Head and Neck Soft Tissue Sarcoma Patient: Age and Tumor Region Are Predictive in Disease-Free Survival and Overall Survival.

BACKGROUND: Head and neck soft tissue sarcoma (HNSTS), rare and heterogeneous malignancies, are treated primarily treated with surgery. However, prognostic indicators that might guide HNSTS management are poorly defined. PURPOSE: Main purpose of this study is to find variables linked to HNSTS patients' prognosis. Assessment of the Tumor, Node, Metastatis (TNM) system is the secondary purpose. STUDY DESIGN, SETTING, SAMPLE: This study is a retrospective cohort performed on HNSTS patients who received surgery at the Department of Oral and Maxillofacial Head and Neck Oncology, Shanghai Ninth People's Hospital School of Medicine, Shanghai Jiao Tong University from January 1, 2006, to December 31, 2014. Strict inclusion criteria were applied. PREDICTOR VARIABLE: The predictor variable was a set of heterogenous risk factors and were grouped into the following categories: demographic (age and gender), clinical (primary tumor, tumor region, tumor size, and TNM stage), and treatment (surgical margin, treatment therapy). MAIN OUTCOME VARIABLE(S): The primary outcome variables were time to 5-year disease-free survival (DFS) and 5-year overall survival (OS). The secondary outcome variables were time to 5-year tumor local recurrence and metastasis. COVARIATES: Not applicable. ANALYSES: Descriptive statistical analysis was carried out. Pearson χ2 test was employed in univariate analysis. Cox regression was modified for multiple variable analysis with components that had significant P values in univariate analysis or variables with potential prognostic value. Log-rank test was applied to compare survival situations under various variables. P value less than .05 was statistically significant. RESULTS: The sample was composed of 100 subjects with a mean age of 43.47 (standard deviation: 16.15) years old and 56 (56%) were male. The 5-year DSF and OS were 59 and 60%, respectively. Variables associated with poor DFS and OS were age > 60 years (P = .003, hazard ratio [HR]: 4.95, 95% confidence interval [CI]: 1.71,14.1; P = .005, HR: 4.48, 95% CI: 1.57,12.8) and non-primary tumors (P＜.001, HR: 8.41, 95% CI: 2.85,24.8; P = .002, HR: 6.90, 95% CI: 2.46,19.4), respectively. Maxilla and skull base cancers had local recurrence (12/18, 66.7%) more common. T2 (TNM) tumor displayed higher tendency in DFS(P = .009, HR: 4.20, 95% CI: 1.42,12.4) and metastasis(P = .09, HR: 3.51, 95% CI: 0.82,15.0) than T1 (TNM) tumors. CONCLUSION AND RELEVANCE: Poor prognosis is associated with maxilla and skull base tumors as well as patients over 60 years. TNM stage appeared to have limited prognostic significance.

The hue of temporomandibular joint arthroscopy under local versus general anaesthesia.

BACKGROUND: Temporomandibular joint arthroscopy (TMJA) is often performed under general anaesthesia (GA) worldwide on an inpatient basis, whereas local anaesthesia (LA) is not equally considered as the standard procedure. OBJECTIVES: To compare the efficacy between LA and GA when performing TMJA. METHODS: This study retrospectively reviewed a total of 182 patients in LA group and 91 patients in GA group who underwent TMJA for the management of disc displacement. Patients were divided into two groups based on type of anaesthesia used for surgery; LA group and GA group. Comparisons were made based on operative time, intubation and extubation time (for GA only), hospital stay duration, total cost and post-operative clinical and radiological outcomes. RESULTS: The demographics and pre-operative clinical assessments were matched in both groups. No post-operative significant difference was found in outcomes when performing TMJA under LA compared to GA in terms of pain reduction (p = .016) and improvement in mouth opening (p = .866). The median operative time and hospital stay duration for LA group were significantly less compared to GA group (p < .001). GA group required an additional intubation and extubation time, whereas LA group patients were waived from it. TMJA for LA group was performed in the minor procedure setup, which reduced the costs for surgery (p < .001). Post-operative disc position was excellent and good with an overall success rate of 95%. CONCLUSION: The use of LA performing TMJA reduces operating time, costs, hospital stay and recovery room time than GA group. Furthermore, TMJA performed under LA shared similar post-operative clinical and radiological outcomes with those performed under GA.

Biomechanical Evaluation of a Standard Temporomandibular Joint Prosthesis and Screw Arrangement Optimization: A Finite Element Analysis.

BACKGROUND AND OBJECTIVE: Artificial total joint replacement is an important method of temporomandibular joint (TMJ) reconstruction, which has been advocated for TMJ osteoarthrosis, ankylosis, tumors, and other diseases. We designed one type of standard TMJ prosthesis fit for Chinese patients. This study aimed to explore the biomechanical behavior of the standard TMJ prosthesis using finite element analysis and selects an optimal screw arrangement scheme for clinical application. MATERIALS AND METHODS: A female volunteer was recruited for a maxillofacial computed tomography scan, then the Hypermesh software was used to establish a finite element model of a mandibular condyle defect repaired with an artificial TMJ prosthesis. An advanced universal finite element program software was used to calculate the stress and deformation under a simulated maximum bite force loading. Also, the forces of screws under different numbers and arrangements were analyzed. Meanwhile, we designed an experiment to verify the calculation model. RESULTS: The average maximum stress of the fossa component of the standard prosthesis model was 19.25 MPa. The average maximum stress of the condyle component was 82.58 MPa, mainly concentrated near the top row hole. The fossa component should be fixed with at least 3 screws, and the optimal number of screws was 4. The condyle component should be fixed with at least 4 screws, and its optimal number was 6. The best scheme of screw arrangement was determined. The results of the verification experiment showed that the analysis was reliable. CONCLUSIONS: The stress distribution of the standard TMJ prosthesis is uniform, meanwhile, the number and arrangement of the screws significantly affect the contact force of the screws.

Arthroscopic Disk Repositioning After Failed Open Disk Repositioning.

PURPOSE: Open disk repositioning has been long achieving excellent functional and stability outcomes. However, still remains some relapses for whom a second open surgery is often challenging. This study aimed to evaluate the effectiveness of arthroscopic disk reposition as an alternative surgery for unsuccessful cases of anterior disk displacement (ADD) after an initial open disk repositioning. MATERIALS AND METHODS: This retrospective study included all patients who underwent secondary arthroscopy for disk repositioning of the relapsed ADD after an initial open surgery between January 2012 to June 2017. The redo arthroscopic disk repositioning and suturing procedure was the primary predictor input variable in this study. Outcome evaluation was based on both clinical (visual analog scale and maximal interincisal opening) and magnetic resonance imaging data. RESULTS: Twenty-seven joints fulfilling the inclusion criteria were included. A significant improvement was detected at 24-month postoperatively compared with the baseline visual analog scale. The maximal interincisal opening showed a statistical improvement from 25.07 mm preoperatively to 38.44 mm at 24-month postoperatively. Twenty-six joints maintained a stable disk position with only 1 joint relapsed to ADD without reduction. CONCLUSION: Arthroscopic disk reposition and suturing technique is a reliable and effective repeat surgery after failed initial open disk repositioning for management of ADD.

Association between sexual maturation and anterior disc displacement of temporomandibular joint in adolescents aged 13-14 years.

OBJECTIVES: To investigate the association between sexual maturation and anterior disc displacement (ADD) of temporomandibular joint (TMJ). MATERIALS AND METHODS: Adolescents aged 13-14 years old, attending the first grade of one private junior school, were recruited. Magnetic resonance imaging (MRI) was used to confirm ADD, in addition, the serum levels of sex hormones were tested. Secondary sex characteristics, psychological evaluations, oral health-related behaviors, and sociodemographic characteristics were also collected. RESULTS: A total of 440 teenagers were included, of which the prevalence of ADD was 17.7%. Subgroup analysis revealed that age at menarche in girls and nocturnal emission, laryngeal prominence, voice change, and facial hair in boys showed significant differences between the ADD group and the normal population (all p < 0.05). The serum levels of prolactin in girls (12.23 and 9.82 ng/ml) and testosterone in boys (3.65 and 2.48 ng/dl) were significantly higher in the ADD group compared to the normal population, respectively (both p < 0.05). CONCLUSIONS: This study suggested that sexual maturation has a significant association with ADD both in boys and girls. The increased serum levels of testosterone in boys and prolactin in girls might contribute to the occurrence of TMJ ADD. CLINICAL RELEVANCE: This study provides key data to support and inform longitudinal studies as well as to explain why ADD prefers in adolescents. Main findings can also be used to prevent the occurrence of ADD and secondary jaw deformities.

Do Orthognathic Patients and Persons Without Facial Deformities Have Different Visual Attention to Menton Deviation?

PURPOSE: This study aimed to quantify how menton deviation influenced facial visual attention of orthognathic patients and persons without facial deformities, and to explore differences between them. MATERIALS AND METHODS: The visual scanning paths of 260 participants (Group I, 130 orthognathic participants; Group II, 130 participants without facial deformities) while observing images reflecting normal subjects and those with different menton deviation degrees were recorded with an eye-tracking device. The fixation duration [FD] and first fixation time [FFT]) on the areas of interest for each group were compared. RESULTS: Although Group I devoted longer FD to the lower face than the Group II when observing a normal face (P < 0.05), a menton deviation of 3°D was associated with a significantly longer FD and earlier FFT for both groups ( P < 0.05). As the severity of the menton deviation increased, this trend became more obvious, and the visual attention paid to the eyes and nose decreased (FD decreased, FFT delayed), especially for Group II ( P < 0.05). CONCLUSIONS: A menton deviation of 3° can induce abnormally increased visual attention to the lower face in both orthognathic patients and persons without facial deformities. With increased menton deviation, this trend will be more obvious, and the visual attention to the eyes and nose will also be affected, especially for persons without facial deformities, attention to the eyes will be significantly reduced.

Periosteum coverage versus collagen-membrane coverage in periodontally accelerated osteogenic orthodontics: a randomized controlled clinical trial in Class II and Class III malocclusions.

BACKGROUND: Periodontal accelerated osteogenic orthodontics (PAOO) is a widely-used clinical procedure that combines selective alveolar corticotomy, particulate bone grafting, and the application of orthodontic forces. Different modifications of PAOO such as collagen-membrane coverage can better benefit patients from preventing displacement of grafts. Due to its stability, collagen-membrane coverage gradually gained popularity and became a widely-used procedure in traditional PAOO technique. OBJECTIVES: To quantitatively investigate the radiographic changes of alveolar bone, periodontal soft tissue changes of the mandibular anterior teeth and postoperative complications in periosteum-covered techniques compared with traditional surgical technique in PAOO. METHODS: Orthodontic camouflage for dental Class II or decompensation for skeletal Class III malocclusions were included; Patients with bone defects on the buccal aspects of the anterior mandible regions confirmed by clinical and radiographic examination were randomly divided into the periosteum coverage group or traditional technique group for PAOO. Cone-beam computerized tomography (CBCT) scans were obtained before treatment (T0) and 1 week (T1) and 12 months (T2) after operation. The primary outcome variable was the vertical alveolar bone level (VBL), the secondary evaluation parameters included labial horizontal bone thickness at the midpoint of the middle third (MHBT) or apical third (AHBT) to the limit of the labial cortical surface during a 12-month follow-up. Postoperative sequelae were evaluated after 2 days and 7 days in both the groups. Periodontal parameters were analyzed at T0 and T2. RESULTS: Thirty-six adult subjects were eligible and recruited in the present study. Although experimental group exhibited more severe infection, no significant differences of the postoperative symptoms or periodontal parameters was found between the 2 groups (P > 0.05). All patients were examined respectively using CBCT at baseline (T0), postoperative 1 week (T1) and 12 months (T2). Both alveolar bone height and width increased from T0 to T1 (P < 0.001) and then reduced from T1 to T2 (P < 0.001) in both groups. However, significant bone augmentation was achieved in each group from T0 to T2 (P < 0.001). Furthermore, the vertical alveolar bone augmentation in the experimental group increased significantly than that in the traditional surgery (P < 0.05). CONCLUSIONS: Compared with traditional PAOO surgery, the periosteum-covered technique provides superior graft stabilization and satisfactory vertical bone augmentation in the labial mandibular anterior area.

Crosstalk between autophagy and microbiota in cancer progression.

Autophagy is a highly conserved catabolic process seen in eukaryotes and is essentially a lysosome-dependent protein degradation pathway. The dysregulation of autophagy is often associated with the pathogenesis of numerous types of cancers, and can not only promote the survival of cancer but also trigger the tumor cell death. During cancer development, the microbial community might predispose cells to tumorigenesis by promoting mucosal inflammation, causing systemic disorders, and may also regulate the immune response to cancer. The complex relationship between autophagy and microorganisms can protect the body by activating the immune system. In addition, autophagy and microorganisms can crosstalk with each other in multifaceted ways to influence various physiological and pathological responses involved in cancer progression. Various molecular mechanisms, correlating the microbiota disorders and autophagy activation, control the outcomes of protumor or antitumor responses, which depend on the cancer type, tumor microenvironment and disease stage. In this review, we mainly emphasize the leading role of autophagy during the interaction between pathogenic microorganisms and human cancers and investigate the various molecular mechanisms by which autophagy modulates such complicated biological processes. Moreover, we also highlight the possibility of curing cancers with multiple molecular agents targeting the microbiota/autophagy axis. Finally, we summarize the emerging clinical trials investigating the therapeutic potential of targeting either autophagy or microbiota as anticancer strategies, although the crosstalk between them has not been explored thoroughly.

Application of Virtual Planning for Three-Dimensional Guided Maxillofacial Reconstruction of Pruzansky-Kaban III Hemifacial Microsomia Using Custom Made Fixation Plate.

PURPOSE: Pruzansky-Kaban III hemifacial microsomia (HFM) is a rare congenital facial deformity, and it is challenging to reconstruct the facial appearance. The aim of the present study was to describe a technique of application of virtual planning for three-dimensional (3D) guided maxillofacial reconstruction of Pruzansky-Kaban III HFM using custom made fixation plate. METHODS: With the help of 3D models, a preoperative virtual planning and surgical simulation were performed. Computer-aided design/computer-aided manufacture (CAD/CAM) patient customized guides and custom fixation plates were designed to reconstruct the maxillofacial skull intraoperatively. Assessment was achieved through evaluation of the postoperative effects, such as imaging, facial appearance recovery and operation time. RESULTS: Five patients with Pruzansky-Kaban III HFM were enrolled into this study. The results showed an exceptional accuracy between the preoperative virtual planning and the outcomes actually achieved postoperatively. Intraoperative measurements were no longer needed and the different surgical steps became more simple and easier. The total time was distributed as: 160 minutes for the surgical time, 40 minutes for preoperative virtual plan, and 80 minutes for designing the patient specific cutting guides and custom fixation plates. The operating time and tissue damage were reduced. All cases underwent uneventful healing without any complications. CONCLUSION: The technique of patient specific guides and custom fixation plates is a reliable method of conveying the virtual plan to the operative field with higher efficiency in patients with Pruzansky-Kaban III HFM.

Accuracy of Computer-Aided Design/Computer-Aided Manufacturing Surgical Template for Guidance of Dental Implant Distraction in Mandibular Reconstruction With Free Fibula Flaps.

PURPOSE: The direction and orientation of the osteotomized upper segments in dental implant distractor (DID) can be compromised due to an unpredicted vector of distraction. The present study aimed to evaluate the accuracy of computer-aided design/computer-aided manufacturing (CAD/CAM) surgical templates to precisely guide the distraction process in lengthening of the alveolar height for functional mandibular reconstruction. PATIENTS AND METHODS: This retrospective study included all consecutive patients who underwent digitally designed mandibular reconstruction using the fibular flap and DID with the help of CAD/CAM designed surgical templates in a single-stage procedure from 2011 to 2014. First, the preoperative digital planning was performed on 3-dimensional models. Afterward, simulation of the distraction process was made on the virtual model and the resulting new height of the fibula was evaluated. The preoperative simulation was applied to accurately define the exact location and path of the DID device to achieve the suitable vertical height. The preoperative digital planning was used to help the design of the CAD/CAM surgical template, which was then fabricated by means of the 3-dimensional printing technology. The manufactured surgical template-assisted both horizontal and vertical osteotomies of the fibular segments and defining the DID path to lead the distractor into the accurate position. The outcome evaluation was achieved through comparing both preoperative virtual planning with postoperative actual outcomes. RESULTS: This study included 14 subjects, 8 were males and 6 were females. The mean age at time of surgery was 31.07 years (range 18-47). All fibular flaps showed 100% success rate. The mean vertical bone height attained with the DID device was 11.35 mm. The vertical and horizontal osteotomies of the fibular segments were completed, then the DID devices were successfully positioned guided by the template. The mean values of the linear and angular deviations for the distractor position and upper segments were calculated and recorded. The maximum linear deviation between the virtual and the postoperative actual distractors was 0.93 mm in the anteroposterior direction, and the greatest in the horizontal plane was 4.64°. CONCLUSIONS: CAD/CAM surgical templates can accurately guide the direction and orientation of the DID device for functional mandibular reconstruction; therefore, helping to improve the outcomes by accurately transferring the preoperative virtual plan to real surgical procedure.

Membrane fixation for osseous graft stabilization in periodontally accelerated osteogenic orthodontics: a comparative study.

BACKGROUND: Periodontally accelerated osteogenic orthodontics (PAOO) is a treatment for bone defects associated with a lack of bone graft stability, especially in coronal locations. This study aimed to compare a modified technique of membrane fixation that utilizes periosteal sutures (using a pouch design) with the traditional approach, which does not use membrane fixation. METHODS: Twenty-eight patients with a total of 168 teeth treated were divided into two groups: 1-A, in which patients were treated using the modified technique (with membrane fixation), and group 2-B, in which patients were treated using the traditional technique (without membrane fixation). The postoperative bone thickness was evaluated via radiographic examination. RESULTS: Postoperative improvements in bone augmentation were detected in both groups. At 12 months, the values of the CHBT (measured from the midpoint of the coronal third to the labial cortical surface, 0.84 ± 0.33 mm) and the values of VBL (measured from the alveolar crest to the cemento-enamel junction, - 2.35 ± 0.80 mm)were significantly greater in the modified technique group than those in the traditional technique group (CHBT:0.12 ± 0.21 mm and VBL:-1.39 ± 0.99 mm; P = 0.00 and P = 0.01). CONCLUSIONS: This study shows that compared to the traditional technique, the modified PAOO technique with membrane fixation using periosteal sutures provides improved graft stabilization, superior coronal augmentation and satisfactory vertical volume.

Can pattern and depth of invasion predict lymph node relapse and prognosis in tongue squamous cell carcinoma.

BACKGROUND: Tongue squamous cell carcinoma (TSCC) is a special type of oral cancer. Cervical lymph node relapse may occur in a large percentage of TSCC patients, which usually indicates poor prognosis. In this cohort study, we focused on the predictive value of the pathological features on cervical lymph node relapse and TSCC prognosis (disease free survival). METHODS: One hundred forty-one TSCC patients staged as T1-2N0 were enrolled and categorized. Subjects were followed-up for 60 months. Univariate analysis was performed with Chi-square test for cervical lymph node relapse and Kaplan-Meier survival analysis and log rank P value for patient prognosis; multivariate analysis was also utilized with Cox regression. RESULTS: In univariate analysis, trabes growth pattern, depth of invasion greater than 4 mm, poor pathological differentiation and neurovascular invasion were considered as risk factors for cervical lymph node relapse and poor prognosis. In multivariate analysis, only patients with trabes growth pattern in the invasive front or depth of invasion larger than 4 mm had a higher risk of metastasis. Elder age group and trabes growth pattern of invasive front were considered as predictors of poor prognosis. Bad habits of smoking and alcohol consumption were related to the higher risk of metastasis. CONCLUSION: Trabes growth pattern of invasive front was a potent risk factor for TSCC cervical lymph node relapse and indicated poor prognosis. Preventive therapy including selective neck dissection was thus suggested for certain patients. TRIAL REGISTRATION: Not applicable.

A Novel Surgical Technique for Augmented Corticotomy-Assisted Orthodontics: Bone Grafting With Periosteum.

PURPOSE: To introduce grafting fixed with the periosteum (dumpling technique) as an alternative surgical technique for augmented corticotomy-assisted orthodontics in the lower anterior region and evaluate the preliminary outcomes. MATERIALS AND METHODS: Eleven patients (9 women, 2 men; mean age, 21.4 yr) with a thin alveolus or alveolar defect in the lower anterior region by clinical and radiographic examination underwent an augmented corticotomy using the new dumpling technique. Cone-beam computerized tomography was used to evaluate morphologic changes of the lower anterior ridge before treatment (T0) and 1 week (T1) and 6 months (T2) after the bone-augmentation procedure. Repeated-measures analysis of variance with Bonferroni multiple-comparison test was used to compare variables at each time point. RESULTS: No severe postsurgical complications occurred in any patient. The mean alveolar bone thickness of the labial plate increased from T0 to T1 (P < .001) and decreased from T1 to T2 (P < .001). However, compared with T0, there was still a significant increase in horizontal bone thickness at T2 (P < .05). The vertical alveolar bone level increased from T0 to T1 (P < .001) and was maintained from T1 to T2 (P > .05). No significant differences were found in root length of the lower anterior teeth at these 3 time points (P > .05). CONCLUSIONS: In this preliminary study, the dumpling technique for augmented corticotomy-assisted surgical orthodontics showed alveolar bone augmentation by increasing the vertical alveolar height and the horizontal bone thickness in the labial aspect of the anterior mandibular area. However, long-term follow-up is necessary.

Retrieval of root fragment in maxillary sinus via anterolateral wall of the sinus to preserve alveolar bone.

PURPOSE: The objective of this study was to present a functional surgery for retrieval of displaced root fragments from the maxillary sinus while preserving the alveolar bone. MATERIALS AND METHODS: Twenty-one patients with associated root fragments displaced into the maxillary sinus after tooth extraction were collected and reviewed retrospectively. All patients included in the study were subjected to surgical removal of the displaced root by the use of piezosurgery. In case the root fragment was barely detectable, endoscopy would be helpful. RESULTS: Eleven roots were removed via small windows and 10 roots via large windows. Endoscopy was used in 2 patients. Granulomatous tissues were found around 6 root fragments, and cyst formation was found in 1 patient. Only 1 patient had sinusitis temporarily. No patients developed complications such as facial paresthesia, facial asymmetry, or infection. CONCLUSIONS: The functional surgery for the retrieval of a displaced root from the maxillary sinus is recommended owing to quick recovery, preservation of alveolar bone, and minimal complications.

Effect of arthroscopic discopexy on condylar growth in adolescents with temporomandibular joint disc displacement without reduction: A retrospective self-controlled case series study.

This study was a retrospective self-controlled study that aimed to evaluate the effect of arthroscopic discopexy on condylar height and mandibular position in adolescents with temporomandibular joint (TMJ) anterior disc displacement without reduction (ADDwoR). Patients between 10 and 20 years of age and diagnosed with bilateral TMJ ADDwoR by magnetic resonance image (MRI) were included in this study. All patients underwent a period of natural course before arthroscopic surgery and then a follow-up period postoperatively. Changes in condylar height and mandibular position were measured by MRI and X-ray radiographs. Data were analyzed by paired t-test, Pearson correlation analysis, and generalized estimating equations. This study comprised a total of 40 patients with a mean age of 14.80 years. Pearson correlation analysis showed correlations between condylar height and mandibular position changes. The condylar height change during the post-operative period was significantly higher than that during natural course period (3.57 mm, p < 0.001). The changes in mandibular position (including ANB angle, SNB angle, and Pog-Np) were significant different (all p < 0.05) between the two periods. This study found that arthroscopic discopexy can promote condylar growth and correct dentofacial deformity in adolescents with bilateral TMJ ADDwoR.

Distinctive mesenchymal-like neurofibroma stem cells shape NF1 clinical phenotypes controlled by BDNF microenvironment.

BACKGROUND: Neurofibroma type I (NF1) often presents with multiple clinical phenotypes due to mutations of NF1 gene. The aim of this study was to determine the phenotypic and therapeutic relevance of tumor microenvironment in NF1 patients. METHODS: Tumor stem cells (TSCs) from NF1 were isolated and cultured using fluorescence activated cell sorting (FACS) and colony formation experiments. Then, flow cytometry was used to detect the surface markers, osteogenic and adipogenic differentiation were performed as well. Its tumorigenesis ability was confirmed by subcutaneous tumorigenesis in nude mice. Immunohistochemical staining was performed on neurofibroma tissues from the head and trunk with different phenotypes. The expression of BDNF in neurofibroma tissues was detected by Elisa and immunohistochemical staining. Western Blotting was used to detect the expression of p38 MAPK pathway in TSCs. The effect of BDNF neutralizing antibody on the tumorigenesis of TSCs was observed. RESULTS: Herein, we advocate that NF1 contain a new subgroup of mesenchymal-like neurofibroma stem cells (MNSCs). Such colony-forming MNSCs preserved self-renewal, multiple differentiation and tumorigenic capabilities. More interestingly, the MNSCs isolated from neurofibroma tissues of the same patient with different phenotypes presented site-specific capabilities. Moreover, different levels of brain-derived neurotrophic factor (BDNF) in neurofibroma tissues can impact the MNSCs by activating the TrkB/p38 MAPK pathway. Systemic administration of BDNF neutralizing antibodies inhibited MNSCs' characteristics. CONCLUSIONS: We demonstrated that BDNF can modulate MNSCs and thereby controlling different tumor phenotypes between the head and trunk regions. Application of BDNF neutralizing antibodies may inhibit p38 MAPK pathway, therefore providing a promising strategy for managing NF1.

Characteristics of patients with temporomandibular joint idiopathic condylar resorption.

OBJECTIVE: To investigate characteristics of temporomandibular joint (TMJ) idiopathic condylar resorption (ICR) and analyze the related factors. METHODS: A total of 755 consecutive patients (150 with ICR and 605 with anterior disc displacement [ADD]) from July 2015 to December 2018 were recruited. A comprehensive questionnaire characterizing the multidimensional impact of the TMJ was designed. Clinical examination and radiological evaluation were also performed. The odds ratio for each variable in the ICR group versus the ADD group was computed using logistic regression analysis. RESULTS: Multivariate logistic regression analysis showed significant correlations between mouth opening restriction, disease course, mandibular retrusion, mandibular retrusion progression, skeletal Class II profile, and overjet in ICR patients. CONCLUSION: These results suggest that a longer ADD disease course might have a strong relationship with ICR.

Multiparametric CT-based assessment of pretracheal anatomical relationships for safe tracheotomy: A long-forgotten issue revisited.

OBJECTIVES: To assess the anatomical relationships and variations in the pretracheal space and to guide tracheotomy procedures in a safe manner with image-based evidence. MATERIALS AND METHODS: A retrospective study was conducted on unirradiated patients requiring elective tracheotomies. Preoperative contrast-enhanced CT (CECT)/CT venography (CTV) was applied for an anatomical evaluation of the pretracheal region. Vascular morphologies were compared for three vessels: the anterior jugular vein (AJV), the innominate artery (IA) and the inferior thyroid vascular plexus (ITVP). The relationships between the thyroid isthmus and the 2nd-4th tracheal rings were also analyzed. RESULTS: A total of 120 patients were identified, most of whom (n = 110, 91.7%) had head and neck squamous cell carcinomas. Patients with recognizable AJVs (n = 118) were divided into 3 groups: single-branch (n = 11, 9.2%), double-branch (n = 105, 87.5%), and multibranch (n = 2, 1.7%). In addition, IAs were categorized as low-bifurcation (n = 51, 42.5%), high-bifurcation (n = 40, 33.3%), platform (n = 27, 22.5%) and variant types (n = 2, 1.7%). Within the platform types, high-lying IAs (n = 15, 8.3%) might have interfered with the standard tracheal incisions due to possible IA-tracheal overlay. This interference was also related to the height of intraoperative tracheal incisions (rn = 0.364, P = 0.001). Within ITVPs, independent-trunk types were found in 71 cases (59.2%), while common-trunk types were found in 45 (37.5%). In addition, a low thyroid isthmus (suprasternal-isthmus distance <3 cm) was found in 83 cases (69.2%). CONCLUSIONS: CT image-based evidence can prepare junior practitioners with important pretracheal anatomical information, thereby facilitating safer tracheotomy procedures. Our results shed light on vascular relationships for emergent tracheotomy.

Anteromedial thigh septocutaneous perforator flap as a first choice for head and neck reconstruction: A clinical algorithm based on perforator-pedicle relationship.

BACKGROUND: Anterolateral thigh perforator flaps (ALTPFs) have long been considered workhorse flaps for head and neck reconstructions. However, in some instances, anteromedial thigh septocutaneous perforator flaps (AMTPFs) are easier to harvest than ALTPFs. This study aimed to determine when and how the AMTPF should be considered the first choice as a reconstructive tool. METHODS: A retrospective cohort study was performed in the Department of Oral and Maxillofacial Surgery-Head & Neck Oncology, Shanghai Ninth People Hospital, from January 2014 to December 2018. Both the perforator-pedicle relationships and postoperative functional outcomes were compared. RESULTS: A total of 168 patients were included in this study, among whom 49 underwent AMTPF reconstructions. The AMTPF perforators in this study were mostly septocutaneous (n = 38, 77.5%). Notably, the AMTPF perforators mainly originated from the medial branch of the descending branches of the lateral circumflex femoral arteries (n = 44, 89.8%), while for the other 5 patients, the perforators were found to originate from the superficial femoral arteries. Additionally, the average pedicle length of the AMTPFs was 8.7 cm (range: 6.0 to 13.0 cm), which was comparable to that of the ALTPFs (8.9 cm) (p = 0.442). The postoperative complication rate and functional outcomes were comparable between the two groups. The algorithm and harvesting approaches are presented. CONCLUSIONS: The role of AMTPF should not be downplayed. After careful preoperative evaluation, we believe that AMTPF should not be considered a second choice in patients with sizable septocutaneous perforators.

Facial visual attention to menton deviation: An objective evaluation by laypeople.

PURPOSE: This study aimed to quantitatively evaluate whether the severity of menton deviation (MD) influenced facial perceptions of laypeople. We also aimed to determine the effectiveness of surgery in normalizing the distribution of the facial visual attention of laypeople. METHODS: The scanning paths of 177 laypeople were recorded using an eye tracking device while observing images of individuals without MD and pre- and post-treatment subjects with different degrees of MD. The fixation durations on the areas of interest (AOIs) in each group were compared and analysed. RESULTS: When observing the images of non-MD subjects, the eyes were the focus of the most significant fixation (higher than the fixations on the nose and lower face). When the MD increased to 3°, attention on the lower face increased (p = 0.001) with decreased attention to the eyes (p = 0.0126). At an MD of 9°, attention to the lower face sharply increased, even more so than that to the eyes, with decreased attention to the nose (p = 0.0104). Compared with the findings for the post-treatment images, the laypeople who observed the pretreatment images focused longer on the lower face and less on the eyes and nose (p = 0.001, p = 0.0322 and p = 0.0023, respectively). The distribution of the fixation duration when observing the post-treatment images was similar to that when observing the images of the non-MD subjects. CONCLUSIONS: Laypeople can perceive an MD of 3°, which causes changes in the distribution of visual attention, with attention focusing on the MD. When the deviation reaches 9°, it is very noticeable. Surgery can normalize the distribution of the facial visual attention of laypeople, as shown by the responses to the post-treatment images.