Tae Geon Kwon

Does Skeletal Surgery for Asymmetric Mandibular Prognathism Influence the Soft Tissue Contour and Thickness

PURPOSE The purpose of the present study was to investigate whether asymmetric mandibular prognathism accompanies a fundamental difference in soft tissue thickness and whether asymmetric mandibular setback surgery would influence the contour and thickness of the soft tissue of the chin. MATERIALS AND METHODS The present retrospective study included skeletal class III patients with significant mandibular chin deviation greater than 6 mm at the pogonion, who had undergone cone-beam computed tomography before and 6 months after surgery during a 2-year period. The predictor variables were timing (pre- and postoperatively) and side (asymmetric vs contralateral). The outcome measures were the hard and soft tissue contours and soft tissue thickness of the chin at the infradentale, B-point, and pogonion level evaluated with reformatted computed tomography images. The study variables were statistically compared using regression model and correlation analysis. RESULTS The present study consisted of 20 patients (10 males and 10 females; average age 20.2 years; range, 18 to 25). Preoperatively, the chin deviation side showed a more prominent hard and soft tissue outline but had a thinner soft tissue thickness, which camouflaged the hard tissue asymmetry. After surgery, the hard and soft tissue outline was greatly improved, and the soft tissue thickness had become nearly symmetric. Most of the soft tissue thickness changes correlated negatively with the hard tissue changes. CONCLUSIONS Asymmetric mandibular prognathism accompanied the 3-dimensional soft tissue contour and thickness asymmetry. Because the soft tissue responds favorably after skeletal surgery, the correction of 3-dimensional asymmetry of bone should be emphasized in patients with asymmetric mandibular prognathism.

Inflammatory granuloma caused by injectable soft tissue filler (Artecoll).

Artecoll (Artes Medical Inc., San Diego, CA, USA) has recently been developed as a permanent synthetic cosmetic filler. We experienced an inflammatory granuloma resulting from a previous injection of Artecoll at the upper lip, which was regarded as a rare side effect of this filler. A 50-year-old female patient complained of swelling, dull pain, and heat in the right upper nasolabial fold area, which had started one week before her visit to Kyungpook National University Hospital. The patient received topical steroid therapy at a local clinic, which was not effective. At the injection site, a hard nodule was palpated and erythema was observed with mild tenderness. Antibiotic treatment and subsequent incision and drainage did not result in complete cure of the facial swelling, and the facial swelling and pain persisted. Computed tomography showed a lesion approximately 1-cm in size without clear boundaries and relatively increased nodular thickening. Finally, a subdermal lesion was removed via an intraoral vestibular approach. The lesion was diagnosed as inflammatory granuloma by a permanent biopsy. The patient had healed at two months after the filler injection. Although the soft tissue filler is widely used for cosmetic purposes, there is potential for complication, such as the inflammatory granuloma should be considered before treatment.

Evaluation of Pterygomaxillary Anatomy Using Computed Tomography: Are There Any Structural Variations in Cleft Patients?

PURPOSE Structural characteristics of the pterygomaxillary region in patients with cleft lip and palate (CLP) have not been fully investigated. This study aimed to evaluate the regional anatomy of the pterygomaxillary junction of patients with CLP using computed tomography. MATERIALS AND METHODS The pterygomaxillary structures of patients with unilateral or bilateral CLP were compared with those of a control group using axial computed tomography. The thickness and width of the pterygoid plate, the distance from the greater palatine foramen to the lateral pterygomaxillary junction, the lateral and medial pterygoid plate lengths, and the maxillary posterior transverse width were investigated with axial computed tomography just beneath the level of the inferior nasal concha and approximately 3 to 5 mm above the nasal floor. The difference between the cleft and noncleft sides or the right and left sides of each group and the measurement differences between the groups were statistically compared. RESULTS The study group was composed of 14 patients with unilateral CLP and 6 with bilateral CLP, and the control group were 20 age- and gender-matched patients with skeletal Class III without CLP. Patients with unilateral CLP and those with bilateral CLP were statistically equivalent for all radiographic variables. In patients with CLP, the width of the pterygomaxillary region and the greater palatine foramen region were on average 1.5 to 1.8 mm larger than in control patients (P < .05). Lateral pterygoid plate length and maxillary posterior transverse width were similar in the 2 groups. However, the patients with CLP showed a 2.3-mm shorter medial pterygoid length (P < .05). CONCLUSION Patients with CLP had larger and thicker pterygomaxillary dimensions, and the results imply that careful attention to pterygomaxillary anatomy is needed in patients with CLP undergoing Le Fort I surgery.

Reconstruction plates used in the surgery for mandibular discontinuity defect

Objectives The purpose of this study was to analyze the survival rate of reconstruction plates that were used to correct mandibular discontinuity defects. Materials and Methods We analyzed clinical and radiological data of 36 patients. Only discontinuous mandibular defect cases were included in the study. Reconstruction plate survival rate was analyzed according to age, gender, location of defect, defect size, and whether the patient underwent a bone graft procedure, coronoidectomy, and/or postoperative radiation therapy (RT). Results Plate-related complications developed in 8 patients, 7 of which underwent plate removal. No significant differences were found in plate survival rate according to age, gender, location of defect, defect size, or whether a bone graft procedure was performed. However, there were differences in the plate survival rate that depended on whether the patient underwent coronoidectomy or postoperative RT. In the early stages (9.25±5.10 months), plate fracture was the most common complication, but in the later stages (35.75±17.00 months), screw loosening was the most common complication. Conclusion It is important to establish the time-related risk of complications such as plate fracture or screw loosening. Coronoidectomy should be considered in most cases to prevent complications. Postoperative RT can affect the survival rate and hazard rate after a reconstruction plate is fitted.