Xi Fu

A Novel Method of Mild to Moderate Parry-Romberg Syndrome Reconstruction: Computer-Assisted Surgery With Mandibular Outer Cortex and Fat Grafting.

Background: In patients with mild to moderate Parry–Romberg syndrome (PRS), plastic surgeons have mainly focused on the restoration of soft tissue deficiencies. While, bone deficits are easily overlooked. This study developed a new method combines the autologous mandibular outer cortex (MOC) grafting with fat grafting in mild to moderate patients with PRS, and apply computer-assisted techniques to improve the surgical outcomes and accuracy. Methods: Seven patients with mild to moderate PRS were prospectively enrolled in the study. Preoperative and 7 days and 6 months postoperative computed tomography (CT) and photographs were performed. Computer-aided design was done based on preoperative CT data. Surgical templates for MOC harvesting and grafting were designed and printed out. The topographic map of fat grafting was generated. The accuracy of MOC bone grafting was evaluated by the MOC thickness relative error, the MOC thickness accuracy at the preop most severe bone atrophy point (preop MSBAP), and the MOC volume accuracy. The percentage volume maintenance of the fat grafting surgery was assessed. Results: All 7 patients had ideal clinical outcomes with significant improvement in facial symmetry and no major complications happened. The average MOC thickness relative error is 2.85 ± 0.50%. The average MOC thickness accuracy at the preop MSBAP is 3.36 ± 1.13%. The average MOC volume accuracy is 3.41 ± 1.37%. The average percentage volume maintenance of fat grafting is 62.79 ± 5.73%. Conclusions: The combination of MOC grafting with fat grafting can be an excellent choice in reconstruction of mild to moderate patients with PRS. Applying computer-assisted techniques offers a reliable and accurate outcome.

Long-term changes in the masseter muscle following reduction gonioplasty.

&NA; Many plastic surgeons use mandibular osteotomy (reduction gonioplasty) without masseter resection to correct a square face. However, there is not enough long-term observation of the masseter after reduction gonioplasty, although some researches have already confirmed that the volume of masseter muscle does decrease shortly after reduction gonioplasty. Methods: The Plastic Surgery Hospital database was retrospectively reviewed for patients who underwent reduction gonioplasty. Fifty-six patients with both preoperative and 4 years postoperative 3-dimensional computed tomography (3DCT) were included. The changes in the volume and morphology of the masseter muscle after reduction gonioplasty were assessed quantitatively. The 3DCT data were analyzed using Mimics 10.01 software. Results: All patients were satisfied with the outcome. No complications happened. There were significant differences between the preoperative and 4 years postoperative volume and morphology. Conclusion: After reduction gonioplasty, the masseter muscle atrophied (reduced 20.98% ± 8.75%), especially the lower part of the masseter muscle in the long-term follow-up. Most patients with prominent mandibular angles should be treated with reduction gonioplasty without approaching the masseter muscle.

Reduction Gonioplasty: Bone Regeneration and Soft Tissue Response.

BackgroundReduction gonioplasty is frequently used to achieve an oval-shaped face in Asia. However, the soft tissue response and bone regeneration of reduction gonioplasty which are keys to the outcome are still unclear. The aim of this study is to evaluate the effects of bone regeneration on facial width and the soft tissue response of reduction gonioplasty. MethodsWe retrospectively reviewed patients who underwent reduction gonioplasty from 2009 to 2013. A high-speed rotary cutting bur without a water coolant was routinely used from the new gonial point to the inferior mandibular rim under the second premolar, whereas the elongated osteotomy line (mandibular-chin body osteotomy) was performed with a reciprocating saw. Forty-nine patients with preoperative, immediate postoperative, and 12-month postoperative frontal cephalograms were included in our study. Mandible and soft tissue profiles were measured on cephalograms. ResultsBone regeneration in high-speed rotary cutting bur ostectomy region was −0.79 ± 1.76 mm (1 cm above Go-Go), −0.75 ± 1.46 mm (Go-Go, bigonial line), and −0.77 ± 2.10 mm (1 cm below Go-Go), whereas 0.07 ± 1.79 mm (2 cm below Go-Go) in ostectomy region performed by reciprocating saw. The soft tissue response ratios were 76.72 ± 30.70% (Go-Go), 108.8 ± 54.11% (1 cm below Go-Go), and 155.9 ± 66.82% (2 cm below Go-Go). ConclusionsBone regeneration does not lead to an increase in facial width after reduction gonioplasty with our technique, and the use of a high-speed rotary cutting bur without a water coolant decreases bone regeneration. The soft tissue response ratio is higher in the anterior mandible, and the outcome of reduction gonioplasty is a sharper lower face with a full cheek. Reduction gonioplasty is an effective and predictable lower face reshaping surgery.

Interpositional Arthroplasty by Temporalis Fascia Flap and Galea Aponeurotica Combined With Distraction Osteogenesis: a Modified Method in Treatment of Adult Patients With Temporomandibular Joint Ankylosis and Mandibular Dysplasia

Background: Interpositional arthroplasty (IPA) with temporalis fascia flap has been one of the most frequently performed procedures to treat temporomandibular joint (TMJ) ankylosis. However, recurrence often occurs when the flap lacks bulk or atrophies. Whether to perform IPA or distraction osteogenesis (DO) first has long been a controversial issue when patients presented mandibular dysplasia (MD). This study provided IPA a new graft material sufficient to prevent recurrence, combined the modified protocol of performing DO 6 months after IPA, and evaluated its efficacy in treating TMJ ankylosis patients with MD. Methods: Six patients with unilateral TMJ ankylosis and MD were treated in the authors’ study. The temporalis fascia flap and part of adjacent galea aponeurotica were filled the space after surgical release. Mouth-opening exercises started immediately post-IPA. Distraction osteogenesis was performed 6 months after IPA and had a 4-month consolidation. The maximum interincisal distance at preoperative, immediately post-IPA and the latest follow-up were recorded, as was the distraction length. The body mass index was measured at each patients postoperative visit. Result: All patients had significant improvements in facial aesthetic, mouth-opening, and occlusion. No major complication or recurrence was observed at 3 to 4 years’ follow-up. The mean maximum interincisal distance was 4.83 ± 2.79 mm preoperative and 35.67 ± 3.39 mm at the latest follow-up. The mean distraction distance was 16.17 ± 5.98 mm. The body mass index improved from 17.33 ± 0.64 kg/m2 preoperative to 18.75 ± 0.60 kg/m2 before DO. Conclusions: Temporalis fascia flap and adjacent galea aponeurotica as new graft materials are recommended for IPA. The modified staged treatment proved to be reliable and effective to prevent recurrence, improve mandibular length and final occlusion.

Standardized Protocol for Virtual Surgical Plan and 3-Dimensional Surgical Template–Assisted Single-Stage Mandible Contour Surgery

Background Mandible contour surgery, including reduction gonioplasty and genioplasty, has become increasingly popular in East Asia. However, it is technically challenging and, hence, leads to a long learning curve and high complication rates and often needs secondary revisions. The increasing use of 3-dimensional (3D) technology makes accurate single-stage mandible contour surgery with minimum complication rates possible with a virtual surgical plan (VSP) and 3-D surgical templates. This study is to establish a standardized protocol for VSP and 3-D surgical templates–assisted mandible contour surgery and evaluate the accuracy of the protocol. Methods In this study, we enrolled 20 patients for mandible contour surgery. Our protocol is to perform VSP based on 3-D computed tomography data. Then, design and 3-D print surgical templates based on preoperative VSP. The accuracy of the method was analyzed by 3-D comparison of VSP and postoperative results using detailed computer analysis. Result All patients had symmetric, natural osteotomy lines and satisfactory facial ratios in a single-stage operation. The average relative error of VSP and postoperative result on the entire skull was 0.41 ± 0.13 mm. The average new left gonial error was 0.43 ± 0.77 mm. The average new right gonial error was 0.45 ± 0.69 mm. The average pognion error was 0.79 ± 1.21 mm. Patients were very satisfied with the aesthetic results. Surgeons were very satisfied with the performance of surgical templates to facilitate the operation. Conclusions Our standardized protocol of VSP and 3-D printed surgical templates–assisted single-stage mandible contour surgery results in accurate, safe, and predictable outcome in a single stage.

Abstract: Standardized Protocol for Visual Surgical Plan and Three Dimensional Surgical Template-Assisted Single-Stage Mandible Contour Surgery

BACKGROUND: Mandible contour surgery, such as reduction gonioplasty and genioplasty, has become increasingly popular in East Asia. However, it is technically challenging, and hence, leads to a long learning curve, high complication rates, and often needs secondary revisions. The increasing use of three-dimensional (3D) technology makes accurate single stage mandible contour surgery with minimum complication rates possible with a virtual surgical plan (VSP) and 3D surgical templates. This study is to establish a standardized protocol for VSP and 3D surgical templates-assisted mandible contour surgery and evaluate the accuracy of the protocol.

Computer Image-Guided Template for Horizontal Advancement Genioplasty.

Background:Horizontal advancement genioplasty can be extremely rewarding for microgenia. However, it is challenging for even very experienced surgeon to determine the three-dimensional position of the distant bone fragment during the operation. This study aimed to apply and evaluate computer-aided design (CAD) and computer-aided manufacturing techniques for horizontal advancement genioplasty to improve surgical accuracy. Methods:Seven patients with microgenia were prospectively enrolled in the study. Preoperative and postoperative computed tomography (CT), photographs, and lateral cephalograms were performed. Computer-aided design was done based on preoperative CT data, and then surgical templates (cutting guide templates and fixation templates) were designed accordingly to guide horizontal advancement genioplasty. All surgeries were performed by junior surgeons. The accuracy of the authors’ method was evaluated by the relative error (the mean value of discrepancy between postoperative CT and preoperative design at 6 points selected randomly/preoperative design movement × 100%), Pg position error (postoperative Pg Advancement – preoperative CAD Pg Advancement)/preoperative CAD Pg Advancement × 100%), and Me position error (postoperative Me downward movement − preoperative CAD Me downward movement)/preoperative CAD Me downward movement × 100%). They are all calculated by Geomagic automatically. Results:All 7 patients were satisfied with their aesthetic outcomes. The average absolute relative error is 1.8%. The average absolute Pg position error is 1.9% and the average absolute Me position error value is 1.3%. Conclusions:The authors’ study showed that applying computer-assisted techniques for horizontal advancement genioplasty provided accurate surgical result. With this technique, best result for horizontal advancement genioplasty could be achieved by even inexperienced surgeons.

A Novel Method to Attain Highly Symmetric Oblique Mandibular Chin-Body Osteotomy.

Oblique mandibular chin-body osteotomy is a widely used narrowing genioplasty. However, the historic challenge is how to achieve a highly symmetric result of oblique mandibular chin-body osteotomy. Here, we present a novel and simple method to achieve a highly symmetrical mandibular chin-body osteotomy.