Long-term three-dimensional condylar remodeling during presurgical orthodontics and after orthognathic surgery of mandibular retrognathia with high mandibular plane angle.

OBJECTIVES: Patients with high mandibular plane facial morphology are the most dominant facial type who experience TMJ abnormalities with resultant condylar resorption, affecting the orthodontic and orthognathic treatment outcomes. The study aimed to quantitatively assess the three-dimensional condylar remodeling during the presurgical orthodontics and after orthognathic surgery of the retrognathic mandible with a high mandibular plane angle. The study also investigated the correlation between the resultant remodeling based on the hypothesis that condylar resorption following orthognathic surgery is a part of a progressive presurgical resorption process. MATERIALS AND METHODS: The study included adults with mandibular retrognathism and high mandibular plane angle who have computed tomography scans (CT) obtained before any treatment (T0), after completion of presurgical treatment before surgery (T1), and at long-term follow-up after surgery (T2). DICOM of CT scan was gathered and processed using ITK-SNAP and 3D Slicer software. The interval between T0 and T1 was represented as a presurgical phase, while between T1 and T2 was defined as a postsurgical phase (T1-T2). RESULTS: Twenty-five patients (50 condyles) were included with a mean age of 23 ± 3.2 years. The mean of the follow-up during the presurgical phase was 19.8 ± 7.1 months and 15.5 ± 5.5 months during the postsurgical phase. The condylar volume during the presurgical phase (T0-T1) was relatively stable (- 3.3 ± 37.2mm3). However, during the postsurgical phase (T1-T2), the volume was significantly reduced - 113.8 ± 98.3mm3 (P < 0.001). Localized condylar surface resorption during the postsurgical phase was significantly higher than during the presurgical phase (P < 0.05). No correlation was found between the localized condylar surface remodeling during the presurgical and postsurgical phases. However, a negative statistically significant correlation existed between the overall condylar volume changes during the presurgical and postsurgical phases (r = 0.502, P < 0.001). CONCLUSION: Significant condylar resorption following orthognathic surgery of the retrognathic mandible with a high mandibular plane angle might occur regardless of the presurgical status of the condyle. CLINICAL RELEVANCE: The study provided an evidence to be discussed with the patients and considered throughout the treatment of mandibular retrognathia with high mandibular plane angle.

Factors to Consider When Deciding on the Type of Free-Flap Reconstruction of Head and Neck Soft Tissue Defects.

OBJECTIVES: The aim of the study was to evaluate the functional and aesthetic outcomes on donor and recipient sites and to determine the effects of technical factors including flap thickness and vessel diameters measured by ultrasonography as well as the size of the defect and postoperative volume reduction of the flaps measured by magnetic resonance imaging (MRI). METHODS: In patients who had undergone soft tissue reconstructive surgery between March 2013 and March 2016 using 55 anterolateral thigh flaps (ALTFs), 30 radial forearm flaps (RFFs), and 18 latissimus dorsi flaps (LDFs), color Doppler ultrasonography was performed to measure the thickness of the flap at the site of the perforator. Preoperative color Doppler ultrasound examinations of the blood vessel diameters of donor and recipient sites were carried out. RESULTS: 97.1% of flaps showed complete survival and 2.9% complete failure (2 ALTFs and 1 LDF). The difference in flap volume of ALTFs, RFFs, and LDFs between MRI 1 (3-6 weeks) and MRI 2 (6-18 months) was 27.6, 17.9, and 36.1%, respectively. CONCLUSION: Proper selection of the flap is important for the optimization of the aesthetic and functional outcomes. Ultrasound, the surgeon's experience and the extension and nature of the defect play a key role in the selection of the flap.