Objective: To evaluate the amount and direction of skeletal, dental and soft tissue change after six weeks of intermaxillary fixation and after 15 months following mandibular set-back surgery in Class-III malocclusion.
Method: Seventeen patients with skeletal Class-III malocclusion were treated by presurgical orthodontics and mandibular set-back osteotomy. The study was carried-out on the lateral cephalograms of the patients taken before surgery, six weeks after surgery and 15 months after surgery. The amount and direction of skeletal, dental and soft tissue change was studied.
Results: Six weeks post-surgically ANB, WITTS, OP-MP (occlusal plane–mandibular plane) displayed significant increase and SNB showed significant decrease. Moreover lower incisors up righted and lower lip strain decreased significantly. Fifteen months after surgery we saw significant decrease in the value of witts appraisal. Similarly the distance between upper incisal point and labial superior decreased by 1.23 mm.
Conclusions: Although sagittal split osteotomy is a widely practiced procedure to correct Class-III malocclusions, however dental relapse in the form of maxillary proclination and significant retroclination of mandibular incisors is bound to occur. Similarly skeletal relapse in the form of mandibular anterior rotation cannot be prevented. Thus we have learnt the pattern of relapse in our population and the measures to minimize the relapse.