A Temporary Intraoperative Fixation Method for the Absorbable Plates Fixation of Condylar Fracture by Retromandibular Transparotid Approach.

The authors describe a temporary intraoperative fixation method for the absorbable plates' fixation of subcondylar fracture by retromandibular transparotid approach. First, the fracture was temporarily fixed with a 4-hole titanium microplate across the fracture line in the center of the lateral surface of the condyle to maintain the reduction of the fracture. Then, two 4-hole absorbable mini-plates were fixed on the posterior and anterior border of the condylar neck. Finally, the 4-hole titanium microplate and screws were removed before the wound closure. In the absorbable plates' fixation of subcondylar fracture by transparotid approach, the method of temporary intraoperative fixation using a 4-hole titanium microplate offsets the limited exposure of the operative field, smooths the operation, and offers the reliability and validity of the absorbable plates' fixation.

Feasibility of 2-Point Fixation by Absorbable Plates Using the Transoral Approach in Management of the Zygomatic Complex Fractures.

PURPOSE: The purpose of this study was to retrospectively evaluate the feasibility of 2-point fixation using absorbable plates by the transoral approach in the management of the zygomatic complex (ZMC) fractures. METHODS: Twenty-five patients (15 male and 10 female, age range 16 y to 55 y) with Knight and North Group Ⅲ zygomatic fractures were included in this case series. Open reduction by intraoral approach was performed on these patients, and the fractures were fixed using absorbable plates placed at the zygomaticomaxillary buttress and infraorbital rim. Postoperatively, follow-up was undertaken to evaluate the fracture healing, mouth opening, facial asymmetry, diplopia, and paresthesia. RESULTS: Postoperatively, all patients achieved uneventful healing; facial symmetry and wound healing were achieved, along with sensory recovery involving the infraorbital nerve. Complications such as sensory disturbances, infection, diplopia, malunion, and nonunion were not encountered in these patients. CONCLUSIONS: Two-point fixation using absorbable plates by transoral approach can provide sufficient stabilization for Knight and North Group III zygomatic fractures.

Pollen-Modified Flat Silk Cocoon Pressure Sensors for Wearable Applications.

Microstructures have been proved as crucial factors for the sensing performance of flexible pressure sensors. In this study, polypyrrole (PPy)/sunflower pollen (SFP) (P/SFP) was prepared via the in situ growth of PPy on the surface of degreased SFP with a sea urchin-like microstructure; then, these P/SFP microspheres were sprayed onto a flat silk cocoon (FSC) to prepare a sensing layer P/SFP-FSC. PPy-FSC (P-FSC) was prepared as an electrode layer through the in situ polymerization of PPy on the FSC surface. The sensing layer P/SFP-FSC was placed between two P-FSC electrode layers to assemble a P/SFP-FSC pressure sensor together with a fork finger electrode. With 6 mg/cm2 of optimized sprayed P/SFP microspheres, the prepared flexible pressure sensor has a sensitivity of up to 0.128 KPa-1 in the range of 0-13.18 KPa and up to 0.13 KPa-1 in the range of 13.18-30.65 KPa, a fast response/recovery time (90 ms/80 ms), and a minimum detection limit as low as 40 Pa. This fabricated flexible P/SFP-FSC sensor can monitor human motion and can also be used for the encrypted transmission of important information via Morse code. In conclusion, the developed flexible P/SFP-FSC pressure sensor based on microstructure modification in this study shows good application prospects in the field of human-computer interaction and wearable electronic devices.

Application of deep learning in isolated tooth identification.

BACKGROUND: Teeth identification has a pivotal role in the dental curriculum and provides one of the important foundations of clinical practice. Accurately identifying teeth is a vital aspect of dental education and clinical practice, but can be challenging due to the anatomical similarities between categories. In this study, we aim to explore the possibility of using a deep learning model to classify isolated tooth by a set of photographs. METHODS: A collection of 5,100 photographs from 850 isolated human tooth specimens were assembled to serve as the dataset for this study. Each tooth was carefully labeled during the data collection phase through direct observation. We developed a deep learning model that incorporates the state-of-the-art feature extractor and attention mechanism to classify each tooth based on a set of 6 photographs captured from multiple angles. To increase the validity of model evaluation, a voting-based strategy was applied to refine the test set to generate a more reliable label, and the model was evaluated under different types of classification granularities. RESULTS: This deep learning model achieved top-3 accuracies of over 90% in all classification types, with an average AUC of 0.95. The Cohen's Kappa demonstrated good agreement between model prediction and the test set. CONCLUSIONS: This deep learning model can achieve performance comparable to that of human experts and has the potential to become a valuable tool for dental education and various applications in accurately identifying isolated tooth.

A Latest Review on Micro- and Nanoplastics in the Aquatic Environment: The Comparative Impact of Size on Environmental Behavior and Toxic Effect.

Micro and nanoplastics (MNPs) have attracted growing global research attention due to their distinct environmental impacts, addressing escalating concerns. The diverse materials, sizes, and shapes of MNPs result in a range of environmental impacts. Size, a crucial characteristic of MNPs, influences their environmental behavior, affecting processes like migration, sedimentation, aggregation, and adsorption. Moreover, size modulates the biodistribution and toxicity of MNPs in aquatic organisms. This review delves into the comprehensive impacts of plastic size, with a primary focus on environmental behavior and toxic effects. Ultimately, this review emphasizes the ecological implications of MNP size, laying a foundation for future research in this field.

A critical review on graphene oxide membrane for industrial wastewater treatment.

An important way to promote the environmental industry's goal of carbon reduction is to promote the recycling of resources. Membrane separation technology has unique advantages in resource recovery and advanced treatment of industrial wastewater. However, the great promise of traditional organic membrane is hampered by challenges associated with organic solvent tolerance, lack of oxidation resistance, and serious membrane fouling control. Moreover, the high concentrations of organic matter and inorganic salts in the membrane filtration concentrate also hinder the wider application of the membrane separation technology. The emerging cost-effective graphene oxide (GO)-based membrane with excellent resistance to organic solvents and oxidants, more hydrophilicity, lower membrane fouling, better separation performance has been expected to contribute more in industrial wastewater treatment. Herein, we provide comprehensive insights into the preparation and characteristic of GO membranes, as well as current research status and problems related to its future application in industrial wastewater treatment. Finally, concluding remarks and future perspectives have been deduced and recommended for the GO membrane separation technology application for industrial wastewater treatment, which leads to realizing sustainable wastewater recycling and a nearly "zero discharge" water treatment process.

Serious Condylar Head Absorption in Children With Intracapsular Condylar Fractures Treated Operatively With Long Screws.

OBJECTIVE: This study was performed to explore bone remodelling in children with intracapsular condylar fractures after the condylar fracture fragments were fixed using long screws and to offer possible explanations about the underlying mechanism. PATIENT AND METHODS: Records of children (less than 12 y old) who sustained intracapsular condylar fractures and fixed with long screws from May 2012 to January 2015 were retrieved. Age, gender, dates of injury, admission, and discharge, mechanism of trauma, location and pattern of fracture, other mandibular fractures, treatment methods, and time of review were recorded and analyzed. Image dates of pretreatments and posttreatments, including the date of review, were also recorded. RESULTS: A total of 8 patients completed their follow-up, and all patients (n=5) who were followed up after more than 3 months showed serious resorption of the condylar head. The condylar head resorbed until the height (or articular surface) dropped and aligned with the surface of the screw. The shortest time of absorption, as shown by the computed tomography scan was 106 days, and the longest time was 171 days (average time of 141.8 d). CONCLUSIONS: Intracapsular condyle fractures in children should be managed conservatively as much as possible. However, if the height of the fracture fragments drops remarkably, open reduction and rigid internal fixation become possible choices.

Combination of PD-1 inhibitor with GVD (gemcitabine, vinorelbine, liposomal doxorubicin) versus GVD regimen as second-line therapy for relapsed/refractory classical Hodgkin lymphoma.

Patients with classical Hodgkin lymphoma (cHL) who do not achieve complete remission (CR) after second-line chemotherapy have poor clinical outcomes. Besides, conventional salvage chemotherapy regimens have an unsatisfactory CR rate. The present retrospective study reports the efficacy and toxicity of the GVD (gemcitabine, vinorelbine, liposomal doxorubicin) regimen with or without programmed cell death 1 (PD-1) inhibitor for patients with cHL who failed first-line treatment. A total of 103 patients with cHL (GVD+PD-1 group, n = 27; GVD group, n = 76) with response assessment based on positron emission tomography were included. The GVD+PD-1 group tended to have a higher CR rate than GVD group (85·2% vs. 65·8%, P = 0·057) and had a better event-free survival (EFS) (P = 0·034). Subgroup analysis showed that patients with low-risk second-line International Prognostic Score might benefit from the addition of PD-1 inhibitor (GVD+PD-1 vs. GVD, 100·0% vs. 64·7%, P = 0·028) and had better EFS than GVD alone (P = 0·016). Further analysis demonstrated that PD-1 consolidation therapy might provide an EFS benefit (P = 0·007). The toxicity of the GVD+PD-1 regimen was comparable to the GVD regimen, except for higher rates of hypothyroidism and autoimmune pneumonitis, which were manageable. In conclusion, combining a PD-1 inhibitor with a GVD regimen could be a potentially effective second-line therapy for patients with cHL.

Surface Adsorption-Mediated Ultrahigh Efficient Peptide Encapsulation with a Precise Ratiometric Control for Type 1 and 2 Diabetic Therapy.

A surface adsorption strategy is developed to enable the engineering of microcomposites featured with ultrahigh loading capacity and precise ratiometric control of co-encapsulated peptides. In this strategy, peptide molecules (insulin, exenatide, and bivalirudin) are formulated into nanoparticles and their surface is decorated with carrier polymers. This polymer layer blocks the phase transfer of peptide nanoparticles from oil to water and, consequently, realizes ultrahigh peptide loading degree (up to 78.9%). After surface decoration, all three nanoparticles are expected to exhibit the properties of adsorbed polymer materials, which enables the co-encapsulation of insulin, exenatide, and bivalirudin with a precise ratiometric control. After solidification of this adsorbed polymer layer, the release of peptides is synchronously prolonged. With the help of encapsulation, insulin achieves 8 days of glycemic control in type 1 diabetic rats with one single injection. The co-delivery of insulin and exenatide (1:1) efficiently controls the glycemic level in type 2 diabetic rats for 8 days. Weekly administration of insulin and exenatide co-encapsulated microcomposite effectively reduces the weight gain and glycosylated hemoglobin level in type 2 diabetic rats. The surface adsorption strategy sets a new paradigm to improve the pharmacokinetic and pharmacological performance of peptides, especially for the combination of peptides.

Dopamine Functionalized Polyethylene Glycol for Improving Stability of Gold Nanoparticles against Reactive Oxygen Species in Serum.

PEGylation is the most effective antifouling method for the surface modification of gold nanoparticles (AuNPs). However, thiol-terminated polyethylene glycol (PEG) ligands tethered on the AuNPs are instable in serum and can detach from the AuNP surface, resulting in a significant reduce of their antifouling properties. Herein, it is reported that reactive oxygen species (ROS) is a major factor causing the detachment of PEG ligands from AuNP surfaces. By covalently backfilling dopamine-functionalized PEG on the AuNPs, the stability of PEG ligands on AuNP surface and the antifouling ability of AuNPs can be effectively improved. Tuning the balance between ROS and dopamine-functionalized PEG can be used as a new strategy to control the self-assembly of AuNPs and serum proteins.

Microplastics contamination in groundwater of a drinking-water source area, northern China.

Although the contamination of microplastics (MPs) in groundwater has been anticipated, their occurrence, distribution, and composition require further understanding. In this study, the occurrence and distributions of MPs were investigated in shallow groundwater from an important water source district in Tianjin city of northern China. The abundance, the physical morphology, the chemical composition, and the potential correlations of the determined MPs with human activities were thoroughly characterized. MPs were determined from all ten sampling sites with the abundance ranged between 17.0 ± 2.16 to 44.0 ± 1.63 n/L, revealing the ubiquitous existed MPs contamination. Based on the physical categorization, fiber (44.74%) was the most abundant shape, while blue (31.02%) and transparent (26.09%) were the most prevalent colors. The dominant size of MPs was smaller than 200 µm which accounted for 73.10%. A total of seven types of MPs were determined with polyethylene, polyethylene terephthalate, and polystyrene as the main types, of which, polypropylene showed strong positive correlations with polystyrene, indicating the possible similar sources of them. Besides, the determined MPs in groundwater were greater in areas with the high population density and strong population activity, indicating their high correlation with human activity. The study highlighted the presence of MPs in groundwater of drinking water source in northern China and provided useful information for evaluating the potential ecological effects on water quality safety and human health brought by MPs.

Development of gestational diabetes mellitus in women with periodontitis in early pregnancy: A population-based clinical study.

AIM: This study aimed to determine whether periodontitis in early pregnancy and periodontal therapy during gestation affect the incidence of gestational diabetes mellitus (GDM) through a population-based clinical study. MATERIALS AND METHODS: Subjects without periodontitis at 1-4 weeks of gestation who met our inclusion criteria were enrolled in the non-periodontitis group. Periodontitis patients who agreed or refused to receive periodontal therapy during pregnancy were separately enrolled in the periodontitis treated or untreated group. At 12-16 weeks of gestation, gingival crevicular fluid (GCF) and venous blood were collected for analyses of bacterial species and serum inflammatory mediators, respectively. At 24-28 weeks of gestation, GDM patients were identified by oral glucose tolerance tests. The association tests were performed using Chi-squared statistics and regression analyses. RESULTS: The complete data of 3523 pregnant women were recorded during the study period. GDM incidence among the untreated periodontitis participants (84/749, 11.21%) was significantly higher than that among the non-periodontitis participants (108/2255, 4.79%) (p < .05), and periodontal treatment during gestation reduced the incidence from 11.21% (untreated group) to 7.32% (38/519, treated group) (p < .05). Based on multiple logistic regression analyses, it was found that periodontitis in early pregnancy was associated with GDM, and three-step regression analyses showed that Porphyromonas gingivalis (P. gingivalis) and the serum TNF-α and IL-8 levels played a role in the association between untreated periodontitis and GDM. Furthermore, Pearson's correlation test indicated that the existence of P. gingivalis in GCF was positively correlated with high serum levels of these two inflammatory mediators. CONCLUSIONS: This study establishes a connection between periodontitis in early pregnancy and GDM and demonstrates that the presence of P. gingivalis is associated with high levels of inflammatory mediators in serum, and thereby may contribute to the development of GDM. In-depth mechanistic studies are needed to further support these findings.

Treatment of Sagittal Fracture of the Mandibular Condyle Using Resorbable-Screw Osteosynthesis.

PURPOSE: Screw osteosynthesis is advocated for the treatment of sagittal fracture of mandibular condyle (SFMC). This study aimed to explore the applicability of resorbable-screw osteosynthesis in the treatment of SFMC. METHODS: A retrospective cohort study was performed in patients with SFMC treated with resorbable-screw osteosynthesis (group A) from June 2011 through June 2021. The patients who had undergone titanium-screw osteosynthesis served as the control group (group B). The primary outcome variable was fracture healing, defined as follows: 1) normal mouth opening and restoration of pretrauma occlusion; 2) without complications or discomfort of temporomandibular joint symptoms; and 3) fracture union without abnormal reactions or bone resorption in computed tomography images. The secondary outcome variable was condylar morphological changes including radiographic imaging appearance of the condyle, mandibular ramus height (MRH), anteroposterior diameter (APD), and mediolateral diameter (MLD) of the condyle, which were assessed by comparing the computed tomography images 1 week after surgery with those of 3 months after surgery. The collected data of the outcome variables of the 2 groups were analyzed correspondingly using Student's paired t test and Student's t test. RESULTS: There were 24 patients in group A and 71 patients in group B. All the patients displayed an evident improvement in mouth opening and restored pretrauma occlusion. Few patients had complications (group A, 8.33%; group B, 9.86%) and discomfort of temporomandibular joint symptoms (group A, 16.67%; group B, 15.49%). Fracture union without abnormal reactions or bone resorption was observed during the follow-up. The radiographic evaluation revealed no significant difference in the MRH, the maximum APD, and MLD of the condyles between 1 week and 3 months after surgery in both groups. There were no significant intergroup differences in the changes in the MRH, APD, and MLD of the condyles. CONCLUSIONS: Resorbable-screw osteosynthesis is a viable option for the treatment of SFMC.

Application of a multimedia-supported manikin system for preclinical dental training.

AIM: In this study, we aimed to describe a multimedia-supported manikin system, compare the new manikin with the traditional manikin and evaluate its effectiveness in preclinical dentistry training. METHODS: A total of 150 students participated in this study. Amongst these students, 71 in the 2015-year group used traditional manikins (Group TM) for preclinical training courses (endodontics training courses and prosthodontics training courses), and 79 in the 2016-year group used manikins with a multimedia system (Group MM). The scores of the training courses between the two groups were compared. A questionnaire survey was used to collect opinions of the students in Group MM on their experience of using the multimedia-supported manikin system in the preclinical training. RESULTS: In the endodontics training courses, the scores of Group MM were higher than those of Group TM, but there was no significant difference (P = 0.379 > .05). However, the scores of prosthodontics training courses in Group MM were significantly higher than those in Group TM (P = 0.018 < .05). The questionnaire results indicated that the students in Group MM were satisfied with the device in usability, clarity, effectiveness and improvement in operation proficiency. CONCLUSIONS: In the groups studied, for preclinical dental training, the multimedia-supported manikin system was a good alternative to traditional manikin in preclinical dentistry training.

Removal of Fracture Fragments in Intracapsular Condylar Fractures: An Alternative Treatment Option.

OBJECTIVE: This study aimed to explore bone remodeling after condylar fracture fragments have been removed from patients with intracapsular condylar fractures. it also evaluated whether condyle fracture removal can be used alternatively when the authors treat patients with comminuted or small pieces of fracture or in extremely difficult operations. METHODS: Records of patients who sustained intracapsular condylar fractures and treated by removal of fragments for the period of February 2013 to September 2019 were retrieved. Data about age, gender, date of injury, dates of admission and discharge, mechanism of trauma, location and pattern of fracture, other mandibular fracture, treatment methods and time of review were recorded and analyzed. Image dates of pre- and post-treatment (including the time of review) were also recorded. RESULTS: The data of a total of 103 patients ranging from 5 to 84 years old were retrieved during this study. A total of 135 sides of condylar fragments were removed. Almost all of the patients with comminuted condyle head fracture or type A fracture presented apparent shortening of the ramus height, and none of them showed osteogenesis (or new bone formation) during their follow-up. Present study only observed osteogenesis in few patients who sustained type B/C intracapsular condylar fractures during their follow-up. The younger the patient was, the longer the follow-up time was, and the higher the possibility of new bone formation was. No correlation was found between the amount of osteogenesis and follow-up time, the amount of osteogenesis was generally small, and no patient could form a new condyle head similar to the normal (or original) condyle head. Condylar hypertrophy only occurred in children. Four patients developed temporomandibular joint ankylosis. CONCLUSIONS: Removal of fracture fragments is an alternative treatment option for patients who sustained comminuted or small pieces of fracture or in extremely difficult operations.

A Multi-Scale Study on Deformation and Failure Process of Metallic Structures in Extreme Environment.

It is a macro-micro model study for defect initiation, growth and crack propagation of metallic truss structure under high engine temperature and pressure conditions during the reentry atmosphere. Till now, the multi-scale simulation methods for these processes are still unclear. We explore the deformation and failure processes from macroscale to nanoscale using the Gas-Kinetic Unified Algorithm (GKUA) and all-atomic, molecular dynamic (MD) simulation method. The behaviors of the dislocations, defect evolution and crack propagation until failure for Aluminum-Magnesium (Al-Mg) alloy are considered with the different temperature background and strain fields. The results of distributions of temperature and strain field in the aerodynamic environment obtained by molecular dynamics simulations are in good agreement with those obtained from the macroscopic Boltzmann method. Compared to the tensile loading, the alloy structure is more sensitive to compression loading. The polycrystalline Al-Mg alloy has higher yield strength with a larger grain size. It is due to the translation of plastic deformation mode from grain boundary (GB) sliding to dislocation slip and the accumulation of dislocation line. Our findings have paved a new way to analyze and predict the metallic structural failure by micro-scale analysis under the aerodynamic thermal extreme environment of the reentry spacecraft on service expiration.

Colloidal Jamming by Interfacial Self-Assembled Polymers: A Robust Route for Ultrahigh Efficient Encapsulation.

The control of cargo phase-transfer is of interest for many applications in science and technology. Herein, we report a simple, versatile and robust method to block the phase-transfer of cargo colloids by interfacial self-assembled amphiphilic polymer molecules. After simply increasing the concentration of amphiphilic polymers, the orientation of interfacial polymer molecules changed from flat to upright, forming a thick three-dimensional polymer layer at the oil-water interface. Even under fierce external force, this thick interfacial layer robustly prevented the phase-transfer of cargo colloids, resulting in an ultrahigh encapsulation efficiency (up to 97.1 %) for proteins and peptides. One single injection of high insulin-loaded microcomposites (58.3 wt%) kept the blood glucose level within the normoglycemic state for 10 days in type 1 diabetic rats. The mass of administrated amphiphilic polymers was 1889 times smaller than that of microcomposites prepared with non-amphiphilic ones.

Hydrogeochemistry and health hazards of fluoride-enriched groundwater in the Tarim Basin, China.

Fluoride (F-) enrichment reduces the availability of groundwater resources in the arid region, and it is thus important to investigate the hydrogeochemistry and health hazards of fluoride-enriched groundwater. Seventy-two groundwater samples (20 unconfined samples from the piedmont plain, 22 unconfined samples and 30 shallow confined samples from the alluvial plain) were collected in the Tarim Basin of China to illustrate the geochemical processes driving the F- enrichment and the incidence of dental fluorosis. The patterns of average ions contents in groundwater are Na+ > Ca2+ > Mg2+ > K+ and SO42- > Cl- > HCO3- > NO3- > F-. The highest F- concentration (average 2.16 mg/L) is observed in unconfined groundwater in the alluvial plain, while the lowest (average 0.63 mg/L) is recorded in unconfined groundwater in the piedmont plain. Approximately 5.0% of unconfined groundwater in the piedmont plain, 90.9% of unconfined groundwater and 33.3% of shallow confined groundwater in the alluvial plain contain F- concentrations exceeding 1.0 mg/L (Chinese drinking water standard). Mineral dissolution, cation exchange, and evaporation play a significant role in the formation of solutes in groundwater. High-F- groundwater is mostly associated with SO4·Cl-Na·Ca, SO4·Cl-Na·Mg, and SO4·Cl-Na types water. Thermodynamic simulations reveal that the dissolution of F-bearing minerals (e.g., fluorite) significantly controls the F- contents in groundwater. High concentrations of F- are closely related to high HCO3-, high Na+, high salinity, cation exchange, and evaporation. This demonstrates that high F- concentrations are caused by the increase in fluorite solubility due to high ionic strength, Ca2+ consumption and the desorption of F- from solid surfaces under alkaline conditions. Mixing with the upper unconfined groundwater plays a vital role in the enrichment of F- in shallow confined groundwater in the alluvial plain. The health risk assessment based on Dean's classification indicates that the percentage prevalence of fluorosis for boys aged 6 to 18 is 15.5% for Yecheng (YC), 18.4% for Zepu (ZP), 33.3% for Shache (SC), 29.8% for Maigaiti (MG), and 44.9% for Bachu (BC), while that for girls of the same age is 14.3% for YC, 24.3% for ZP, 42.2% for SC, 41.4% for MG, and 45.3% for BC. For male and female adults aged between 19 and 68, the percentage prevalence of fluorosis is: YC (11.5%, 12.0%), ZP (18.3%, 20.0%), SC (35.4%, 35.0%), MG (32.5%, 39.7%), and BC (42.4%, 44.3%). It is obvious that younger generation, especially girls, suffers from more severe dental fluorosis. This study has implications for the effective management of high-F- groundwater in arid regions.

Injectable stress relaxation gelatin-based hydrogels with positive surface charge for adsorption of aggrecan and facile cartilage tissue regeneration.

BACKGROUND: Cartilage injury and pathological degeneration are reported in millions of patients globally. Cartilages such as articular hyaline cartilage are characterized by poor self-regeneration ability due to lack of vascular tissue. Current treatment methods adopt foreign cartilage analogue implants or microfracture surgery to accelerate tissue repair and regeneration. These methods are invasive and are associated with the formation of fibrocartilage, which warrants further exploration of new cartilage repair materials. The present study aims to develop an injectable modified gelatin hydrogel. METHOD: The hydrogel effectively adsorbed proteoglycans secreted by chondrocytes adjacent to the cartilage tissue in situ, and rapidly formed suitable chondrocyte survival microenvironment modified by ε-poly-L-lysine (EPL). Besides, dynamic covalent bonds were introduced between glucose and phenylboronic acids (PBA). These bonds formed reversible covalent interactions between the cis-diol groups on polyols and the ionic boronate state of PBA. PBA-modified hydrogel induced significant stress relaxation, which improved chondrocyte viability and cartilage differentiation of stem cells. Further, we explored the ability of these hydrogels to promote chondrocyte viability and cartilage differentiation of stem cells through chemical and mechanical modifications. RESULTS: In vivo and in vitro results demonstrated that the hydrogels exhibited efficient biocompatibility. EPL and PBA modified GelMA hydrogel (Gel-EPL/B) showed stronger activity on chondrocytes compared to the GelMA control group. The Gel-EPL/B group induced the secretion of more extracellular matrix and improved the chondrogenic differentiation potential of stem cells. Finally, thus hydrogel promoted the tissue repair of cartilage defects. CONCLUSION: Modified hydrogel is effective in cartilage tissue repair.

Maxillofacial Injuries in Pediatric Patients.

OBJECTIVE: This study aimed to evaluate and analyse the demographic characteristics and changes in maxillofacial injuries during their development in pediatric patients. METHODS: A retrospective cohort and case-control study was conducted. The sample was composed of all children (less than 10.5 years) who presented with maxillofacial injuries within a 6.5-year period (from December 2012 to April 2019). Data about age, gender, hospitalization date, mechanism of trauma, location and pattern of injuries, associated general injuries or systemic diseases, admission methods (emergency admission or not), type of anesthesia, treatment methods and hospital costs (¥) were recorded and analyzed. Data analysis included Chi-square test, Fisher exact test, and t test. Univariate and multivariate analyses were also performed. Logistic regression analysis was used to control for confounding variables. Differences at P < 0.05 were considered significant. RESULTS: A total of 643 pediatric patients were included in this study, with a boy-to-girl ratio of 1.77:1 (411 boys and 232 girls). The age range was 0.18 to 10.5 years (average of 3.23 ±â€Š1.98 years). The largest age group was patients aged 1 to 2 years (200 patients, 31.1%), followed by 2 to 3 years (139 patients, 21.6%). In the majority of patients, fall at ground level was the most common mechanism of injury (391 patients, 60.8%). In addition, 613 patients (95.3%) sustained at least maxillofacial soft-tissue injuries, while 460 (71.5%) sustained only maxillofacial soft-tissue injuries and 183 (28.5%) sustained maxillofacial fractures. Lip was the most vulnerable soft tissue to be injured (283 patients, 44.0%). Patients who sustained maxillofacial soft-tissue injuries were less prone to maxillofacial fractures than those who did not. Maxillofacial fractures were highly presented in patients with dental injuries (OR = 6.783; 95% confidence interval, 3.147-14.620; P < 0.001). Older children (> 5 years old) were at higher risk of maxillofacial fractures than younger children (≤ 5 years old, P = 0.006). The risk of maxillofacial fractures (except symphysis fractures) increased with age, especially in patients aged between 5 and 10 years. Maxillofacial soft-tissue injuries were highly distributed amongst patients aged 1 to 5 years. The number of patients who sustained only maxillofacial soft-tissue injuries gradually decreased from 2013 to 2018. Patients in emergency admission (OR = 13.375; 95% confidence interval, 1.286-139.121; P = 0.030) and treated under general anesthesia (OR = 27015.375; 95% confidence interval, 1033.046-706484.218; P < 0.001) were more prone to be treated by surgery procedure. Patients with facial fractures were less frequent to be treated by surgery procedure (OR = 0.006; 95% confidence interval, 0.000-0.575; P = 0.028); however, the mandibular symphysis (OR = 18.141; 95% confidence interval, 2.860-115.069; P = 0.002) or body fractures (OR = 71.583; 95% confidence interval, 2.358-2172.879; P = 0.014) were highly treated by surgery procedure. CONCLUSIONS: Maxillofacial fractures in pediatric patients were significantly related to age, etiology, maxillofacial soft-tissue injury, dental injury and other general injuries. Older pediatric patients were at higher risk of maxillofacial fractures (except symphysis fractures) and lower risk of maxillofacial soft-tissue injuries than younger pediatric patients. Patients in emergency admission, fractures of the symphysis or body, and treated under general anesthesia were the main reasons for surgical management.