Related Experiment Video
Updated: Mar 11, 2026

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
Change in the vertical dimension of Class II Division 1 patients after use of cervical or high-pull headgear
Erin Dobbins Zervas1, Maria Therese S Galang-Boquiren2, Ales Obrez3
1Private practice, Louisville, Ky.
Introduction:
The goals of this study were to compare the effects that cervical and high-pull headgear have on the vertical dimensions in Class II Division 1 patients during phase 1 treatment and to compare these effects with untreated predicted growth for the sample population.
Methods:
Pretreatment and posttreatment cephalometric radiographs of children who had undergone Class II Division 1 correction with cervical (n = 22) or high-pull headgear (n = 19) were analyzed for the measurements that describe the changes in the vertical component of growth and mandibular position. The groups were matched for age (mean, 9 ± 2.5 years), treatment time (mean, 14 months), malocclusion, and similar skeletal features. The groups were compared with each other and also with an untreated growth model.
Results:
Treatment with cervical headgear resulted in smaller increases in measurements that describe the vertical dimension than with high-pull headgear. Cervical headgear showed more favorable changes in mandibular growth that were statistically significant when compared with the untreated growth models.
Conclusions:
In this study, the cervical headgear showed more control over the vertical dimension and produced more favorable changes in mandibular position by normalizing the occlusal plane. Compared with the untreated growth model, cervical headgear worked synergistically with growth to produce more optimal changes in mandibular position.
Related Concept Videos
General Case of Eccentric Axial Loading
Consider a member subjected to equal and opposite forces that are applied along a line that does not coincide with the member's neutral axis. In unsymmetrical...
Vertebral Column: Regions and Curvature
Regions of the Vertebral Column
In an adult, the spine is subdivided into five regions: the cervical, the thoracic, the lumbar, the sacral, and the coccygeal region. The spine initially develops as a series of 33 vertebrae; after 20 years of age, the nine bones in the sacral region, five sacral, and four coccygeal bones fuse to form...
Cardiopulmonary Resuscitation II: ACLS Airway Management

