Synthesis of the New-Type Vascular Endothelial Growth Factor-Silk Fibroin-Chitosan Three-Dimensional Scaffolds for Bone Tissue Engineering and In Vitro Evaluation.

The objective of the study was to discuss the biocompatibility of the vascular endothelial growth factor-silk fibroin-chitosan (VEGF-SF-CS) scaffolds. To offer an ideal scaffold for bone tissue engineering, the author added vascular endothelial growth factor (VEGF) into silk fibroin-chitosan (SF-CS) scaffold directly to reconstruct a three-dimensional scaffold for the first time, SF-CS scaffold was loaded with VEGF and evaluated as a growth factor-delivery device. Human fetal osteoblast cell was seeded on the VEGF-SF-CS scaffolds and SF-CS scaffolds. On VEGF-SF-CS and SF-CS scaffolds, the cell adhesion rate was increased as time went on. Scanning electron microscopy: the cells grew actively and had normal multiple fissions, granular and filamentous substrates could be seen around the cells, and cell microfilaments were closely connected with the scaffolds. The cells could not only show the attached growth on surfaces of the scaffolds, but also extend into the scaffolds. Cell Counting Kit-8 and alkaline phosphatase analysis proved that the VEGF could significantly promote human fetal osteoblast1.19 cells growth and proliferation in the SF-CS scaffolds, but the enhancement of osteoblasts cell proliferation and activity by VEGF was dependent on time.

Percutaneous Treatment of Large Venous Malformations in the Oral and Maxillofacial Regions Using Electrochemical Therapy Combined With Pingyangmycin.

PURPOSE: The aim of the present study was to evaluate the therapeutic outcome of using electrochemical therapy (ECT) combined with a sclerosing agent, pingyangmycin (bleomycin A5 hydrochloride; PYM), for large (>3 cm in diameter) venous malformations (VMs) in the oral and maxillofacial regions. PATIENTS AND METHODS: Thirty-five patients (15 male and 20 female; age range, 10 to 69 yr; mean age, 32 yr) with large VMs in the oral and maxillofacial region were treated with a combination of ECT and PYM under general anesthesia in the authors' department from June 2012 through May 2014. The size of the lesions varied from 3 × 3 to 12 × 15 cm. A repeated course of ECT and PYM was administered for larger VMs. The therapeutic interval was 3 months for ECT and 2 to 4 weeks for PYM. The dose of PYM for patients was 8 mg each time, and the injection concentration of PYM was 1.6 mg/mL. Patients were followed for 6 to 36 months. Therapeutic results were evaluated by clinical examination and Doppler ultrasonography before and after treatment. RESULTS: Of the 35 patients, 29 (82.9%) received 1 ECT treatment, 5 (14.3%) received 2 ECT treatments, and 1 (2.8%) received 3 ECT treatments. The number of PYM injection sessions was 1 to 5 (average, 2.5 times). According to the therapeutic criteria, the clinical outcome was excellent in 22 patients (62.9%), good in 10 patients (28.6%), and fair in 3 patients (8.5%). All patients (100%) had local swelling postoperatively that lasted approximately 1 to 2 weeks. Two patients (5.7%) had fever. No skin necrosis or nerve damage was found. CONCLUSIONS: Percutaneous treatment using ECT and PYM was a straightforward, safe, and reliable treatment modality for large VMs.

Reconstruction for facial nerve defects of zygomatic or marginal mandibular branches using upper buccal or cervical branches.

BACKGROUND: Many reconstructive methods for facial nerve defects have been described previously, such as the greater auricular nerve graft, the sural nerve graft, or hypoglossal-facial nerve anastomosis. Herein, we want to instruct a new technique of repairing facial nerve defects of zygomatic or marginal mandibular branches using upper buccal or cervical branches when we have to face segment defects of facial nerve with wide gaps between facial nerve stumps. METHODS: The distal part of the upper buccal or cervical branches with peripheral tissue was removed to repair the defects of zygomatic or marginal mandibular branches. Clinical and electromyographic examinations were employed to investigate the clinical efficacy of this method. RESULTS: Killed branches of facial nerve included 11 marginal mandibular branches and 16 zygomatic branches in 26 patients. The length of facial nerve defects ranged from 0.9 cm to 2.3 cm with a mean gap of 1.87 cm (SD, 0.89). Seventeen patients finally showed a superb facial function (grade I), 6 patients an excellent outcome (grade II), and 3 patients a good result (grade III). A fair or poor result (grade IV or V) was not observed. CONCLUSIONS: The essence of this method is equivalent to direct facial-facial nerve anastomosis which seems to be able to avoid synkinesis between the upper and lower face. We believe that this method is adaptable to the length of facial nerve defects less than 2 cm.

Anthropometric analysis of the maxillary bone and the alar base in unilateral cleft lip with secondary nasal deformity: classification of a piriform margin bony depression.

OBJECTIVES: This study was conducted to measure the soft tissue of the alar base and the piriform aperture area of the maxillary bone of unilateral cleft lips with secondary nasal deformities when secondary operation are necessary to classify the alar base depression and to provide a clinical reference for the second surgery. METHODS: Twenty-six patients with unilateral cleft lip with secondary nasal deformity were treated at the Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medial University. Nose data were attained preoperatively and postoperatively. Correlations were made between the soft tissue and the bony depression and patient satisfaction with the nasi basis. Classifications were then made based on these data. RESULTS: When the distance discrepancy of the bilateral piriform aperture depression was less than 4.5 mm, we obtained a fine appearance for the nose by repairing only the soft tissues. When it was more than 5 mm, we had to combine repair of the soft tissue with a bone graft or the restitution of the alveolar cleft. When the distance was between 4.5 mm and 5 mm, the surgeon considered both the wishes of the patient and the clinic's standard procedure. CONCLUSIONS: For patients with cleft lips and palates, the bony depression was not the only factor that resulted in postoperative alar depression. Anthropometry of the nose prior to surgery was important for choosing the methods that would yield satisfactory results.

Application of problem-based learning in a large class in stomatology course.

PURPOSE: To determine the feasibility of implementing problem-based learning (PBL) in a large class and whether previous PBL experience is necessary. MATERIALS AND METHODS: A total of 236 students from 2 large classes at China Medical University were enrolled. One class (118 students) had had a previous small-group PBL experience and another class (113 students) had not. Each class was subdivided into 15 groups (7 to 8 students/group) and took 2 separate 100-minute PBL sessions per week with the same teaching faculty. Each PBL class had 2 facilitators, 1 content expert facilitator, and 1 nonexpert facilitator. The results of the theoretical examination and case analysis examinations were analyzed using the t test. Questionnaires were used to evaluate both student and facilitator perceptions. RESULTS: The feedback from both students and facilitators was positive. According to the questionnaires, both experienced and non-experienced students acknowledged that the teaching method was enjoyable and functional. The test results showed students had achieved the learning objectives. The results of the theoretical and case analysis examinations showed no significant difference between the PBL experienced class and the non-experienced class. The mean study hours spent weekly by the students after class on the course were about 6.3 +/- 1.1 hours for the non-experienced students and 4.7 +/- 0.981 hours for the experienced students (t = 11.94, P < .001). The non-experienced students showed more preference for the content expert tutor. CONCLUSION: Implementing PBL in a large class is feasible without extracting great demand on limited educational resources. Previous PBL experience is helpful but not necessary.

Synthesis of and in vitro and in vivo evaluation of a novel TGF-ß1-SF-CS three-dimensional scaffold for bone tissue engineering.

The role of transforming growth factor-ß1 (TGF-ß1) in normal human fracture healing has been previously demonstrated. The objective of the present study was to examine the biocompatibility of TGF-ß1-silk fibroin-chitosan (TGF-ß1-SF-CS) three-dimensional (3D) scaffolds in order to construct an ideal scaffold for bone tissue engineering. We added TGF-ß1 directly to the SF-CS scaffold to construct a 3D scaffold for the first time, to the best of our knowledge, and performed evaluations to determine whether it may have potential applications as a growth factor delivery device. Bone marrow-derived mesenchymal stem cells (BMSCs) were seeded on the TGF-ß1-SF-CS scaffolds and the silk fibroin-chitosan (SF-CS) scaffolds. On the TGF-ß1­SF-CS and the SF-CS scaffolds, the cell adhesion rate increased in a time­dependent manner. Using a Cell Counting Kit-8 (CCK-8) assay and analyzing the alkaline phosphatase (ALP) expression proved that TGF-ß1 significantly enhanced the growth and proliferation of BMSCs on the SF-CS scaffolds in a time-dependent manner. To examine the in vivo biocompatibility and osteogenesis of the TGF-ß1­SF-CS scaffolds, the TGF-ß1-SF-CS scaffolds and the SF-CS scaffolds were implanted in rabbit mandibles and studied histologically and microradiographically. The 3D computed tomography (CT) scan and histological examinations of the samples showed that the TGF-ß1-SF-CS scaffolds exhibited good biocompatibility and extensive osteoconductivity with the host bone after 8 weeks. Moreover, the introduction of TGF-ß1 to the SF-CS scaffolds markedly enhanced the efficiency of new bone formation, and this was confirmed using bone mineral density (BMD) and biomechanical evaluation, particularly at 8 weeks after implantation. We demonstrated that the TGF-ß1­SF-CS scaffolds possessed as good biocompatibility and osteogenesis as the hybrid ones. Taken together, these findings indicate that the TGF-ß1-SF-CS scaffolds fulfilled the basic requirements of bone tissue engineering, and have the potential to be applied in orthopedic, reconstructive and maxillofacial surgery. Thus, TGF-ß1-SF-CS composite scaffolds represent a promising, novel type of scaffold for use in bone tissue engineering.

Construction and in vitro characterization of three-dimensional silk fibroinchitosan scaffolds.

The objective of this study was to discuss the construction method, characterization, and biocompatibility of three-dimensional silk fibroin-chitosan (SF-CS) scaffolds which met the requirements of bone tissue engineering scaffolds. Silk fibroin (SF) and chitosan (CS) were mixed at different ratios -3 to 7, 5 to 5, and 7 to 3- to fabricate the composite materials. To find out the optimum mixing ratio of SF and CS, parameters such as pore size, porosity, water absorption, and the mechanical properties were evaluated. Osteoblast cells hFOB1.19 were seeded on SF-CS scaffolds and pure CS scaffolds for the first time. Cell adhesion rate, cell proliferation, and cell activity were evaluated, and cell growth and formation of mineralized nodules were observed. Results showed that SF-CS scaffolds are a suitable candidate for bone tissue engineering.

A practical guide for diagnosis and treatment of arteriovenous malformations in the oral and maxillofacial region.

Arteriovenous malformations (AVMs) are congenital vascular malformations (CVMs) resulting from birth defects of the vasculature. It is rarely seen, only accounting for 1.5% of all vascular anomalies, and 50% of the lesions are located in the oral and maxillofacial region. Regardless of the type, AVMs may ultimately lead to significant anatomical, pathophysiological and hemodynamic consequences. Therefore, despite their relative rarity, AVMs still remain the most challenging and/or life-threatening form of vascular anomalies. Transarterial coil embolisation or ligation of feeding arteries are incorrect approaches and may result in progress of the lesion. Furthermore, such procedures would prevent future endovascular access to the lesions via the arterial route, and should be abandoned. Interventional embolisation using various sclerosants is currently the mainstay of treatment for AVMs, and elimination of the nidus (if present) is the key to success. Among various embolosclerotherapy agents, ethanol sclerotherapy produces the best long-term outcomes, with minimal complications. For more complex cases, multidisciplinary approaches and interventions may provide an excellent potential for a curative result. Based on the published literature and clinical experiences, a practical treatment guideline was established in order to provide a criterion for the management of oral and maxillofacial AVMs. This protocol will be renewed and updated to reflect cutting edge knowledge, and provide the newest treatment modalities for oral and maxillofacial AVMs.

[Intralesional pingyangmycin injection in the management of macrocystic lymphatic malformations in cervical region].

PURPOSE: To investigate the therapeutic effects of pingyangmycin injection as a primary therapy of macrocystic lymphatic malformations in cervical region. METHODS: Thirty-six patients with macrocystic lymphatic malformations in cervical region underwent the therapy of pingyangmycin injection between 2009 and 2012 at School of Stomatology, China Medical University. Among them, 16 patients had unilateral submandibular lesions, 20 patients had lesions in anterior cervical regions. The age of patients was from 6 months to 25 years old. The concentration of the drug was 1.6 mg /mL with an addition of lidocaine. The dose and cycle of treatment were dependent on the lesions' size and patients' age. The follow-up period was 12 months to 2 years after the last treatment. RESULTS: The total effective rate was 100%, and the curative rate was 94.4%. No serious complications were encountered. CONCLUSIONS: Intralesional Injection of pingyangmycin provides a safe and effective treatment for macrocystic lymphatic malformations in cervical region as a primary treatment.

[Clinical application of unimportant branches of facial nerve to repair important ones].

PURPOSE: To study the feasibility and clinical effect of repairing important branches of facial nerve (zygomatic and marginal mandibular branches) with unimportant ones (upper buccal and cervical branches). METHODS: The defect of zygomatic and marginal mandibular branches was repaired with upper buccal and cervical branches, respectively. After the length of facial nerve defect was measured, the distal part of the upper buccal and cervical branches with peripheral tissue was used to repair the defect. Under operating microscope, nerve anastomosis was performed with 9-0 suture. 5 cases suffering from defect of marginal mandibular branches were repaired with cervical branches, and 7 cases with defect of zygomatic branches were repaired with upper buccal branches. RESULTS: In 5 cases suffering from defect of marginal mandibular branches, 2 cases recovered in 3 months, and 3 cases recovered in 6 months; In 7 cases suffering from defect of zygomatic branches, all recovered in 3-4 months. CONCLUSION: Repair of defect of zygomatic and marginal mandibular branches with upper buccal and cervical branches is feasible and the result is acceptable.

[Application the sternocleidomastoid muscle-great auricular nerve flap in radical parotidectomy].

OBJECTIVE: To study a new method for repair of facial depression and facial nerve defect after parotid carcinoma resection. METHODS: 12 patients with parotid carcinoma and peripheral bone invasion were treated using facial nerve canal dissection and radical resection of the tumor, the parotid gland and the involved facial nerve and bone, including the mastoid, stylomastoid foramen, styloid process and the rear part of the mandible. A sternocleidomastoid muscle flap was elevated and transferred to repair the facial depression. The great annular nerve in the flap was anastomosed with the severed end of the facial nerve in the canal. RESULTS: The depressed deformity of the parotid area was well corrected in 9 patients. The aesthetic results were compromised in 2 patients because of tumor recurrence and reoperation. The depressed deformity was not corrected in 1 patient because of infection. Postoperatively, the function of the facial nerve recovered to a normal level. The recovery time ranged from 12 to 20 weeks ,with an average of 16.3 weeks. The local control rate of tumor was improved. CONCLUSIONS: Immediate transplantation of the sternocleidomastoid muscle-great auricular nerve flap and facial nerve canal dissection in radical parotidectomy can repair the depressed deformity of the parotid area, restore facial nerve function,and decrease tumor recurrence. The method is an ideal operation with functional recovery.