Introduction
malocclusion
[version 1; peer review: 3 approvedNo competing interests were disclosed.




The efficacy of the chin cup in controlling mandibular growth remains a controversial matter.
Previously, mandibular adaptation to chin cup force has been evaluated using two-dimensional (2D) lateral cephalograms or panoramic radiographs. However, the information provided by these techniques is limited in evaluating the condyles and mandibular ramus.
Histologically, experimental animal studies have demonstrated a reduction in the width of the prechondroblastic zone and a decrease in the cellularity of the condylar head after chin cup therapy.
To our knowledge, no study has investigated the volumetric changes of the mandible and condyles after early chin cup therapy. This randomized controlled trial aimed to evaluate the changes in the mandible, condyles, and glenoid fossa following the chincup therapy of Class III malocclusion patients in comparison with those changes in a control group of untreated patients. It aimed to test the null hypotheses that no significant differences existed between the chincup and the control group concerning the changes in the mandible, the condyles, and the glenoid fossa.