Periodontal ligament-associated protein-1 knockout mice regulate the differentiation of osteoclasts and osteoblasts through TGF-ß1/Smad signaling pathway.

It has been known that periodontal ligament-associated protein-1 (PLAP-1/Asporin) not only inhibits cartilage formation in osteoarthritis, but it also influences the healing of skull defect. However, the effect and mechanism of PLAP-1/Asporin on the mutual regulation of osteoclasts and osteoblasts in periodontitis are not clear. In this study, we utilized a PLAP-1/Asporin gene knockout (KO) mouse model to research this unknown issue. We cultured mouse bone marrow mesenchymal stem cells with Porphyromonas gingivalis lipopolysaccharide (P.g. LPS) for osteogenic induction in vitro. The molecular mechanism of PLAP-1/Asporin in the regulation of osteoblasts was detected by immunoprecipitation, immunofluorescence, and inhibitors of signaling pathways. The results showed that the KO of PLAP-1/Asporin promoted osteogenic differentiation through transforming growth factor beta 1 (TGF-ß1)/Smad3 in inflammatory environments. We further found the KO of PLAP-1/Asporin inhibited osteoclast differentiation and promoted osteogenic differentiation through the TGF-ß1/Smad signaling pathway in an inflammatory coculture system. The experimental periodontitis model was established by silk ligation and the alveolar bone formation in PLAP-1/Asporin KO mice was promoted through TGF-ß1/Smad3 signaling pathway. The subcutaneous osteogenesis model in nude mice also confirmed that the KO of PLAP-1/Asporin promoted bone formation by the histochemical staining. In conclusion, PLAP-1/Asporin regulated the differentiation of osteoclasts and osteoblasts through TGF-ß1/Smad signaling pathway. The results of this study lay a theoretical foundation for the further study of the pathological mechanism underlying alveolar bone resorption, and the prevention and treatment of periodontitis.

The accuracy and reliability of different midsagittal planes in the symmetry assessment using cone-beam computed tomography.

Symmetry is an essential component of esthetic assessment. Accurate assessment of facial symmetry is critical to the treatment plan of orthognathic surgery and orthodontic treatment. However, there is no internationally accepted midsagittal plane (MSP) for orthodontists and orthognathic surgeons. The purpose of this study was to explore a clinically friendly MSP, which is more accurate and reliable than what is commonly used in symmetry assessment. Forty patients with symmetric craniofacial structures were analyzed on cone-beam computed tomography (CBCT) scans. The CBCT data were exported to the Simplant Pro software to build four reference planes that were constructed by nasion (N), basion (Ba), sella (S), odontoid (Dent), or incisive foramen (IF). A total of 31 landmarks were located to determine which reference plane is the most optimal MSP by comparing the asymmetry index (AI). The mean value of AI showed a significant difference (p < 0.05) among four reference planes. Also, the mean value of AI for all landmarks showed that Plane 2 (consisting of N, Ba, and IF) and Plane 4 (consisting of N, IF, and Dent) were more accurate and stable. In conclusion, the MSP consisting of N, Dent, and IF shows more accuracy and reliability than the other planes. Further, it is more clinically friendly because of its significant advantage in landmarking.

Microplastic pollution differences in freshwater river according to stream order: Insights from spatial distribution, annual load, and ecological assessment.

Microplastic (MP) pollution has become a pressing concern in global freshwater ecosystems because rivers serve as essential channels for the transport of terrestrial debris to the ocean. The current researches mostly focus on the large catchments, but the impact on the small catchments remains underexplored. In this study, we employed Strahler's stream order classification to delineate the catchment structure of the Beijiang River in South China. The distribution pattern of MP contamination and the factors influencing the distribution pattern, were assessed across the streams at different orders. We found that the Beijiang River was moderately polluted compare to other rivers in China, with an average MP abundance of 2.15 ± 1.65 items/L. MP abundance ranged from 3.17 to 1.45 items/L in the streams at different orders, and significantly decreased with increasing stream order (R2 = 0.93). This highlights the key role of small rivers as the channels for the transport of MPs from watersheds to main streams. The high abundance of PP and PE fibers, the high correlation between the stream order and the resin proportion (R2 = 0.89), and the significant correlation between MP abundance and proximity to urban centers (P = 0.02), indicated that MP pollution across the streams at different orders was predominantly influenced by anthropogenic activities, rather than natural environmental factors. By integrating MP data with hydrographic information, the annual MP loads for the streams at Orders 1 to Order 5 were estimated to be 4.63, 39.38, 204.63, 503.06, and 1137.88 tons/yr, respectively. Additionally, an ecological risk assessment indicates that MP pollution led to a low risk in the Beijiang River. Our findings deepen the understanding of MP pollution within freshwater river networks, and emphasize the crucial role of tributary systems in transporting MPs to main river channels.

Further description of the poorly known zooparasitic nematode Abbreviata baltazardi Chabaud, 1953 (Spirurida: Physalopteridae).

Abbreviata baltazardi Chabaud, 1953 (Nematoda: Physalopteridae) is a hitherto poorly known parasitic nematode species reported from Phrynocephalus helioscopus Pallas (Squamata: Agamidae) in Iran. The current knowledge on the morphology of A. baltazardi is still very limited. In the present study, the detailed morphology of A. baltazardi was studied using light microscopy and, for the first time, scanning electron microscopy, based on newly collected specimens from the yarkand toad-headed agama P. axillaris Blanford Pallas (Squamata: Agamidae) in China. Some erroneous or previously unreported morphological features of A. baltazardi were observed using SEM, which include the presence of one large semicircular protrusion and 20-30 denticles on each pseudolabium, the absence of precloacal medioventral papilla in some individuals and the presence of 4-5 postcloacal medioventral papillae in males. SEM observations also clearly showed the detailed morphology of deirids, cloacal ornamentation, caudal papillae, vulva and egg. Abbreviata baltazardi represents the first species of Abbreviata Travassos, 1920 reported in China.

Dual role of endoplasmic reticulum stress-ATF-6 activation in autophagy and apoptosis induced by cyclic stretch in myoblast.

OBJECTIVE: Mandibular growth that is induced by functional appliances is closely associated with skeletal and neuromuscular adaptation. Accumulating evidence has proved that apoptosis and autophagy have a vital role in adaptation process. However, little is known about the underlying mechanisms. This study sought to determine whether ATF-6 is involved in stretch-induced apoptosis and autophagy in myoblast. The study also sought to uncover the potential molecular mechanism. MATERIALS AND METHODS: Apoptosis was assessed by TUNEL and Annexin V and PI staining. Autophagy was detected by transmission electron microscopy (TEM) analysis and immunofluorescent staining for autophagy-related protein light chain 3 (LC3). Real time-PCR and western blot were performed to evaluate the expression level of mRNA and proteins that were associated with endoplasmic reticulum stress (ERS), autophagy and apoptosis. RESULTS: Cyclic stretch significantly decreased the cell viability and induced apoptosis and autophagy of myoblasts time-dependently. Stretching stimuli activated ATF-6 pathway and induced ERS-mediated apoptosis. Moreover, using 4-PBA significantly inhibited ERS-related apoptosis, as well as partially decreasing autophagy. In addition, inhibition of autophagy by 3-MA enhanced apoptosis by affecting the expression of CHOP and Bcl-2. However, it had no obvious effects on ERS-related proteins of GRP78 and ATF-6. More importantly, knockdown ATF-6 effectively weakened apoptosis and autophagy. It did so by regulating the expression of Bcl-2, Beclin1 and CHOP, but not cleaved Caspase-12, LC3II and p62 in stretched myoblast. CONCLUSION: ATF-6 pathway was activated in myoblast by mechanical stretch. ATF-6 may regulate the process of stretch-induced myoblast apoptosis and autophagy via CHOP, Bcl-2 and Beclin1 signaling.

Accuracy of different registration areas using active and passive dynamic navigation systems in dental implant surgery: An in vitro study.

OBJECTIVES: To gauge the relative accuracy of the use of passive and active dynamic navigation systems when placing dental implants, and to determine how registration areas affect the performance of these systems. MATERIALS AND METHODS: Eighty implants were assigned to be placed into 40 total resin mandible models missing either the left or right first molars using either passive or active dynamic navigation system approaches. U-shaped tube registration devices were fixed in the edentulous site for 20 models each on the left or right side. Planned and actual implant positions were superimposed to assess procedural accuracy, and parameters including 3D entry deviation, angular deviation, and 3D apex deviation were evaluated with Mann-Whitney U tests and Wilcoxon signed-rank tests. RESULTS: Respective angular, entry, and apex deviation values of 1.563 ± 0.977°, 0.725 ± 0.268 mm, and 0.808 ± 0.284 mm were calculated for all included implants, with corresponding values of 1.388 ± 1.090°, 0.789 ± 0.285 mm, and 0.846 ± 0.301 mm in the active group and 1.739 ± 0.826°, 0.661 ± 0.236 mm, and 0.769 ± 0.264 mm in the passive group. Only angular deviation differed significantly among groups, and the registration area was not associated with any significant differences among groups. CONCLUSIONS: Passive and active dynamic navigation approaches can achieve comparable in vitro accuracy. Registration on one side of the missing single posterior tooth area in the mandible can complete single-tooth implantation on both sides of the posterior teeth, highlighting the promise of further clinical research focused on this topic.

Tunable and Robust Nanostructuring for Multifunctional Metal Additively Manufactured Interfaces.

Novel processing phenomena coupled with various alloying materials used in metal additive manufacturing (AM) have opened opportunities for the development of previously unexplored micro-/nanostructures. A rationally devised structure nanofabrication strategy of AM surfaces that can tailor the interface morphology and chemistry has the potential for many applications. Here, through an understanding of grain formation mechanisms during AM, we develop a facile method for tuning micro-/nanostructures of one of the most used AM alloys and rationally optimize the morphology for applications requiring low surface adhesion. We demonstrate that optimized AM structures reduce the adhesion of impaling water droplets and significantly delay icing time. The structure can also be altered and optimized for antiflooding jumping-droplet condensation that exhibits significant enhancement in heat transfer performance in comparison to nanostructures formed on conventional Al alloys. In addition to demonstrating the potential of functionalized AM surfaces, this work also provides guidelines for surface-structuring optimization applicable to other AM metals.

Clinical finite element analysis of mandibular displacement model treated with Twin-block appliance.

INTRODUCTION: The mechanical distribution of the mandible is an important factor that affects functional orthosis during Twin-block (TB) appliance correction. Changes in the mandible before and after TB appliance correction are also key factors in maintaining the therapeutic effect. Finite element analysis, a powerful numerical, analytical tool, is widely used to predict the stress and strain distribution of the craniofacial bone that orthodontics generates. METHODS: The sample was a 14-year-old male patient with Class II malocclusion during growth. A cone-beam computed tomography scan was undertaken at pretreatment and posttreatment. In the Finite element analysis of the pretreatment model, the remote displacement model of the mandible was established with the sella point as the center. A mandibular model under TB appliance loading was established. Its mandibular displacement and von Mises stress were compared before and after loading. Three-dimensional registration was conducted on the pretreatment and posttreatment models to measure the sagittal displacement of the centrosome. RESULTS: The force on the mandible occurred mainly in the condyle neck and medial mandible after the TB appliance moved the mandible. After displacement, the posterior upper margin of the condyle was farther away from the articular fossa. Three-dimensional registration results showed that new bone had formed behind and above the condyle after TB appliance treatment. CONCLUSION: The TB appliance provides additional advantages in treating skeletal Class II malocclusions by helping to reduce the burden on the temporomandibular joint and promoting the adaptive reconstruction of the mandible.

Excessive mechanical stress induced temporomandibular joint osteoarthritis via osteoclasts-mediated osteogenic differentiation of BMSCs.

BACKGROUND: Bone homeostasis is a dynamic process maintained by osteoblasts and osteoclasts, which may be regulated by excessive mechanical stress (EMS). OBJECTIVES: Our study aimed to explore the relationship between osteogenic differentiation of BMSCs and EMS-activated osteoclast differentiation of RAW 264.7 cells in order to optimise orthodontic treatment. METHODS: We established the model of EMS in vivo and in vitro. In vivo, HE, Safranin-O staining, micro-CT, and immunofluorescence double-labelling were utilised to assess the changes in condylar, the distributions of osteoblasts, osteoclasts and MAPKs. In vitro, the effects of EMS-activated osteoclast differentiation exerting on osteogenic differentiation of BMSCs were observed by Western Blot, qRT-PCR and Alizarin Red staining. Furthermore, the role of MAPKs in this progress was explored by using inhibitors of MAPKs and co-culture supernatants. RESULTS: In vivo, EMS led to the degradation of condylar cartilage and destruction of subchondral bone, diagnosed as temporomandibular joint osteoarthritis (TMJ OA). Osteoclasts and osteoblasts were both enriched in subchondral bone, but osteoclast predominated. The expressions of p-JNK, p-ERK1/2, and p-p38 were all activated in vitro and in vivo, which were localised mainly in the Trap+ area in subchondral bone. Interestingly, only the inactivation of p-ERK1/2 in osteoclasts significantly inhibited the osteogenic differentiation of BMSCs in vitro. This revealed that p-ERK1/2 played a key role in the osteoclasts-induced osteogenic differentiation of BMSCs. CONCLUSION: Our results proved that EMS led to TMJ OA, in which upregulated p-ERK1/2 in osteoclasts was mechanosensitive and facilitated the osteogenic differentiation of BMSCs.

Chiral Recognition by Flexible Coordination Polymers of Ag+ with a Cysteine-Based Chiral Thiol Ligand That Bears a Binding Site.

We report a new scheme for chiral recognition using coordination polymers of Ag+ with a chiral thiol ligand that contains a binding group. N-Benzoyl-l-cysteine ethyl ester equipped with a boronic acid group at the para position of the phenyl ring forms coordination polymers with Ag+ in alkaline aqueous solutions that exhibit excellent selectivity toward a d-glucose enantiomer over l-glucose, while the coordination polymers from the d-cysteine-based thiol ligand are specific for l-glucose. It is assumed that a conformation change occurs upon interaction of a saccharide molecule with the polymeric chain receptor, for which the next binding is promoted, leading to the highly effective chiral recognition, despite the flexible nature of the polymeric receptor.

Controlling the Periodically Ordered Nanostructures in Ceramics: A Macromolecule-Guided Strategy.

Microscopic structures have a significant influence on the properties of ceramics. The development of macromolecular self-assembly has allowed for control over microscopic structures of ceramics to prepare ceramics with diverse compositions and ordered nanostructures. Herein, recent progress in the preparation of ceramics with periodically ordered nanostructures guided by phase-separated macromolecules are reviewed, which can be summarized as a general strategy termed the "macromolecule-guided strategy." Moreover, two different subcategories, namely, the macromolecule-templated method and the macromolecule-precursor method, are illustrated. In the former method, amphiphilic macromolecules are used as templates to guide the assembly of inorganic species into ordered nanostructures, which are subsequently converted into ceramics; in the latter method, amphiphilic macromolecules containing non-volatile elements are used as the single-source precursors for ordered ceramics. It is believed that the unique diversity and tunable features of macromolecular self-assembly might offer unprecedented opportunities in the development of functional ceramics for various applications.

Influence of life-style factors, including second-hand smoke, on dental caries among 3-year-old children in Wuxi, China.

AIM: To examine the association of life-style factors, including second-hand smoke, with dental caries among 3-year-old children in Wuxi, China. METHODS: A multi-stage stratified random cluster sampling method was used, and 283 children were recruited. The prevalence of dental caries was 29.3% (83/283). RESULTS: Univariate analysis indicated that the possible related factors of dental caries included sleep duration, interest in snacks, candy, exposure to second-hand smoke and weight of birth (all P < 0.05). Meanwhile, multivariate logistic regression analysis suggested that children who had used fluoride were less susceptible to dental caries than those who had not used fluoride before (P < 0.05). Moreover, the risk of dental caries in children who were very interested in snacks was greater than those with little interest in snacks (P < 0.05). CONCLUSIONS: Life-style behaviours are crucial factors and should attract enough attention. There might be a potential negative effect of second-hand smoke on the deciduous caries, but it still requires further studies. A co-ordinated effort by health-care providers, policymakers and health institutions has successfully improved children's oral health and the awareness of hygiene knowledge among citizens in Wuxi city.

Somatosensory changes in Chinese patients after coronectomy vs. total extraction of mandibular third molar: a prospective study.

OBJECTIVES: This study aimed to quantitatively compare the somatosensory function changes of inferior alveolar nerve (IAN) after mandibular third molar extraction with a surgery protocol of coronectomy, as opposed to the conventional method. MATERIALS AND METHODS: Patients with a lower third molar directly contacting IAN were recruited and assigned either to a test group (coronectomy group) or a control group (conventional extraction). A standardized quantitative sensory testing (QST) battery was performed for four times: one week before surgery and the second, seventh, and 28th days after surgery. Z-scores and the loss/gain coding system were applied for each participant. RESULTS: A total of 140 molars (test group: n = 91, control group: n = 49) were enrolled. The sensitivity of the mechanical detection threshold (MDT) and pressure pain threshold (PPT) significantly increased after surgery more than before surgery in both groups (P ≤ 0.001). After the surgery, the sensitivities of the cold detection threshold (CDT), cold pain threshold (CPT), and heat pain threshold (HPT) were significantly higher in the test group than in the control group (P ≤ 0.027). The risk of IANI was significantly larger (P = 0.041) in the test group than in the control group. CONCLUSIONS: QST was a sensitive way to detect somatosensory abnormalities even with no subjective complaint caused by surgery. Coronectomy had less influence on IAN function than conventional total extraction. CLINICAL RELEVANCE: The somatosensory function changes after mandibular third molar extraction were quantitatively studied, and coronectomy was proved a reliable alternation to reduce IAN injury rate.

Repetitive Position Change Improves Gastric Cleanliness for Magnetically Controlled Capsule Gastroscopy.

BACKGROUND AND AIMS: Good gastric preparation is essential for magnetically controlled capsule gastroscopy (MCCG) examination. This study aims to determine if repetitive position change after dimethicone premedication could further improve gastric cleanliness for MCCG. METHODS: Consecutive patients referred for MCCG in our center from May 7 to May 31, 2018 were prospectively enrolled and randomized to undergo repetitive position change for 15 min (position change group) or not (conventional group) after ingesting dimethicone. Primary outcome was gastric cleanliness score and secondary outcomes were detection rate of positive findings, number of lesions per patient, gastric examination time, and safety of MCCG. RESULTS: Totals of 43 and 40 were included in the position change and conventional groups, respectively. Gastric cleanliness score in the position change group was significantly higher than in the conventional group (21.2 ± 1.0 vs. 18.6 ± 2.0, P  < 0.001), as was the proportion of acceptable gastric cleanliness (gastric cleanliness score ≥ 18) (100% vs. 72.5%, P  < 0.001). There was no statistical difference in detection rate of positive findings between the two groups (27.9% vs. 27.5%, P  = 0.97). In the position change group, the gastric examination time was significantly reduced (13.2 ± 4.0 vs. 15.3 ± 5.1, P = 0.043). No adverse events were observed. CONCLUSIONS: Repetitive position change after dimethicone premedication significantly improves gastric cleanliness for MCCG examination. Clinical Trial Registration ClinicalTrials.gov, ID: NCT03514966.

Hydrogen peroxide is a critical regulator of the hypoxia-induced alterations of store-operated Ca2+ entry into rat pulmonary arterial smooth muscle cells.

To investigate the association between store-operated Ca2+ entry (SOCE) and reactive oxygen species (ROS) during hypoxia, this study determined the changes of transient receptor potential canonical 1 (TRPC1) and Orai1, two candidate proteins for store-operated Ca2+ (SOC) channels and their gate regulator, stromal interaction molecule 1 (STIM1), in a hypoxic environment and their relationship with ROS in pulmonary arterial smooth muscle cells (PASMCs). Exposure to hypoxia caused a transient Ca2+ spike and subsequent Ca2+ plateau of SOCE to be intensified in PASMCs when TRPC1, STIM1, and Orai1 were upregulated. SOCE in cells transfected with specific short hairpin RNA (shRNA) constructs was almost completely eliminated by the knockdown of TRPC1, STIM1, or Orai1 alone and was no longer affected by hypoxia exposure. Hypoxia-induced SOCE enhancement was further strengthened by PEG-SOD but was attenuated by PEG-catalase, with correlated changes to intracellular hydrogen peroxide (H2O2) levels and protein levels of TRPC1, STIM1, and Orai1. Exogenous H2O2 could mimic alterations of the interactions of STIM1 with TRPC1 and Orai1 in hypoxic cells. These findings suggest that TRPC1, STIM1, and Orai1 are essential for the initiation of SOCE in PASMCs. Hypoxia-induced ROS promoted the expression and interaction of the SOC channel molecules and their gate regulator via their converted product, H2O2.

Fast magnetic reconstruction of the portal vein with allogeneic blood vessels in canines.

BACKGROUND: The resection and reconstruction of large vessels, including the portal vein, are frequently needed in tumor resection. Warm ischemia before reconstruction might have deleterious effects on the function of some vital organs and therefore, how to reconstruct the vessels quickly after resection is extremely important. The present study was to introduce a new type of magnetic compression anastomosis (MCA) device to establish a quick non-suture anastomosis of the portal vein after resection in canines. METHODS: The new MCA device consists of a pair of titanium alloy and neodymium-ferrum-boron magnet (Ti-NdFeB) composite rings. The NdFeB magnetic ring as a core of the device was hermetically sealed inside the biomedical titanium alloy case. Twelve canines were divided into two groups: a MCA group in which the end-to-end anastomoses was made with a new device after resection in the portal vein and a traditional manual suture (TMS) group consisted of 6 canines. The anastomosis time, anastomotic patency and quality were investigated at week 24 postoperatively. RESULTS: The portal vein was reconstructed successfully in all of the animals and they all survived. The duration of portal vein anastomosis was significantly shorter in the MCA group than in the TMS group (8.16+/-1.25 vs 36.24+/-2.17 min, P<0.05). Portography and ultrasound showed that the blood flow was normal without angiostenosis or thrombosis in all of the canines. Hematoxylin-eosin staining and electron microscope scanning showed in contrast to the TMS group, MCA anastomotic intimal was much smoother with more regularly arranged endothelial cells at week 24 postoperatively. CONCLUSIONS: The Ti-NdFeB composite MCA device was applicable in reconstruction of large vessels after resection. This device was easy to use and the anastomosis was functionally better than the traditional sutured anastomosis.

Surface enhanced fluorescence from silver film substrate decorated with nanohole arrays.

The fluorescence enhancement effect of Rh6G molecules deposited on the silver film substrate decorated with nanohole arrays was investigated in this paper. The prepared substrate, decorated with nanohole arrays, was fabricated with the deposition of silver films onto the anodic aluminum oxide templates through magnetron sputtering method. Compared with the conventional continuous silver film substrate, the prepared substrate shows better enhanced effect. Particularly, the fluorescence enhancement factor has a relationship with the size and period of the nanohole arrays. The experimental observations were analyzed with local surface plasmon resonance model. The results of current work highlight the importance of strong electromagnetic coupling effect in surface enhanced fluorescence.

Decompression as a treatment for odontogenic cystic lesions of the jaw.

PURPOSE: To evaluate the effectiveness of decompression as the primary treatment of odontogenic cystic lesions of the jaw involving factors that affect relative shrinking speed and bone regeneration. PATIENTS AND METHODS: A total of 32 patients with odontogenic cystic lesions of the jaw underwent decompression with customized thermoplastic resin stents. Clinical examinations and pre- and postdecompression panoramic radiographs were analyzed. RESULTS: The mean relative speed of shrinkage of radicular cysts (RCs; 3.37 cm(2)/month) was faster than those of keratocystic odontogenic tumors (KCOTs; 2.87 cm(2)/month) and unicystic ameloblastomas (UABs; 2.71 cm(2)/month). The relative shrinking size increased linearly in a time-dependent manner for KCOTs (r = 0.849, P < .001), RCs (r = 0.681, P = .319), and UABs (r = 0.146, P = .730); a similar relation was detected between the primary radiolucent area of cystic lesions before decompression and relative shrinking speed after decompression in KCOTs (r = 0.481, P = .032), RCs (r = 0.260, P = .673), and UABs (r = 0.370, P = .366), but patient age did not affect the relative speed of shrinkage (P > .05). Furthermore, the increase in bone density was more significant in RCs than in KCOTs (P = .026) and UABs (P = .012) after decompression. CONCLUSION: Decompression was effective in reducing odontogenic cystic lesions of the jaw and increasing bone density. For aggressive lesions, secondary definitive surgery was necessary.

[Risk factors for death in children with severe hand, foot and mouth disease].

OBJECTIVE: To study the death risk factors in children with severe hand, foot and mouth disease (HFMD). METHODS: A total of 164 children with severe HFMD between May 2010 and September 2012 were recruited and classified into death and survival groups according to their prognosis. The differences in general information, clinical signs and symptoms and laboratory examinations were compared between the two groups. The multivariate logistic regression analysis was used to identify death risk factors in children with severe HFMD. RESULTS: There were significant differences in the incidences of atypical rash, persistent fever, dyspnea, pulmonary hemorrhage, heart rate increase, blood pressure abnormalities, cold sweat, capillary refill time>3 seconds and frequent seizures, and blood glucose, serum creatine kinase and serum lactate levels between the death and the survival groups (P<0.05). The multivariate logistic regression analysis showed three independent death risk factors for children with severe HFMD: pulmonary hemorrhage (OR=9.466, 95%CI: 1.786-21.256), abnormal blood pressure (OR=5.224, 95%CI: 1.012-28.985) and elevated serum lactate level (OR=2.154, 95%CI: 1.020-8.253). CONCLUSIONS: Pulmonary hemorrhage, abnormal blood pressure and elevated serum lactate are major death risk factors for children with severe HFMD.

Evaluating stress and displacement in the craniomandibular complex using Twin Block appliances at varied angles: A finite element study.

OBJECTIVES: The objective of this investigation was to assess the stress and displacement pattern of the craniomandibular complex by employing finite element methodology to simulate diverse angulations of inclined planes that are incorporated in the Twin Block appliance. METHODS: A 3D finite element representation was established by use of Cone Beam Computed Tomography (CBCT) scans. This comprehensive structure included craniofacial skeletal components, the articular disc, a posterior disc elastic layer, dental elements, periodontal ligaments, and a Twin Block appliance. This investigation is the first to incorporated inclined planes featuring three distinct angulations (45, 60, and 70°) as the study models. Mechanical impacts were evaluated within the glenoid fossa, tooth, condylar, and articular disc regions. RESULTS: In all simulations, the stress generated by the Twin Block appliance was distributed across teeth and periodontal ligament, facilitating the anterior movement of mandibular teeth and the posterior displacement of maxillary teeth. Within the temporomandibular joint region, compressive forces on the superior and posterior facets of the condyle diminished, coinciding with the stress configuration that fosters condylar and mandibular growth. Stress dispersion homogenized in the condylar anterior facet and articular disc, with considerable tensile stress in the glenoid fossa's posterior aspect conforming to stress distribution that promote fossa reconfiguration. The 70° inclined plane exerts the highest force on the tissues. The condyle's maximum and minimum principal stresses are 0.36 MPa and -0.15 MPa, respectively, while those of the glenoid fossa are 0.54 MPa and -0.23 MPa. CONCLUSION: Three angled appliances serve the purpose of advancing the mandible. A 45° inclined plane relative to the occlusal plane exerts balanced anteroposterior and vertical forces on the mandibular arch. Steeper angles yield greater horizontal forces, which may enhance forward growth and efficient repositioning.