extended effectiveness beyond early growth stages.
This study retrospectively evaluated growing patients (CVS1-CVS3) treated with either a tooth-borne expander and facemask or a hybrid skeletal anchorage expander combined with chin-plate traction. Cephalometric variables were measured before treatment (T0) and after completion of maxillary protraction (T1) to compare skeletal and dentoalveolar changes between protocols.
57 studies on the registry are indexed under Malocclusion, Angle Class III; 11 are open to participants now.
This study's planned enrollment of 36 is above the median of 32 across 53 interventional studies indexed under Malocclusion, Angle Class III.
Browse Malocclusion, Angle Class III studies →Universidad Complutense de Madrid is the lead sponsor of 206 studies on the registry; 64 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria
Bonded acrylic splint-type Hyrax expander with hooks in the maxillary canine region. Expansion activated once daily (0.25 mm). Facemask therapy initiated two weeks after expansion onset with 400 g per side of elastic traction, directed approximately 30° downward relative to the occlusal plane, worn 14-16 hours per day.
Device: Tooth-Borne Expander with Facemask (FM)
Modified Hybrid Hyrax expander supported by first molars and anchored with miniscrews placed bilaterally in a paramedian position. Expansion activated once daily (0.25 mm). Mandibular chin-plates (bollard-type or single chin-plate depending on eruption stage) were surgically inserted, and Class III elastics delivering 400 g per side were applied following a progressive loading protocol.
Device: Hybrid Skeletal Anchorage Expander with Chin-Plate (SA)
Bonded acrylic splint-type Hyrax expander with hooks in the maxillary canine region. Expansion activated once daily (0.25 mm). Facemask therapy initiated two weeks after expansion onset with 400 g per side of elastic traction, directed approximately 30° downward relative to the occlusal plane, worn 14-16 hours per day.
Modified Hybrid Hyrax expander supported by first molars and anchored with miniscrews placed bilaterally in a paramedian position. Expansion activated once daily (0.25 mm). Mandibular chin-plates (bollard-type or single chin-plate depending on eruption stage) were surgically inserted, and Class III elastics delivering 400 g per side were applied following a progressive loading protocol.
Change in sagittal skeletal relationship
Changes in the cephalometric angles SNA, ANB, and Wits appraisal measured on lateral cephalograms between T0 and T1
Time frame: From baseline (T0) through study completion, an average of 1 year (T1)
Cephalometric vertical skeletal changes
o Cephalometric vertical measurements from T0 to T1, using a customized cephalometric analysis based on Steiner, Tweed, and McNamara references: Mandibular plane to SN (Sella-Nasion) angle, ANS (Anterior Nasal Spine)-PNS (Posterior Nasal Spine) to Mandibular plane angle, and ANS-PNS to SN angle
Time frame: From baseline (T0) through study completion, an average of 1 year (T1)
Cephalometric dentoalveolar changes
o Upper and lower incisor inclination changes from T0 to T1 using a customized cephalometric analysis based on Steiner, Tweed, and McNamara references: U\_SN (Upper incisor to Sella-Nasion)and IMPA (Lower Incisor Mandibular Plane Angle)
Time frame: From baseline (T0) through study completion, an average of 1 year (T1)
Treatment duration
o Time elapsed between T0 and T1
Time frame: From baseline (T0) through study completion, an average of 1 year (T1)
No study locations are listed for this record.
Plan to share: Undecided — Upon request
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Malocclusion, Angle Class III →
Universidad Complutense de Madrid →