Buccal Lipoma Detected Postoperatively in a Case with Facial Asymmetry.

Introduction: Facial asymmetry has been one of the important themes in jaw deformities.The course of treatment for jaw deformities is usually decided in response to cephalometrical analysis, but it is difficult to suspect the movement of soft tissue after surgery. In this paper, asymmetry, caused by the buccal lipoma discovered postoperatively, is discussed.Case: A seventeen-year-old female visited Hamamatsu University Hospital in 1991 with maxillary retrusion, mandibular protrusion, and facial asymmetry diagnosed cephalometrically. After preoperative orthodontic treatment, Le Fort I osteotomy and ramus sagital split osteotomy were carried out in September 1993. After surgery the cephalometrical asymmetry was improved, but her cheek remained swollen. The excess tissues of the cheek, especially the right buccal fat pad, was thought to be the cause because there were no other abnormal findings such as induration. Then the buccal fat pad was partially removed when the miniplates were removed. However, the facial asymmetry of soft tissue was not improved. After taking a CT and an MRI, the right buccal lipoma with capsule was found. In March 1996, the lipoma was resected, and as a result, her facial asymmetry was corrected.Discussion: Facial asymmetry is caused by hard tissue and/or soft tissue. In consideration of the incidence of asymmetry among the jaw deformities and the incidence of lipoma in the maxillofacial area, such as this case, soft tissue tumors such as lipoma are thought to be possible causes of facial asymmetry. When evaluating facial asymmetry, especially in cases of facial asymmetry of soft tissue remaining postoperatively, an image diagnosis such as a CT or an MRI should be utilized.Conclusion: Since soft tissue tumors such as lipoma are possible causes of facial asymmetry, facial asymmetry should be examined carefully.