One-Year Relapse of Mandibular Distraction for Hemifacial Microsomia Using Masseteric Botulinum Toxin Type A Injections.

BACKGROUND: The relapse of hemifacial microsomia was thought to be highly related to the soft tissue envelope around the mandible angle mainly composed by masseter and medial pterygoid. According to the reason, we tried to apply masseter injection of type A botulinum toxin to weaken the soft envelope tension on the early stage post mandible distraction in adult HFM patients. METHODS: Eight patients diagnosed with HFM were studied and randomly assigned to an experimental or control group. Patients in the experimental group were treated with DO, orthognathic surgeries, autologous fat grafting, and bilateral masseter muscle injection with type A botulinum toxin. The patients in control group were treated with the same procedures as the patients in experimental group except for masseter muscle injection with type A botulinum toxin. The recurrence rates of both groups were evaluated and analyzed after nearly 1 year of follow-up. RESULTS: The mean recurrence rate was 26.30% ±â€Š11.84% (range 7.62%-37.27%) in the 8 patients after 1-year follow-up. The relapse rate was 16.32% ±â€Š7.78% (7.62%-26.22%) in the experimental group and 36.28% ±â€Š1.03% (34.84%-37.27%) in the control group. There was a significant difference (P = 0.002) between the experimental group and the control group. CONCLUSIONS: The combination of DO, orthognathic surgeries, autologous fat particle transplantation, and masseter muscle type A botulinum toxin injection technique could be a comprehensive treatment plan for adult patients of HFM. Furthermore, masseter injection of type A botulinum toxin might be an alternative method to reduce the early recurrence rate of postoperative adult patients of HFM.

Mandibular distraction combined with orthognathic techniques for the correction of severe adult mandibular hypoplasia.

BACKGROUND: Mandibular hypoplasia may result from congenital deformities or trauma or infection during the early stage of facial skeleton development. Deficiencies in the growth of the mandible can not only cause various degrees of facial deformity but also affect breathing and occlusal function. Here, we report our experiences with mandibular distraction combined with orthognathic surgical techniques for the treatment of severe adult mandibular hypoplasia. METHODS: Cephalometric analysis was conducted in all patients for quantitative evaluation. A computer-assisted surgical simulation was prepared before distraction. According to the simulation data, an operative osteotomy guide plate was designed and three-dimensionally printed with photosensitive resin. With the help of the guide plate, the osteotomy line was precisely placed. An internal distractor was then placed through an extraoral incision created under general anesthesia. Distraction began after 7 days of latency at the rate of 1 mm/d. After a 6- to 8-month consolidation period, the distractor was removed. At the same time, genioplasty and/or subapical osteotomy was performed to correct the patient's crossbite and improve the facial contour for bilateral mandibular hypoplasia. For unilateral mandibular hypoplasia, a Le Fort I osteotomy was performed to correct the open bite on the affected side, whereas a mandibular outer cortex excision was performed on the unaffected side to improve lower facial symmetry. RESULTS: The mandible symmetry and chin protrusion were efficiently improved in all 36 patients (mean age, 20.3 y). No facial nerve palsy was reported, nor were there complaints about postoperative facial scarring. The postoperative infection rate was 2.8%. The distance of lengthening was 26.2 (2.8) mm. The increased ramus length on the affected side was 18.9 (9.3) mm. At the end of the consolidation period (T2), the affected mandibular ramus length increased by 46.3% (23.6%) in unilateral distraction osteogenesis; however, it decreased by 18.6% (12.4%) after device removal (T3). For bilateral distraction osteogenesis, condylion-gonion increased by 34.0% (50.0%) in T2 but had no significant change in T3. CONCLUSION: Complicated mandibular hypoplasia can be well corrected with mandibular distraction combined with orthognathic surgery.

Accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant.

We report a rare case of accident entry of titanium screw into the sphenoid sinus during paranasal augmentation with porous polyethylene implant. The screw was finally retrieved from the sphenoid sinus by a nasal endoscope. We emphasize that, on this surgery region, the simple fixation skill must be performed delicately. Otherwise, an adverse event may still happen.

Pyrite-embedded porous carbon nanocatalysts assembled in polyvinylidene difluoride membrane for organic pollutant oxidation.

FeS2-embedded in porous carbon (FeS2/C) was prepared by simultaneous sulfidation and carbonization of an iron-based metal-organic framework precursor, and subsequently immobilized in polyvinylidene fluoride membranes (FeS2/C@PVDF) for organics removal via peroxymonosulfate (PMS) activation. The composition, structure, and morphology of the FeS2/C@PVDF membrane were extensively characterized. Scanning electron microscopy images manifest that the FeS2/C nanoparticles with an average diameter of 40 nm are assembled on the external and internal membrane surface. The as-prepared FeS2/C@PVDF membrane exhibits excellent performances over a wide pH range of 1.53-9.50, exceeding carbon-free syn-FeS2@PVDF. The effective degradation could be improved by inner pyrite FeS2 cores and thus enhanced the electron transfer between carbon shell and PMS. Electron paramagnetic resonance and quenching experiments elucidated that radical (HO∙, SO4∙-) and nonradical (1O2) species were the predominant reactive oxidants. In addition, FeS2/C@PVDF exhibited high stability with low Fe leaching (0.377 mg/L) owing to the effective protection of the outer carbon skeleton. Plentiful porosity of PVDF membranes not only affords a controlled size and confined uniform distribution of the immobilized FeS2/C nanoparticles, but also enables a persistent exposure of active sites and enhanced mass transfer efficiency. Our findings demonstrate a promise for utilizing the novel FeS2/C@PVDF membrane as an efficient catalyst for the environmental cleanup.

Incidents of Mandibular Distraction Osteogenesis for Hemifacial Microsomia.

BACKGROUND: This study focused mainly on the safety and unexpected incidents of mandibular distraction osteogenesis in treating patients with hemifacial microsomia. METHODS: Records of 71 patients with hemifacial microsomia treated by mandibular distraction osteogenesis from February of 2010 to March of 2015 were examined in this retrospective study. The modified mandibular osteotomy was conducted under the assistance of three-dimensional reconstruction, computer-aided design, and rapid prototyping technique. Distraction was conducted 4 to 7 days postoperatively at a frequency of 1 mm/day; moreover, the distractor was kept in place for 4 to 13 months after the first operation before it was removed. The scope of distraction ranged from 20 to 40 mm. All incidents encountered during and after the mandibular distraction process were documented in the medical records of patients. The patients were followed up for an average of 34.4 months after the second-stage operation. RESULTS: The overall rate of incidents was 36.6 percent. Of them, minor incidents, which could be resolved with or without noninvasive therapy, were observed in 18.3 percent of all procedures in this series. Meanwhile, the rate of moderate incidents necessitating invasive therapy was reported to be 12.7 percent, whereas that of major incidents that could not be resolved with invasive therapy was 5.6 percent. CONCLUSIONS: Mandibular distraction osteogenesis is a widely used procedure for treating patients with hemifacial microsomia. It is extremely important to be fully aware of a variety of incidents occurring during and after the surgical procedure to minimize the frequency of occurrence of such incidents. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

[The effect of mandibular distraction on the maxilla growth in children with hemifacial microsomia].

OBJECTIVE: To analyze the effect of mandibular distraction on the maxilla growth in children with hemifacial microsomia through measurement with the posterior-anterior cephalometric X-ray films and Three-dimensional CT reconstruction images. METHODS: The deviation angular of maxilla occlusion plane and nasal base plane from the infra-orbital plane were measured on the posterior-anterior cephalometric X-ray films in 22 patients before and half a year after operation. The vertical distance from the midpoint of 5th teeth alveolar and the lowest point of maxillary sinus to reference plane were measured on 3D reconstruction images in 15 patients. The data were statistically analyzed. RESULTS: On posterior-anterior cephalometric X-ray films, the cant of occlusion plane were significantly reduced (P < 0.05), While the angular of nasal base plane and the infra-orbital plane had no significant change. On 3D reconstruction images, all the detection points had significantly declined except the lowest point of maxillary sinus on normal side. CONCLUSIONS: Distraction osteogenesis of mandible can promote the growth of the maxilla in children with HFM, the accelerated growth parts include alveolar bone and maxillary sinus.

[Mandibular distraction combined with orthognathic techniques for the correction of adult hemifacial microsomia].

OBJECTIVE: To study the combination of Mandibular distraction and orthognathic techniques for the reconstruction of adult hemifacial microsomia. METHODS: The three-dimensional CT reconstruction data was used with Mimics for preoperation design. The osteotomy location, distraction vector, distraction distance were decided before operation with a surgical guider. At the first stage, internal distractor was implanted after ostetomy through an extra-oral approach. The distraction begun 5-7 days after operation with a frequency of 1 mm/day. After distraction, the distractor was maintained for 3-6 months. At the second stage, the distractor was removed. Le Fort I osteotomy was performed in order to correct the cross-bite and improve the facial contour. Usually, bone graft was inserted into the gap after Le Fort I osteotomy. The genioplasty was also performed if necessary. RESULTS: 9 cases of adult hemifacial microsomia with severe mandibular deviation were treated. The facial asymmetry were improved greatly. 1 patient suffered an wound infection in the maxillary region after Le Fort I osteotomy and healed uneventfully with wound irrigation. CONCLUSIONS: Mandibular distraction combined with orthognathic surgery is an effective procedure for adult hemifacial microsomia with complicated mandibular hypoplasia.

[Skeleton and soft tissue contour reconstruction for severe progressive hemifacial atrophy].

OBJECTIVE: To sum up the various procedures for skeleton and soft tissue contour reconstruction in severe progressive hemifacial atrophy. METHODS: From Jan 2004 to May 2012, 25 patients with severe progressive hemifacial atrophy underwent the procedures of lipoinjection, microsurgical flap transplantation, dermis grafting, distraction osteogenesis, orthognathic surgery and so on for both skeleton and soft tissue reconstruction. RESULTS: Among them, zygomatic augmentation and lipoinjection were performed in 24 cases, anterolateral thigh adipofascial flap in 10 cases and latissimus dorsi flap in one case, orthognathic surgery in 17 cases, including Le Fort I osetoectomy in 3 cases, genioplasty in 4 cases, mandibular distraction osteogenesis combined with secondary Le Fort I osteotomy in 3 cases, genioplasty combined with mandibular augmentation with Medpor implant in 7 cases. The patients were followed up for 6 months to 5 years. Through skelton and soft tissue reconstruction, the oblique occlusion plane and malocclusion were corrected with great improvement in face asymmetry. CONCLUSIONS: For severe progreassive hemifacial atrophy, comprehensive procedures should be adopted for both skelton and soft tissue reconstruction to achieve good results.