Molecularly imprinted polymer-coated silica microbeads for high-performance liquid chromatography.

Molecularly imprinted polymer (MIP)-based chromatographic separation materials, owing to their advantages of unique selectivity, low cost, suitable reproducibility, and acceptable stability, have attracted a great deal of research in different fields. In this investigation, a new type of MIP-coated silica (MIP/SiO2) separation material was developed using sulfamethoxazole as a template; the specific recognition ability of MIP and appropriate physicochemical properties (abundant Si-OH, suitable pore structure, good stability, etc.) of SiO2 microbeads were combined. The MIP/SiO2 separation materials were characterized carefully. Then, various compounds (such as sulfonamides, ginsenosides, nucleosides, and several pesticides) were used to comprehensively evaluate the chromatographic performances of the MIP/SiO2 column. Furthermore, the chromatographic performances of the MIP/SiO2 column were compared with those of other separation materials (such as non-imprinted polymer-coated silica, C18/SiO2, and bare silica) packed columns. The resolution value of all measured compounds was more than 1.51. The column efficiencies of 13 510 plates per meter (N m-1) for sulfamethoxazole, 11 600 N m-1 for ginsenoside Rd, and 10 510 N m-1 for 2'-deoxyadenosine were obtained. The acceptable results verified that the MIP/SiO2 column can be applied to separate highly polar drugs such as sulfonamides, ginsenosides, nucleosides, and pesticides.

Customized planning of the visible maxillary arch width in harmony with interparopia width and smile width for female facial aesthetics.

BACKGROUND: The visible maxillary arch width (VAW) is an important aesthetic-determining feature. To date, there is no well-established methodology to determine the aesthetically optimal VAW in customized treatment planning. METHODS: In this study, the common traits of the dentofacial configuration were investigated in most attractive Asian and Caucasian female smiles. The smiling photo of a subject was digitally modified based on combined variations of VAW, smile width (SW), transverse facial dimensions (TFD), and vertical facial dimensions. These modified photos were assessed for aesthetics. The aesthetically essential parameters were identified, and their mathematic correlations and reference ranges were determined for different vertical facial patterns. Using the obtained results, a mathematic guidance was constructed for customized smile designing. The applicability of this guidance was tested in Asian females. RESULTS: The most attractive Asian and Caucasian female smiles have intraracial and interracial commonalities in the VAW-to-TFD ratios. The interparopia width (IPD) predominated over facial widths in determining well-matched VAW and SW. For optimal smile aesthetics, the VAW and SW were correlated as simulated by the formula 1.92 IPD ≤ VAW + 2.3 SW ≤ 2.17 IPD, plus the VAW-to-IPD ratio within 0.54 to 0.62 and the SW-to-IPD ratio within 0.61 to 0.71, ranges tailored to vertical facial patterns. This constitutes a mathematic guidance for customized planning of the aesthetically optimal VAW. This guidance was preliminarily validated to be applicable to Asian females. CONCLUSIONS: The VAW-to-TFD ratios were essential for Caucasian and Asian female smile aesthetics. The mathematic guidance could serve as a reference for customized smile designs for Asian females.

Clinical Research on Rett Syndrome: Central Hypoxemia and Hypokalemic Metabolic Alkalosis.

Background: Rett syndrome (RTT) is now widely recognized as a profound neurological disorder that predominantly affects females and is closely associated with mutations in the methylated CpG binding protein 2 (MECP2) gene located on the X chromosome. The Characteristic symptoms of RTT include the loss of acquired language and motor skills, repetitive hand movements, irregular breathing, and seizures. Additionally, RTT patients may experience sporadic episodes of gastrointestinal problems, hypoplasia, early-onset osteoporosis, bruxism, and screaming episodes. It is worth noting that males exhibit a unique and variable phenotype, though rare in RTT cases, often accompanied by severe manifestations. Case Presentation: In this report, we present the case of a young male child with a de novo c.806delG hemizygous mutation, leading to an atypical presentation of RTT that remarkably mirrors the clinical features of Bartter syndrome, a genetic metabolic disorder. The clinical manifestations in this case included the loss of previously acquired language and motor skills, repetitive hand movements, breathing irregularities, seizures, sporadic episodes of gastrointestinal distress, hypoplasia, early-onset osteoporosis, bruxism, and episodes of screaming. This distinctive presentation underscores the complex diagnostic landscape of RTT, particularly in males, and highlights the need for vigilant clinical evaluation. Conclusions: This case report sheds light on an unusual and atypical presentation of RTT in a young male child with a de novo c.806delG hemizygous mutation. The resemblance of clinical features to Bartter syndrome underscores the diagnostic challenges posed by RTT and highlights the importance of comprehensive clinical assessment and genetic testing, especially in cases deviating from the typical RTT phenotype. Our findings contribute valuable insights into the early diagnosis and management of atypical RTT presentations.

Forensic validation of a combined analysis of mRNA and miRNA markers for precise tissue origin inferences of five kinds of body fluids by RT-qPCR.

Correctly inferring the tissue origin types of forensic-relevant body fluids left at a crime scene is beneficial for reconstructing a crime scene. However, it is still a challenge to accurately identify different kinds of body fluids at a crime scene. Shorter sequence length and anti-degradation microRNA (miRNA) can be used to infer the tissue sources of biological fluid traces, but a limited number of miRNAs are tissue specific. The application of messenger RNA (mRNA) has been confirmed by different studies based on its high tissue specificity. According to the differential expression features of mRNA or miRNA in forensically relevant body fluids, this study developed a simultaneously reversed mRNA and miRNA system and then used these two types of RNAs for the determinations of five common kinds of body fluids. Compared with previously reported single kind of mRNA or miRNA assay, the combined mRNA and miRNA system showed good advantages for human body fluid identifications, especially it could be applied in mixed samples. In conclusion, the obtained results indicated that this combined mRNA and miRNA system might provide a scientific and accurate reference for body fluid identifications.

A Novel Anderson-Type POMs-Based Hybrids Flame Retardant for Reducing Smoke Release and Toxicity of Epoxy Resins.

Smoke emission and smoke toxicity have drawn more attention to improving the fire safety of polymers. In this work, a polyoxometalates (POMs)-based hybrids flame retardant (P-AlMo6 ) epoxy resin (EP) is prepared with toxicity-reduction and smoke-suppression properties via a peptide coupling reaction between POMs and organic molecules with double DOPO (bisDOPA). It combines the good compatibility of the organic molecule and the superior catalytic performance of POMs. Compared to pure EP, the glass transition temperature and flexural modulus of EP composite with 5 wt.% P-AlMo6 (EP/P-AlMo6 -5) are raised by 12.3 °C and 57.75%, respectively. Notably, at low flame-retardant addition, the average CO to CO2 ratio (Av-COY/Av-CO2 Y) is reduced by 33.75%. Total heat release (THR) and total smoke production (TSP) are lowered by 44.4% and 53.7%, respectively. The Limited Oxygen Index (LOI) value achieved 31.7% and obtained UL-94 V-0 rating. SEM, Raman, X-ray photoelectron spectroscopy, and TG-FTIR are applied to analyze the flame-retardant mechanism in condensed and gas phase. Outstanding flame retardant, low smoke toxicity properties are attained due to the catalytic carbonization ability of metal oxides Al2 O3 and MoO3 produced from the breakdown of POMs. This work advances the development of POMs-based hybrids flame retardants with low smoke toxicity properties.

A Comprehensive Analysis of Clinical Crowns in Young of Han Nationality with Normal Occlusion Using Intraoral Scanning.

Background: The measurement and analysis of clinical crowns play a crucial role in stomatology, anthropology, and studies of genetic and environmental variables in oral and maxillofacial development. Purpose: The objective of the present study was to measure the parameters of clinical crowns of permanent dentition in youth of Han nationality using intraoral scanning and identify potential influencing factors. Materials and Methods: A total of 100 subjects (50 males and 50 females) of Han nationality aged 18-24 with normal occlusion were selected. An intraoral scanner was used to obtain the digital dental impressions, and Materialise Magics 21 software was used to measure the mesiodistal diameter (MDD), buccolingual diameter (BLD), height, mesiodistal angle (MDA), and vestibulo-oral angle (VOA) of clinical crowns. The central height was calculated based on the height of clinical crowns. SPSS 27.0 software was used for statistical analysis. The two-independent-samplet-test was used to assess discrepancies in clinical crowns between males and females. The paired t-test was used to determine differences between antimetric pairs of clinical crowns within the same arch. The repeatability of intraoral scanning was tested using the paired t-test between two measurements at one-month intervals. The overall estimated effect was considered significant where P < 0.05. Results: The MDD, BLD, height, MDA, and VOA of clinical crowns in the youth of Han nationality were measured, and the central height was calculated. No significant difference was found in terms of MDA and VOA between genders and antimetric pairs within the same arch. Regarding the distance parameters, the MDD, BLD, and height of clinical crowns in males were significantly larger than those in females (MDD: U1, U3, U7, L2, L3, L6, and L7: P < 0.01; BLD: U1: P=0.02; U3-U7 and L1-L7: P < 0.01; height: U2: P=0.03; and U1, U3-U7, and L3-L7: P < 0.01). No significant difference was found in clinical crowns between antimetric pairs within the same arch. Intraoral scanning demonstrated good repeatability in the measurement of clinical crowns. Conclusions: Apart from MDA and VOA, the parameters of clinical crowns in males were significantly larger than in females. Antimetric pairs of clinical crowns within the same arch demonstrated similar tooth dimensions. In future clinical practice and scientific research in the oral and maxillofacial region, a comprehensive design of sexual and ethnic characteristics should be considered.

Micro-matrix cartridge extraction followed by online micro-solid phase extraction based on polystyrene@hydroxypropyl-ß-cyclodextrin nanofibers for selective determination of fipronil and its metabolites in soil.

Micro-matrix cartridge extraction coupled on-line to micro-solid phase extraction-high performance liquid chromatography-mass spectrometry (µ-MCE-online-µ-SPE-HPLC-MS) is presented. Micro-matrix cartridge extraction (µ-MCE) was applied to highly efficient desorption of adsorbed pesticides from contaminated soil with favorable extraction efficiency (100%). Novel polystyrene@hydroxypropyl-ß-cyclodextrin (PS@HPCD) electrospun nanofibers with 3D network structure were prepared to selectively capture fipronil and its metabolites. High selectivity was obtained with adsorption efficiency ≥ 86.64% via complexation, hydrophobic affinity, and π-π interactions. PS@HPCD nanofibers exhibited remarkable advantages such as excellent enrichment factors (24-55), superior permeability, and long service life (> 65 times). Under the optimum conditions, wide linear range (0.1-1000 ng g-1), low detection limits (0.0032-0.0067 ng g-1), high recoveries (84-124.5%), favorable repeatability (RSD ≤ 10.4%, n = 5), and reproducibility (RSD ≤ 7.2%, n = 3) were acquired for fipronil and three metabolites. The developed method was applied to the pesticide determination in actual soils and the ISO-certified soil with satisfactory recoveries (96.5%). The method developed provides a green, efficient, and miniaturized method for the determination of trace pesticide residues in soil.

Specific capture and determination of glycoprotein using a hybrid epitopes and monomers-mediated molecular-imprinted polymer enzyme-free electrochemical biosensor.

A novel molecular-imprinted polymer (MIP)-based enzyme-free biosensor was created for the selective detection of glycoprotein transferrin (Trf). For this purpose, MIP-based biosensor for Trf was prepared by electrochemical co-polymerization of novel hybrid monomers 3-aminophenylboronic acid (M-APBA) and pyrrole on a glassy carbon electrode (GCE) modified with carboxylated multi-walled carbon nanotubes (cMWCNTs). Hybrid epitopes of Trf (C-terminal fragment and glycan) have been selected as templates. The produced sensor exhibited great selective recognition ability toward Trf under optimal preparation conditions, offering good analytical range (0.125-1.25 µM) with a detection limit of 0.024 µM. The proposed hybrid epitope in combination with hybrid monomer-mediated imprinting strategy was successfully applied to detect Trf in spiked human serum samples, with recoveries and relative standard deviations ranging from 94.7 to 106.0% and 2.64 to 5.32%, respectively. This study provided a reliable protocol for preparing hybrid epitopes and monomers-mediated MIP for the synergistic and effective determination of glycoprotein in complicated biological samples.

Effect of offset on the precision of 3D-printed orthognathic surgical splints.

OBJECTIVE: This study evaluated the effect of offset on the precision of three-dimensional (3D)-printed splints, proposing to optimize the splint design to compensate for systematic errors. MATERIALS AND METHODS: 14 resin model sets were scanned and offset as a whole by given distances (0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, and 0.40 mm). Intermediate splints (ISs) and final splints (FSs) were generated from the non-offset and offset models and grouped correspondingly, named as splint type-offset value, IS-0.05, for instance. Dentitions occluded with the splint were scanned. Translational and rotational deviations of the lower dentition relative to the upper dentition were 3D measured. RESULTS: Deviations of ISs and FSs were more evident in the vertical and pitch dimensions, and were mostly acceptable in other dimensions. ISs with offset ≥ 0.05 mm showed vertical deviations significantly below 1 mm (P < 0.05) while ISs with 0.10- to 0.30-mm offsets had pitch rotations significantly lower than 1° (P < 0.05). The Pitch of IS-0.35 was significantly larger than ISs with 0.15- to 0.30-mm offsets (P < 0.05). Meanwhile, FSs fit better as the offset increased and FSs with offsets ≥ 0.15 mm all had deviations significantly lower than 1 mm (for translation) or 1° (for rotation) (P < 0.05). CONCLUSIONS: Offset affects the precision of 3D-printed splints. Moderate offset values of 0.10 to 0.30 mm are recommendable for ISs. Offset values ≥ 0.15 mm are recommended for FSs in cases with stable final occlusion. CLINICAL RELEVANCE: This study found the optimal offset ranges for 3D-printed ISs and FSs via a standardized protocol.

XGBoost-aided prediction of lip prominence based on hard-tissue measurements and demographic characteristics in an Asian population.

INTRODUCTION: Prediction of lip prominence based on hard-tissue measurements could be helpful in orthodontic treatment planning and has been challenging and formidable thus far. METHODS: A machine learning-based cross-sectional study was conducted on 1549 patients. Hard-tissue measurements and demographic information were used as the input features. Seven popular machine learning algorithms were applied to the datasets to predict upper and lower lip prominence. The algorithm that performed the best was selected for the construction of the prediction model. Evaluation of feature importance was conducted using 3 classical methods. RESULTS: Among the 7 algorithms, the XGBoost model performed the best in the prediction of the distances between labrale superius or labrale inferius to the esthetics plane (UL-EP and LL-EP distances), with root mean square error values of 1.25, 1.49 and r2 values of 0.755 and 0.683, respectively. Among the 14 input features, the L1-NB distance contributed the most to the prominences of the upper and lower lips. A lip prominence predictor was developed to facilitate clinical application by deploying the prediction model into a downloadable tool kit. CONCLUSIONS: The XGBoost model performed well with high accuracy and practicability in predicting upper and lower lip prominence. The artificial intelligence-aided predictor could serve as a reference for orthodontic treatment planning.

Identification and validation of m6A RNA regulatory network in pulpitis.

BACKGROUND: N6-methyladenosine (m6A) RNA modification regulators play an important role in many human diseases, and its abnormal expression can lead to the occurrence and development of diseases. However, their significance in pulpitis remains largely unknown. Here, we sought to identify and validate the m6A RNA regulatory network in pulpitis. METHODS: Gene expression data for m6A regulators in human pulpitis and normal pulp tissues from public GEO databases were analyzed. Bioinformatics analysis including Gene ontology (GO) functional, and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were performed by R package, and Cytoscape software was used to study the role of m6A miRNA-mRNA regulatory network in pulpitis. Quantitative real-time PCR (qRT-PCR) was performed to validate the expression of key m6A regulators in collected human pulpitis specimens. RESULTS: Differential genes between pulpitis and normal groups were found from the GEO database, and further analysis found that there were significant differences in the m6A modification-related genes ALKBH5, METTL14, METTL3, METTL16, RBM15B and YTHDF1. And their interaction relationships and hub genes were determined. The hub m6A regulator targets were enriched in immune cells differentiation, glutamatergic synapse, ephrin receptor binding and osteoclast differentiation in pulpitis. Validation by qRT-PCR showed that the expression of methylases METTL14 and METTL3 was decreased, thus these two genes may play a key role in pulpitis. CONCLUSION: Our study identified and validated the m6A RNA regulatory network in pulpitis. These findings will provide valuable resource to guide the mechanistic and therapeutic analysis of the role of key m6A modulators in pulpitis.

Bioheterojunction-Engineered Polyetheretherketone Implants With Diabetic Infectious Micromilieu Twin-Engine Powered Disinfection for Boosted Osteogenicity.

Diabetic infectious micromilieu (DIM) leads to a critical failure rate of osseointegration by virtue of two main peculiarities: high levels of topical glucose and inevitable infection. To tackle the daunting issue, a bioheterojunction-engineered orthopedic polyetheretherketone (PEEK) implant consisting of copper sulfide/graphene oxide (CuS/GO) bioheterojunctions (bioHJs) and glucose oxidase (GOx) is conceived and developed for DIM enhanced disinfection and boosted osseointegration. Under hyperglycemic micromilieu, GOx can convert surrounding glucose into hydrogen peroxide (H2 O2 ). Then, upon infectious micromilieu, the bioHJs enable the catalyzation of H2 O2 to highly germicidal hydroxyl radical (·OH). As a result, the engineered implants massacre pathogenic bacteria through DIM twin-engine powered photo-chemodynamic therapy in vitro and in vivo. In addition, the engineered implants considerably facilitate cell viability and osteogenic activity of osteoblasts under a hyperglycemic microenvironment via synergistic induction of copper ions (Cu2+ ) and GO. In vivo studies using bone defect models of diabetic rats at 4 and 8 weeks further authenticate that bioHJ-engineering PEEK implants substantially elevate their osseointegration through biofilm elimination and vascularization, as well as macrophage reprogramming. Altogether, the present study puts forward a tactic that arms orthopedic implants with DIM twin-engine powered antibacterial and formidable osteogenic capacities for diabetic stalled osseointegration.

Development of Biodegradable Osteopromotive Citrate-Based Bone Putty.

The burden of bone fractures demands development of effective biomaterial solutions, while additional acute events such as noncompressible bleeding further motivate the search for multi-functional implants to avoid complications including osseous hemorrhage, infection, and nonunion. Bone wax has been widely used in orthopedic bleeding control due to its simplicity of use and conformation to irregular defects; however, its nondegradability results in impaired bone healing, risk of infection, and significant inflammatory responses. Herein, a class of intrinsically fluorescent, osteopromotive citrate-based polymer/hydroxyapatite (HA) composites (BPLP-Ser/HA) as a highly malleable press-fit putty is designed. BPLP-Ser/HA putty displays mechanics replicating early nonmineralized bone (initial moduli from ≈2-500 kPa), hydration induced mechanical strengthening in physiological conditions, tunable degradation rates (over 2 months), low swelling ratios (<10%), clotting and hemostatic sealing potential (resistant to blood pressure for >24 h) and significant adhesion to bone (≈350-550 kPa). Simultaneously, citrate's bioactive properties result in antimicrobial (≈100% and 55% inhibition of S. aureus and E. coli) and osteopromotive effects. Finally, BPLP-Ser/HA putty demonstrates in vivo regeneration in a critical-sized rat calvaria model equivalent to gold standard autograft. BPLP-Ser/HA putty represents a simple, off-the-shelf solution to the combined challenges of acute wound management and subsequent bone regeneration.

Inhibition of osteoclastogenesis by interleukin-33 administration in the periodontal ligament under mechanical loading.

BACKGROUND AND OBJECTIVES: The molecular mechanisms mediating external root resorption are poorly understood. Interleukin-33 (IL-33) expression increased remarkably in the periodontal ligament (PDL) under orthodontic loading. The IL-33-driven responses are delicately cell type- and tissue context-dependent. It is unknown how IL-33 act on osteoclastogenesis in the context of root surface. This study aimed to investigate the effect of IL-33 on osteoclastogenesis in the PDL under mechanical loading. MATERIALS AND METHODS: C57BL/6J mice were treated with injections of phosphate buffer saline (PBS) or recombinant mouse IL-33 (rmIL-33, 6 µl, 30 µg/ml), and subjected to models of orthodontic tooth movement. Tartrated resistant acid phosphates (TRAP)-positive cells and IL-33 expressions were examined in the PDL. IL-33 release from human PDL cells (hPDLCs) was detected by ELISA. Cementoblast-like (OCCM-30) cells were cultured in the presence of rmIL-33 to examine the release of osteoclast-regulatory proteins. The effects of rmIL-33 on osteoclastogenesis were examined in vitro in cultures of bone marrow macrophages (BMMs) and in BMMs-OCCM-30 cocultures. Expressions of osteoclast-specific or -related genes and proteins were investigated in BMMs-OCCM-30 cocultures treated with or without rmIL-33, in the presence or absence of granulocyte-macrophage colony-stimulating factor (GM-CSF) neutralizing antibody. RESULTS: Interleukin-33 expressions were upregulated in the PDL under orthodontic loading. Static compressive force enhanced expression and release of IL-33 from hPDLCs. Administration of rmIL-33 resulted in reduced number of TRAP-positive cells in the PDL, and inhibited osteoclast differentiation from BMMs in vitro. OCCM-30 cells had varied osteoprotegerin (OPG) / receptor activator for nuclear factor-κB ligand (RANKL) secretion and increased release of GM-CSF under rmIL-33 stimulation. Treatment with rmIL-33 in BMMs-OCCM-30 cocultures resulted in inhibited differentiation and decreased activity of osteoclasts, and these effects were partially reversed by GM-CSF neutralizing antibody. CONCLUSIONS: Interleukin-33 inhibits osteoclastogenesis in the PDL under orthodontic loading. The anti-osteoclastogenic effects were mediated partly by directly affecting osteoclast precursors and partly by cementoblast-mediated release of GM-CSF.

Effects of BMAL1 on dentinogenic differentiation of dental pulp stem cells via PI3K/Akt/mTOR pathway.

AIM: This study aimed to investigate the effect of the circadian clock gene Bmal1 on dentinogenic differentiation of dental pulp stem cells (DPSCs) under inflammatory conditions. METHODOLOGY: Dental pulp stem cells were isolated from the pulp tissue of the healthy donor and were then stimulated with different concentrations of lipopolysaccharide (LPS) to mimic inflammatory conditions. Real-time polymerase chain reaction was used to detect the gene expression of circadian clock genes Bmal1, Clock, Per1, Per2, Cry1, and Cry2. Western blot (WB) was applied to analyse the protein expression of circadian clock proteins (BMAL1, CLOCK) and dentinogenic differentiation-related proteins (DSPP, DMP1). In addition, the apoptosis and osteogenic differentiation of DPSCs were also analysed in the presence of different concentrations of LPS. RESULTS: The expression of circadian clock genes of DPSCs significantly changed in an inflammatory environment. WB analysis shows that BMAL1 is relevant to the dentinogenic differentiation of DPSCs. In low concentrations of LPS-mimicked inflammatory conditions, the expression of BMAL1 increased and promoted the dentinogenic differentiation of DPSCs. However, under high concentrations of LPS-mimicked inflammatory conditions, the expression of BMAL1 decreased and inhibited the dentinogenic differentiation of DPSCs. Moreover, the effects of BMAL1 on dentinogenic differentiation of DPSCs may be through PI3K/Akt/mTOR pathway. CONCLUSIONS: This study showed that the circadian clock gene Bmal1 affected dentinogenic differentiation of DPSCs, providing a new insight for clinical stem cell-based restorative dentinogenesis therapies.

The lower bow-shaped curve as a novel reference frame to determine the lateral limit of the maxillary anterior arch for smile esthetics.

INTRODUCTION: Smile analysis in horizontally angled views is indispensable for esthetic assessment and could reveal teeth-to-lip disharmony, which might escape discovery in the frontal and profile views. However, evidence is lacking on where the anterior teeth should be positioned for esthetics in angled smiles. METHODS: Based on 3-dimensional facial image processing and geometric analysis, the lip edges were projected to the horizontal plane, and the horizontal teeth-to-lip relation was simplified and represented by the distances from dental landmarks to lower bow-shaped curves (LBSC), with the distance from facial-axis (FA) point of the canine to LBSC (FA-tangent line [TL] distance) identified as the key parameter. Using photographic modification and esthetic assessment, the effect of FA-TL distances on the attractiveness of 45° angled smiles was tested, with esthetic ranges identified. A simplified method was developed to obtain the estimative LBSC and FA-TL distances using 2-dimensional photographs and geometric analysis to facilitate clinical application. RESULTS: The FA-TL distance remarkably affected the esthetics of 45° angled smiles. Smiles were attractive when the FA-TL distance ranged from -1.0 to 1.5 mm perceived by orthodontists and from -1.5 to 1.5 mm perceived by laypersons. The 2-dimensional photograph-derived estimative FA-TL distance was not significantly different from that obtained in a 3-dimensional image, validating the simplified method. CONCLUSIONS: The LBSC could serve as a reference frame to determine the lateral limit of the maxillary anterior arch for the esthetics of 45° angled smiles. The FA-TL distance, which represented the spatial relation of the maxillary canine with the lower lip, was an esthetically essential parameter. For females aged 20-30 years, the FA point of the maxillary canines should be positioned no more than 1.5 mm labial or lingual to the LBSC.

Integrating maxillary dentition and 3D facial photo using a modified CAD/CAM facebow.

BACKGROUND: Accurate integration of the dentitions with the face is essential in dental clinical practice. Here we introduce a noninvasive and efficient protocol to integrate the digitized maxillary dentition with the three-dimensional (3D) facial photo using a prefabricated modified computer-aided design/computer-aided manufacture (CAD/CAM) facebow. METHODS: To integrate the maxillary dentition with the 3D facial photo, the CAD/CAM facebow protocol was applied to 20 patients by taking a series of 3D facial photos in the clinic and integrating them in the laboratory. The integration accuracy of this protocol was compared with that of a valid 3D computed tomography (CT)-aided protocol concerning translational deviations of the landmarks representing maxillary incisors and maxillary first molars as well as the rotational deviation of the maxillary dentition. The intra- and inter-observer reproducibility was assessed, and the time of clinical operation and laboratory integration was recorded. RESULTS: This facebow-aided protocol generated 3D fused images with colored faces and high-resolution dentitions, and showed high reproducibility. Compared with the well-established CT-aided protocol, the translational deviations ranged from 0 to 1.196 mm, with mean values ranging from 0.134 to 0.444 mm, and a relatively high integration error was found in the vertical dimension (Z) with a mean ± standard deviation (SD) of 0.379 ± 0.282 mm. Meanwhile, the rotational deviations ranged from 0.020 to 0.930°, with mean values less than 1°, and the most evident deviation was seen in pitch rotation with a mean ± SD of 0.445 ± 0.262°. The workflow took 4.34 ± 0.19 min (mins) for clinical operation and 11.23 ± 0.29 min for laboratory integration. CONCLUSION: The present radiation-free protocol with the modified CAD/CAM facebow provided accurate and reproducible transfer of the digitized maxillary dentition to the 3D facial photo with high efficiency.

Effect of occlusal coverage depths on the precision of 3D-printed orthognathic surgical splints.

BACKGROUND: Precise orthognathic surgical splints are important in surgical-orthodontic treatment. This study aimed to propose a standardized protocol for three-dimensional (3D)-printed splints and assess the precision of splints with different occlusal coverage on the dentition (occlusal coverage depth, OCD), thus optimizing the design of 3D-printed splints to minimize the seemingly unavoidable systematic errors. METHODS: Resin models in optimal occlusion from 19 patients were selected and scanned. Intermediate splints (ISs) and final splints (FSs) with 2-mm, 3-mm, 4-mm, and 5-mm OCDs were fabricated and grouped as IS-2, IS-3, IS-4, IS-5, FS-2, FS-3, FS-4, and FS-5, respectively. The dentitions were occluded with each splint and scanned as a whole to compare with the original occlusion. Translational and rotational deviations of the lower dentition and translational deviations of the landmarks were measured. RESULTS: For vertical translation, the lower dentitions translated inferiorly to the upper dentition in most of the splints, and the translation increased as OCD got larger. Vertical translations of the dentitions in 89.47% of IS-2, 68.42% of IS-3, 42.11% of IS-4, 10.53% of IS-5, 94.74% of FS-2, 63.16% of FS-3, 26.32% of FS-4, and 21.05% of FS-5 splints were below 1 mm, respectively. For pitch rotation, the lower dentitions rotated inferiorly and posteriorly in most groups, and the rotation increased as OCD got larger. Pitch rotations of the dentitions in 100% of IS-2, 89.47% of IS-3, 57.89% of IS-4, 52.63% of IS-5, 100.00% of FS-2, 78.95% of FS-3, 52.63% of FS-4, and 47.37% of FS-5 splints were below 2°, respectively. On the other hand, the transversal and sagittal translations, roll and yaw rotations of most groups were clinically acceptable (translation < 1 mm and rotation < 2°). The deviations of ISs and FSs showed no statistical significance at all levels of coverage (P > 0.05). CONCLUSIONS: A protocol was proposed to generate 3D-printed ISs and FSs with normalized basal planes and standardized OCDs. Deviations of the ISs and FSs were more evident in the vertical dimension and pitch rotation and had a tendency to increase as the OCD got larger. ISs and FSs with both 2-mm and 3-mm OCD are recommendable regarding the precision relative to clinical acceptability. However, considering the fabrication, structural stability, and clinical application, ISs and FSs with 3-mm OCD are recommended for accurate fitting.

Investigation of health risk assessment and odor pollution of volatile organic compounds from industrial activities in the Yangtze River Delta region, China.

To investigate composition characteristics and assess occupational health risks and odor pollution of volatile organic compounds (VOCs) from industrial activities in the Yangtze River Delta (YRD) region, China, one-year field measurements of VOCs were conducted simultaneously at an iron and steel industrial park (ISP), one chemical industrial park (CMP) and one petrochemical industrial park (PCP) from September, 2018 to August, 2019. The concentrations of VOCs were 80.2 ± 67.9 ppbv, 28.1 ± 27.2 ppbv and 144 ± 378 ppbv for ISP, CMP and PCP, respectively. Aromatics, alkanes and alkenes were the major components of VOCs at ISP, CMP and PCP, respectively. Moreover, the toluene to benzene ratios were 0.330 ± 0.302, 4.31 ± 6.48 and 1.84 ± 3.34, which generally showed the characteristics of combustion source for ISP, industrial activities for CMP and petrochemical industry for PCP, respectively. The hazard index values were 0.752 ± 0.438, 0.108 ± 0.248 and 0.090 ± 0.260 at ISP, CMP and PCP, which were generally lower than threshold limit value, suggesting a low noncarcinogenic risk for workers. Meanwhile, the 95th percentile LCR values of VOCs were 8.76 × 10-5, 1.15 × 10-5 and 1.00 × 10-5 at ISP, CMP and PCP, respectively, which were also under acceptable risk level, indicating a low carcinogenic risk. Benzene and 1,3-butadiene were main harmful substances for both noncarcinogenic and carcinogenic risks of VOCs. The odor levels of VOCs were 2.12 ± 4.21, 12.5 ± 28.7 and 1.01 ± 7.84 at ISP, CMP and PCP, respectively. Aromatics for ISP and sulfide compounds for CMP and PCP were primary pollutants for odor pollution. This work could improve the understanding of risk levels and odor characteristics of VOCs and benefit policy development on alleviating odor complaints and health risks for workers in YRD region, China.

Porous Core/Dense Shell PLA Microspheres Embedded with High Drug Loading of Bupivacaine Crystals for Injectable Prolonged Release.

Objective of the study was to design an injectable microsphere preparation with high drug loading of bupivacaine for prolonged release and local anesthetic. PLA or PLGA was used as the biodegradable matrix material to fabricate microspheres with the o/w emulsification-solvent evaporation method. The characterization of bupivacaine microspheres was observed by SEM, DSC, and XRPD. The microsphere preparation and extended drug release, as well as the plasma drug concentration and sciatic nerve blockade after injection of the microsphere formulation to rats were investigated. High drug-loading microspheres of more than 70% were successfully obtained with extended drug release over 5 days in vitro depending on the type of matrix and the feed ratio of drug to polymer. SEM, DSC, and XRPD results verified a novel microsphere structure characterized as the porous core composed of PLA material and form II bupivacaine crystals and dense shell formed of PLA layer. The mechanism that bupivacaine was dissolved inside the microsphere and diffused across the dense shell was suggested for drug release in vitro. The optimized PLA microsphere formulation showed low and steady plasma drug concentration over 5 days and prolonged duration of sensory and motor blockade of sciatic nerve lasted more than 3 days. Results indicated that the porous core-shell structure of PLA microsphere formulation would provide enormous potential as an injectable depot for locally prolonged delivery of bupivacaine and control of postoperative pain.