The Spatial Relationship Between Coronoid Process and Zygomatic Complex After Reduction Malarplasty.

BACKGROUND: Reduction malarplasty presents challenges in terms of postoperative complications, particularly limited mouth opening. Excessive inward displacement of the zygomatic complex can impinge on the coronoid process resulting in restricted mouth opening. This study aimed to assess the spatial relationship between the coronoid process and the zygomatic complex after reduction malarplasty. METHODS: A retrospective study was conducted, including consecutive patients underwent reduction malarplasty. Radiological measurements were performed before surgery and during the final follow-up, including the coronoid-condylar index, distance between the coronoid process and zygomatic complex, and thickness and density of the temporal and masseter muscles. Clinical and radiographic data were recorded and analyzed. RESULTS: A total of 159 female patients were included with an average age of 28.1 years and a mean follow-up of 6.7 months. The mean coronoid-condylar index was 1:1.4, ranging from 1:0.6 to 1:2.6. Following surgery, the distances between the coronoid process and the anterior zygoma decreased by approximately 1 mm. Additionally, the postoperative distance between the highest point of the coronoid process and the zygomatic arch decreased by around 4 mm horizontally and changed approximately 1 mm vertically. No significant changes were observed in the thickness and density of the temporal and masseter muscles after surgery. CONCLUSIONS: Reduction malarplasty led to a slight decrease in the distance between the coronoid process and the zygoma. The operation generally resulted in proximity between the highest point of the coronoid process and the zygomatic arch. However, we believe that common reduction malarplasty rarely leads to osseous impingement. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Repairing Cranial Defect With Autogenous Mandibular Outer Plate.

BACKGROUND: Autogenous bone is the best material in cranioplasty because of biological advantages. Previously, skull, rib, ilium, and fibula have been used in the reconstruction of cranial defects. However, the application of autologous mandibular outer plate in the treatment of skull defect is rarely reported. This study evaluated the application of the autogenous mandibular outer plate in the reconstruction of cranial defect. METHODS: Eleven patients who underwent cranioplasty with mandibular outer plate were recruited. Three-dimensional tomography data were collected to calculate the preoperative, immediate postoperative, and long-term follow-up volume of the bone graft area and donor bone site, and then the absorption rate and the regeneration rate of autogenous bone were analyzed. RESULTS: The majority of the patients were satisfied with the reconstructive outcome. There are statistical differences in the volumetric measurements of the bone graft area and bone donor site at different time periods (P<0.05). The mean absorptivity of mandibular outer plate implanted in the cranial defect area was (17.30 ±â€Š5.03)% after 3 to 24 months postoperatively, the average regeneration rate of mandibular outer plate volume was (41.65 ±â€Š9.85)% at the same period. CONCLUSION: This report shows that the cranioplasty with mandibular outer plate bone graft may be an optional surgical procedure.

An Effective Simulator for Intraoral Facial Skeletal Contour Surgeries.

BACKGROUND: In East Asia, intraoral facial skeletal contour surgeries (intraoral FSCSs), including reduction gonioplasty, reduction malarplasty, and genioplasty, have become increasingly popular. Nonetheless, intraoral FSCSs are technically difficult and have a steep learning curve. An effective simulator could be beneficial for intraoral FSCS training. However, there is no intraoral FSCS simulator available. We introduced an intraoral FSCS simulator and assessed its effectiveness. METHODS: An intraoral FSCS simulator was established by covering a 3-dimensional printed skull with elastic cloth. Twenty residents were enrolled and randomly divided into experimental group A and control group B. Group A performed the intraoral FSCS on the simulator for 3 times. Group B performed the intraoral FSCS on skull model for 3 times. The intraoral FSCS simulator and trainees' performance were evaluated by a trainee-reported questionnaire before and after training, the surgical outcomes were graded by 3 senior attending physicians. All questions and the surgical outcome were scored based on a 5-point Likert scale (1 = very poor, 5 = very good). The surgical times were recorded. RESULTS: The intraoral FSCS simulator (4.13 ± 0.64) simulated the surgical reality significantly better than the skull (2.6 ± 0.63). In intraoral FSCS simulator training, the restriction and compliance of the facial soft tissue were vividly mimicked (4.4 ± 0.51); the intraoral approach was vividly mimicked (4.07 ± 0.59). The intraoral FSCS simulator is significantly superior to the skull in improving participants' confidence in performing intraoral FSCS, power system control, and intraoral approach adoption (<0.001). The average surgical outcome score was 3.11 ± 0.45 in group A and 3.91 ± 0.24 in group B. The average surgical time was 177.78 ± 28.38 minutes in group A and 65.26 ± 15.38 minutes in group B. CONCLUSIONS: We developed the first intraoral FSCS simulator and proved its effectiveness preliminarily. Randomized controlled study with clinical cases is needed to further test its effectiveness.

Mandibular Augmentation With a New Sandwich Osteotomy: A Morphologic Study.

OBJECTIVE: Facial asymmetry is one of common complaints in plastic and craniofacial surgery in Orient. Hemimandibular dysplasia has considered to be the key role in facial asymmetry. Despite of the undergrow of mandibular length and height, the lackness of mandibular thickness contributes to the asymmetry. The aim of this study was to describe the therapeutic efficiency of mandibular augmentation with a new sandwich osteotomy with interpositional natural coral and coralline hydroxyapatite (CHA). METHODS: Nine goats were randomly divided into 3 groups and observed at 6, 12, and 18 months after surgery. All goats received splitting of bilateral mandibular outer cortex and interpositional grafting with natural coral and CHA, respectively (sandwich osteotomy). Data were evaluated and statistically analyzed by t-test. RESULTS: All goats were observed at 3 different time points. The computed tomography images show that the area of operation was healed and the thickness of the mandible was increased in 3 time points. In the 3 groups, mandibular thickness and volume were significantly different compared with those before operation (P < 0.05). The volume of CHA group improved better than coral group (P < 0.05). CONCLUSION: This study provides a promising alternative method for mandibular augmentation with a sandwich osteotomy and interpositional grafting with natural coral and CHA. The thickness and volume of mandible had been effectively increased in follow-ups.

Three-Dimensional Analysis of Mandibular Angle Classification and Aesthetic Evaluation of the Lower Face in Chinese Female Adults.

BACKGROUND: Reduction gonioplasty is very popular in East Asia. However, there has been little quantitative criteria for mandibular angle classification or aesthetics. The aim of this study was to investigate the quantitative differences of mandibular angle types and determine the morphologic features of mandibular angle in attractive women. METHODS: We created a database of skull computed tomography and standardized frontal and lateral photographs of 96 Chinese female adults. Mandibular angle was classified into 3 groups, namely, extraversion, introversion, and healthy group, based on the position of gonion. We used a 5-point Likert scale to quantify attractiveness based on photographs. Those who scored 4 or higher were defined as attractive women. Three types of computed tomography measurements of the mandible were taken, including 4 distances, 4 angles, and 3 proportions. Discriminant analysis was applied to establish a mathematic model for mandibular angle aesthetics evaluation. RESULTS: Significant differences were observed between the different types of mandibular angle in lower facial width (Gol-Gor), mandibular angle (Co-Go-Me), and gonion divergence angle (Gol-Me-Gor) (P < 0.01). Chinese attractive women had a mandibular angle of 123.913 ± 2.989 degrees, a FH-MP of 27.033 ± 2.695 degrees, and a Go-Me/Co-Go index of 2.0. The "healthy" women had a mandibular angle of 116.402 ± 5.373 degrees, a FH-MP of 19.556 ± 5.999 degrees, and a Go-Me/Co-Go index of 1.6. The estimated Fisher linear discriminant function for the identification of attractive women was as follows: Y = -0.1516X1(Co-Go) + 0.128X2(Go-Me) + 0.04936X3(Co-Go-Me) +0.0218X4(FH-MP). CONCLUSIONS: Our study quantified the differences of mandibular angle types and identified the morphological features of mandibular angle in attractive Chinese female adults. Our results could assist plastic surgeons in presurgical designing of new aesthetic gonion and help to evaluate lower face aesthetics.

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 patient's 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 ±â€Š2.79 mm preoperative and 35.67 ±â€Š3.39 mm at the latest follow-up. The mean distraction distance was 16.17 ±â€Š5.98 mm. The body mass index improved from 17.33 ±â€Š0.64 kg/m preoperative to 18.75 ±â€Š0.60 kg/m 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.

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 ±â€Š0.50%. The average MOC thickness accuracy at the preop MSBAP is 3.36 ±â€Š1.13%. The average MOC volume accuracy is 3.41 ±â€Š1.37%. The average percentage volume maintenance of fat grafting is 62.79 ±â€Š5.73%. 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.

Reduction Gonioplasty: Bone Regeneration and Soft Tissue Response.

BACKGROUND: Reduction 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. METHODS: We 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. RESULTS: Bone 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). CONCLUSIONS: Bone 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.

Surgical Template to Minimize the Damage of Tooth Buds in Young Children With Mandibular Distraction Osteogenesis.

BACKGROUND: Mandibular distraction osteogenesis has become one of the most powerful reconstructive techniques for the treatment of mandibular deformities in young children. Damage to the tooth buds is often cited as a complication of it. The purpose of this study was to precisely design the osteotomy line and avoid the damage of tooth buds at the mandibular angle area with the help of surgical template. METHODS: Six patients aged from 6 to 10 years were selected in this study. Three-dimensional computed tomography data was put into Mimics software for preoperative planning the osteotomy line and the accurate placement of the distractor based on the exact position of tooth follicle. And then the surgical template was manufactured by a three-dimensional printer with rapid prototyping technique. The surgeons were guided to perform the osteotomy aided with the prefabricated template through an intraoral approach. Distraction began 7 days postoperation with a rate of 1 mm/d and the distractor was removed after a 6 to 8 months consolidation period. The tooth buds were observed through radiographs that were performed at 5 time intervals: before distraction, at the end of latency, at the end of distraction, at the end of consolidation and 2 years of the postoperation to remove the distractor. RESULTS: The average follow-up time is 24 months. Facial appearance and occlusal plane of all the young patients were greatly improved without complications. From the radiological observation, the tooth buds was intact after the surgery and the second molar normally erupted after removing the distractor. CONCLUSIONS: The surgical template was considered to be helpful in improving the surgical accuracy and avoiding the tooth buds damage during mandibular distraction osteogenesis.

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.

Zygomatic Complex Change After Reduction Malarplasty and Its Geometric Model: A Retrospective Clinical Study.

PURPOSE: To achieve optimal outcomes in reduction malarplasty, the amount of removed zygomatic bone must be planned accurately. This study aimed to analyze the associations between the width of bony resection and changes in zygomatic bony parameters, to propose a geometric model to guide surgical planning, and to objectively evaluate the surgical outcomes of reduction malarplasty based on computed tomographic (CT) images. PATIENTS AND METHODS: This was a retrospective observational study of patients who underwent reduction malarplasty. Digitized CT images were used to evaluate the bony parameters of the zygomatic complex. A geometric model was proposed to guide surgical planning for malar reduction. The primary predictor variable was the width of the bony segment to be resected. The primary outcome variables were changes in malar prominence and attractiveness. Other variables included gender, age, and other bony parameters of the zygoma. Bivariate correlation analysis and multiple linear regression analyses were performed between predictor and outcome variables. Presurgical and postsurgical data were analyzed with paired-samples t test to evaluate surgical outcomes. Differences were considered statistically significant at a P value less than .05. RESULTS: Fifty-one patients who underwent reduction malarplasty with an L-shaped osteotomy from 2012 through 2014 were included in the study. Statistical analysis showed a significant decrease in malar prominence and increased attractiveness between presurgical and postsurgical images (P < .001). The width of bony resection was statistically associated with all outcome variables after adjusting for potential confounders. CONCLUSIONS: Reduction malarplasty with a modified L-shaped osteotomy resulted in a notable decrease in malar prominence and a statistical decrease in the zygomatic arch width. The amount of bone that must be removed from the zygoma to achieve a desired reduction can be calculated with geometric equations. The proposed methodology could assist surgical design and improve surgical accuracy.

Computer-assisted design of sequential surgical procedure for oblique facial clefts with mandibular outer cortex autografts.

BACKGROUND: Oblique facial clefts are congenital craniofacial malformations affecting the paramedian line of facial structures. Correction of these defects involves bone and soft tissue reconstruction. The authors have developed a computer-aided sequential surgical procedure for oblique facial clefts, including mandibular outer cortex autografting, medial canthal ligament reduction and fixation, and fat autografting. METHODS: From 2004 to 2013, 12 patients (9 women, 3 men) with oblique facial clefts were treated with the 3-step procedure in our clinic. Mean patient age at the first surgery was 18 years (range, 13-25 years). Preoperative three-dimensional surgical simulations assisted the surgeries. A retrospective review of patients' clinical, photographic, and radiographic records was performed. RESULTS: All patients achieved significant treatment effects and high satisfaction. The patients' self-assessed scores on a 10-point scale of deformity severity were lower after surgery (P < 0.001) and remained stable after 6 to 12 months (P = 0.069). Good repositioning of the inner canthus was achieved (P < 0.001) with no significant relapse (P = 0.096). The mean (SD) recovery of mandibular donor sites was 48.44% (16.89%) (range, 11.03%-71.33%). Grafted bone absorption was not significantly different at different recipient sites. Only minor complications occurred in 6 patients. CONCLUSIONS: This procedure was an effective treatment for oblique facial clefts, resulting in high satisfaction, remarkable improvements in facial symmetry, little skin scarring, acceptable bone graft resorption, and dramatic recovery of mandibular donor sites. Computer-assisted surgical simulation effectively describes characteristic skeletal deformities and provides a useful guide to surgical reconstruction.

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

UNLABELLED: 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. METHOD: Ten consecutive patients underwent mandibular chinbody osteotomy used silicone triangle template technique. Patient and surgeon's satisfaction of the surgery and surgeon's confidence improvement with template during the surgery were measured. RESULT: All patients and surgeons were satisfied with the outcome. The operator's confidence was significantly improved during the operation. CONCLUSIONS: Silicone triangle template technique is an effective method to achieve highly symmetrical mandibular chin-body osteotomy and boost surgeon's confidence.

Unilateral zygomatic hypoplasia correction by L-shaped zygomatic osteotomy with natural coral.

PURPOSE: Zygomatic osteotomy is a common method of zygomatic hypoplasia correction. Natural coral is considered to be a good bone substitute. Few studies on unilateral zygomatic hypoplasia correction by zygomatic osteotomy with natural coral have been reported. This study was performed to evaluate the clinical morphological results and surgical outcomes of unilateral zygomatic hypoplasia correction by L-shaped zygomatic osteotomy with natural coral. METHODS: From 1996 to 2012, a total of 42 patients with hypoplastic zygomas treated by L-shaped zygomatic osteotomy with natural coral were included in this study. Based on facial analysis results and x-ray and CT measurements, the degradation of natural coral, new bone formation, and clinical outcomes were observed and recorded. RESULTS: All surgical procedures achieved satisfactory results without complications. During the stabilization period of about 12 to 15 months, all natural coral blocks were completely degraded and replaced by new bone. Good mechanical strength and continuity of the new bone and good zygomatic asymmetry were achieved in each patient. No recurrence was observed during the follow-up period. CONCLUSION: L-shaped zygomatic osteotomy with natural coral is an effective method of unilateral zygomatic hypoplasia correction.

Three-dimensional preoperative design of distraction osteogenesis for hemifacial microsomia.

The purpose of this research was to simulate mandibular movement calculated from three-dimensional computed tomography (CT) data to determine the linear distractor position to correct mandibular deformities in a series of patients with hemifacial microsomia (HFM). Preoperative CT scans from 6 HFM patients were obtained and imported into a CT-based software program (Mimics) to produce three-dimensional images and data. After measurement of the mandibular deficiency in 3 dimensions (horizontal and vertical), the angle between the distraction device and the ramus was determined by a geometric calculation, and then the surgery was performed on the three-dimensional model constructed using the rapid prototyping technique. This planning method was finally used in the treatment of 6 HFM patients. The HFM was corrected, and a symmetrical facial contour obtained without any complications in these 6 patients. The results matched the expectation before surgery that the distractor elongation would range from 18 to 22 mm. The distraction tracing model fitted the actual postdistraction tracing to within 2 mm. The preoperative design and three-dimensional modeling technique are considered to be helpful in enhancing the predictability and improving the outcome of the treatment of distraction osteogenesis.

Titanium screw entered into maxillary sinus: a rare incident during rigid fixation of the porous polyethylene implant in enophthalmos correction.

Screw fixation is used for accurate augmentation by porous polyethylene implant in traumatic enophthalmos correction to avoid complications such as migration and protrusion. We report an incident of titanium screw entered into the maxillary sinus during enophthalmos correction with porous polyethylene implant. Such incident could be avoided by standard manipulation. We here present the rare case and offer proposals for the screw fixation of porous polyethylene implant during traumatic enophthalmos correction.

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

UNLABELLED: 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.

Strategy to minimize oral mucosal tear and lip injury in facial contouring and orthognathic surgery.

In this article, the authors present a simple but effective technical strategy to protect the lip and mucosa from iatrogenic thermal injury and traumatic mucosal tear in orthognathic and aesthetic facial contouring surgery. During surgical exposure and osteotomy, a piece of double-layered Vaseline dressing gauze is strategically placed over the lip and mucosal tissues before the application of the Obwegeser or Gimma retractors. The objective is to avoid traumatic and thermal injury to the lip and mucosal tissues during the use of various retractors and other craniomaxillofacial dynamic instruments in such surgery. In our experience of consecutive 400 intraoral osteotomy procedures over the last 5 years of using the double-layered Vaseline gauze to protect the lip tissues and oral mucosa, there was no incidence of any unintentional complications of thermal injury and tears of the lip and mucosa. It is simple and effective with minimum learning curve, but most importantly it has significantly minimized the morbidity associated with lip thermal injury and mucosal tear in these patients.

Treatment protocol and surgical techniques for macrogenia.

BACKGROUND: This study focused on the treatment protocol for macrogenia and surgical techniques of the semicircular ostectomy of the mandibular inferior border. METHODS: Seven patients with macrogenia were treated following our treatment protocol including a preoperative assessment (the Delaire analysis), an operative design (three-dimensional reconstruction and simulation), operation techniques (semicircular ostectomy of the mandibular inferior border), and a postoperative evaluation. RESULTS: Our treatment procedure provided an overall harmonizing effect on the lower facial contour. All 7 patients were satisfied with their aesthetic results. A few complications such as numbness and submental soft-tissue excess were observed, but they improved to different extent as time went by. CONCLUSIONS: Our treatment protocol for macrogenia is of great use to make the surgeries to be precisely and safely done with satisfactory results.