A Perioral Soft Tissue evaluation after Orthognathic Surgery Using Three-Dimensional Computed Tomography Scan.

Background: Facial appearance is an important factor, affects social and psychological well-being. The ideal positioning of jaws and soft tissues is crucial during orthognathic surgery for a better outcome, but the response of facial soft tissues does not always reflect the exact movements of the underlying jaws in 1:1 ratio. So, soft tissue changes following orthognathic surgery require utmost attention during surgical correction to make successful treatment.

Aims and Objectives: Evaluation of perioral soft tissue changes after orthognathic surgical procedures. The objectives of the study were to assess and compare pre and post-operative perioral soft tissue changes of lip width, nasolabial and mentolabial angle using Three Dimensional Computed Tomography scan (3DCT).

Patient and Methods: The study involved ten patients for evaluation requiring orthognathic surgical procedures (maxillary or mandibular anteroposterior excess or deficiency, transverse deformities, vertical maxillary excess and facial asymmetry) presented to the department of oral and maxillofacial surgery during 2014-2016. Pre and post-operative 3DCT scan were taken after 12 months using iCT 256 slice whole body CT scanner and evaluated for changes using Dicom PMS D view.

Results: Significant changes were observed in nasolabial angle after maxillary advancement (1.81°) and maxillary setback procedure (2.73°). The mentolabial angle was significantly increased with mandibular setback procedures (3.27°). Mandibular advancement procedures showed both increase (3.6°) and decrease (7.6°) in mentolabial angle.

Conclusion: 3DCT showed a significant difference in perioral soft tissue changes in nasolabial and mentolabial angle but no significant change was observed in lip width. 3DCT is a reliable tool for 3D assessment. The conventional thought of changes in Nasolabial angle after surgery is changing due to the underlying factors which should be considered for prediction.