A Comparative Assessment of Occlusal Bite Force Changes After Surgical Correction of the Increased Vertical Dimension in Mandibular Prognathism Subjects: A Prospective Clinical Trial

Forty-two patients who presented to orthodontic clinics with severe Class III skeletal malocclusion and were already into orthodontic preparation for orthognathic surgery were selected to participate in thestudy.

Patients were allocated into one of 2 groups as follows: - Group 1: - Class III patients with increased vertical relationship Included 22 patients (8 males, 14 females).These patients were scheduled for bimaxillary surgical procedures (Maxillary advancement and mandibular setback with posterior maxillary impaction) to correct the antero-posterior and vertical skeletal discrepancies.

Group 2: - Class III subjects with normal vertical relationship Included 20 patients (8 males, 12 females).These patients were scheduled for mandibular setback surgical procedure (with no posterior maxillary impaction) to correct the antero-posterior skeletal discrepancy.

Diagnostic records (orthopantomogram, lateral cephalogram, study casts, clinical photographs) were taken for all subjects before surgery. The same records were taken post surgery just before fixed orthodontic appliance debond.

The included patients were treated by orthodontic teaching staff and postgraduate residents at orthodontic clinics/JUST using pre-adjusted edgewise fixed appliance (3M Gemini Uniteks, 0.022" MBT prescription brackets).