Prediction of Profile changes Following Orthognathic Surgery in Cleft Patients

Objective: To evaluate dentoskeletal and soft tissue changes following maxillary advancement and mandibular setback in cleft patients and to study the relations between the hard and soft tissue changes so that profile changes after two jaw surgery could be predicted. Method: The prospective study was undertaken on 25 cleft patients (17 female, 8 males) aged 18-29 years. All had skeletal class III malocclusion with anterior cross bite. Pre-surgical orthodontic treatment and bone grafting were prescribed before surgery. Le Fort I maxillary advancement and mandibular setback with intraoral sagittal split osteotomies were performed by the two surgeons. The alterations of hard and soft tissue changes were analyzed from the lateral head films at 1 week before surgery and at least 6 months after surgery. Displacement of the reference points were evaluated by means of X-Y coordinate system in relation to the SN plane of the first film. Significant displacements of each reference point were analyzed by student paired t test at .05 significant level, relation of hard and soft tissue changes was analyzed by Pearson product moment correlation and prediction equations of significant soft tissue changes were attempted by stepwise regression analysis. Result: The study indicated facial improvement after surgery due to significant advancement of the maxilla and backward movement of the mandible. Forward movement of the A point was a good predictor of the subspinale whereas anterior movement of the upper incisors and posterior movement of the B point were good predictors for upper lip protrusion. Posterior movement of the lower incisors and bony chin were good predictors of the lower lip and chin improvement. Prediction equations for soft tissue alterations were presented. Conclusion: conventional Le Fort I osteotomy in conjunction with bilateral sagittal split osteotomies is a treatment option for cleft patients with severe skeletal class III malocclusion.