Endogenous glucose-driven cascade reaction of nano-drug delivery for boosting multidrug-resistant bacteria-infected diabetic wound healing.

Multidrug-resistant (MDR) bacteria-infected wound healing remains greatly challenging, especially in diabetic patients. Herein, a novel nano-drug delivery based on endogenous glucose-driven cascade reaction is proposed for boosting MDR bacteria-infected diabetic wound healing with high efficacy by improving wound microenvironment and enhancing photodynamic antibacterial activity. The composite nanoagent is first self-assembled by integrating berberine (BBR) and epigallocatechin gallate (EGCG) from natural plant extracts, named as BENPs, which is successively coated with manganese dioxide nanoshells (MnO2 NSs) and glucose oxidase (GOX) to form the final BEMGNPs. The cascade reaction is triggered by glucose at the wound site of diabetes which is specifically catalyzed by GOX in the BEMGNPs to produce gluconic acid and hydrogen peroxide (H2O2). That is subsequently to decompose MnO2 NSs in the BEMGNPs to generate oxygen (O2). The BEMGNPs as photosensitizers effectively produce reactive oxygen species (ROS) to enhance the eradication of bacteria with the assistance of O2. Under the synergistic function of the cascaded reaction, the BEMGNPs present excellent antibacterial efficacy even for MDR bacteria. The in vivo experiments explicitly validate that the constructed nano-drug delivery can augment the MDR bacteria-infected diabetic wound healing with excellent biosafety. The as-proposed strategy provides an instructive way to combat ever-threatening MDR bacteria, which particularly is beneficial for diabetic patients.

Mandibular cortical bone remodeling characteristics in patients with extraction: A cone-beam computed tomography study.

INTRODUCTION: This study evaluated the labial and lingual cortical bone remodeling characteristics of mandibular central incisors after retraction, which remain controversial among orthodontists. METHODS: Cortical bone remodeling and central incisor movement of 33 patients (aged 23.64 ± 4.30 years) who underwent mandibular first premolar extraction and incisor retraction at the crestal (S1), midroot (S2), and apical (S3) levels were analyzed using superimposed cone-beam computed tomography images on the basis of voxel-based registration of the mandibular stable region. Multivariate linear regression was used to explore the relationships between labial bone remodeling/tooth movement (BT) ratios and factors such as the ANB angle, mandibular plane angle (Mp-SN), and incisor movement patterns. The patients were divided into 4 groups according to the lingual cortical bone remodeling condition and the relationship between posttreatment incisor roots and the original lingual cortical bone border. At the 3 levels (S1, S2, and S3), the classifications of cortical bone remodeling of the mandibular incisors were calculated; t tests were used to compare the amount of labial and lingual bone remodeling, BT ratios, and lingual bone remodeling/root over the original border (BRo) ratios. RESULTS: The mean labial BT ratios at all 3 levels were close to 1. Multivariate linear regression indicated that the tooth movement pattern negatively correlated with the BT ratio at the S2 and S3 levels (P <0.05). Lingual bone apposition occurs when the root penetrates the original lingual cortical bone border in most patients. BRo ratios can more accurately reflect the inherent remodeling ability of the lingual cortical bone than BT ratios. The mean lingual BRo ratios were (1) S1 level: mandibular left central incisor (T31), 0.87 ± 0.25 and mandibular right incisor (T41), 0.86 ± 0.25; (2) S2 level: T31, 0.81 ± 0.12 and T41, 0.80 ± 0.22; and (3) S3 level: T31, 0.76 ± 0.20 and T41, 0.83 ± 0.26. There was no significant difference between labial BT ratios and lingual BRo ratios at the S2 and S3 levels. CONCLUSIONS: The amount of labial cortical bone resorption caused by mandibular incisor retraction showed varied relationships with the amount of tooth movement. Bodily retraction may decrease the labial BT ratios at the S2 and S3 levels. Active lingual cortical bone apposition occurred when the roots penetrated the original lingual border and exhibited strong remodeling ability.

Business culture impairs facial trustworthiness judgments.

Previous research has found that business culture has a detrimental impact on interpersonal trust. To understand whether this impact extends to rapid, automatic, bottom-up judgments of facial trustworthiness, we conducted 4 experiments involving 244 participants from economic and non-economic backgrounds. We presented participants with both trustworthy and untrustworthy faces and asked them to make judgments on trustworthiness. The results show that individuals who are engaged in studying economics, work in an economics-related occupation, or are exposed to an imagined business culture evaluate trustworthy faces to be less trustworthy. The findings shed light on why and how business culture affects the formation of interpersonal trust.

Small nucleolar RNA host gene 5 plays a role in orthodontic tooth movement by inhibiting osteoclast differentiation.

BACKGROUND AND OBJECTIVES: The alveolar bone remodelling promoted by reasonable mechanical force triggers orthodontic tooth movement (OTM). The generation of osteoclasts is essential in this process. However, the mechanism of mechanical force mediating osteoclast differentiation remains elusive. Small nucleolar RNA host gene 5 (SNHG5), which was reported to mediate the osteogenic differentiation of bone marrow mesenchymal stem cells in our previous study, was downregulated in human periodontal ligament cells (hPDLCs) under mechanical force. At the same time, the RANKL/OPG ratio increased. Based on this, we probed into the role of SNHG5 in osteoclast formation during OTM and the relevant mechanism. MATERIALS AND METHODS: SNHG5 and the RANKL/OPG ratio under different compressive forces were detected by western blotting (WB) and qRT-PCR. Impact of overexpression or knockdown of SNHG5 on osteoclast differentiation was detected by qRT-PCR, WB and transwell experiments. The combination of SNHG5 and C/EBPß was verified by RNA immunoprecipitation and RNA pull-down assays. The expression of SNHG5 and osteoclast markers in gingiva were analysed by qRT-PCR and the paraffin sections of periodontal tissues were used for histological analysis. RESULTS: Compressive force downregulated SNHG5 and upregulated the RANKL/OPG ratio in hPDLCs. Overexpression of SNHG5 inhibited RANKL's expression and osteoclast differentiation. SNHG5 combined with C/EBPß, a regulator of osteoclast. The expression of SNHG5 in periodontal tissue decreased during OTM. CONCLUSION: SNHG5 inhibited osteoclast differentiation during OTM, achieved by affecting RANKL secretion, which may provide a new idea to interfere with bone resorption during orthodontic treatment.

Comparison of temporomandibular joints in relation to ages and vertical facial types in skeletal class II female patients: a multiple-cross-sectional study.

BACKGROUND: The temporomandibular joint (TMJ) is closely related to the dynamic balance and stability of mandibular function and orthodontic treatment. Skeletal class II female patients are thought to be at high risk for TMJ disease. The relationship between the TMJ and craniofacial structures is still controversial. This study compared the morphology and position of the TMJ in skeletal class II adolescents and adults with various vertical facial types using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 117 skeletal class II patients were divided into three groups according to the FH-GoGn angle (hypodivergent, normodivergent and hyperdivergent), with 40 class I normodivergent patients serving as controls. Each group contained two age subgroups (adolescents: 11-14 years old, adults: 18-35 years old). The size (condylar length, height, long and short axis diameter, glenoid fossa width and depth) and shape (condylar neck inclination, condylar head angle and long axis angle, articular eminence inclination) of the condyle and fossa, joint space (anterior, superior, posterior, mesial and lateral), and position of the fossa (vertical, transverse, and anteroposterior distance) and condyle were measured and compared using CBCT. RESULTS: Class II hypodivergent patients exhibited the greatest condylar length, height, and long- and short-axis diameter; steepest articular eminence; deepest fossa depth; largest superior, mesial and lateral joint spaces; and highest fossa position in both age groups. The manifestations of class II hyperdivergent patients were mostly the opposite. In adults, except for the condylar long axis angle, the measurements of the condyle increased differently among skeletal patterns, while the measurements of the fossa decreased, as the joint spaces and fossa position remained approximately stable compared with those in adolescents. CONCLUSION: The vertical skeletal pattern, rather than the class II sagittal skeletal pattern, may be the main factor affecting the morphology and position of the TMJ. Attention should be given to the TMJ area in hyperdivergent patients with a relatively poor-fit condyle-fossa relationship. The changes in the TMJ with age were mainly morphological rather than positional and varied with skeletal pattern.

Micro-environment-triggered chemodynamic treatment for boosting bacteria elimination at low-temperature by synergistic effect of photothermal treatment and nanozyme catalysis.

An injectable hydrogel dressing, Zr/Fc-MOF@CuO2@FH, was constructed by combing acid-triggered chemodynamic treatment (CDT) with low-temperature photothermal treatment (LT-PTT) to effectively eliminate bacteria without harming the surrounding normal tissues. The Zr/Fc-MOF acts as both photothermal reagent and nanozyme to generate reactive oxygen species (ROS). The CuO2 nanolayer can be decomposed by the acidic microenvironment of the bacterial infection to release Cu2+ and H2O2, which not only induces Fenton-like reaction but also enhances the catalytic capability of the Zr/Fc-MOF. The generated heat augments ROS production, resulting in highly efficient bacterial elimination at low temperature. Precisely, injectable hydrogel dressing can match irregular wound sites, which shortens the distance of heat dissipation and ROS diffusion to bacteria, thus improving sterilization efficacy and decreasing non-specific systemic toxicity. Both in vitro and in vivo experiments validated the predominant sterilization efficiency of drug-resistant methicillin-resistant Staphylococcus aureus (MRSA) and kanamycin-resistant Escherichia coli (KREC), presenting great potential for application in clinical therapy.

The characteristics of the gut microbiota in patients with pulmonary tuberculosis: A systematic review.

Increasing evidence has indicated dysbiosis of the gut microbiota in patients with pulmonary tuberculosis (PTB). However, the change in the intestinal microbiota varies between different studies. This systematic review was conducted to investigate the characteristics of the gut microbiota in PTB patients. The MBASE, MEDLINE, Web of Science, and Cochrane Library electronic databases were systematically searched, and the quality of the retrieved studies was evaluated using the Newcastle-Ottawa scale. A total of 12 studies were finally included in the systematic review. Compared with healthy controls, the index reflecting α-diversity including the richness and/or diversity index decreased in 6 studies, while ß-diversity presented significant differences in PTB patients in 10 studies. Although the specific gut microbiota alterations were inconsistent, short-chain fatty acid-producing bacteria (including Lachnospiraceae, Ruminococcus, Blautia, Dorea, and Faecalibacterium), bacteria associated with an inflammatory state (e.g., Prevotellaceae and Prevotella), and beneficial bacteria (e.g., Bifidobacteriaceae and Bifidobacterium) were commonly noted. Our systematic review identifies key evidence for gut microbiota alterations in PTB patients, in comparison with healthy controls; however, no consistent conclusion could be drawn, due to the inconsistent results and heterogeneous methodologies of the enrolled studies. Therefore, more well-designed research with standard methodologies and large sample sizes is required.

Engineered Bacterial Biomimetic Vesicles Reprogram Tumor-Associated Macrophages and Remodel Tumor Microenvironment to Promote Innate and Adaptive Antitumor Immune Responses.

Tumor-associated macrophages (TAMs) are among the most abundant infiltrating leukocytes in the tumor microenvironment (TME). Reprogramming TAMs from protumor M2 to antitumor M1 phenotype is a promising strategy for remodeling the TME and promoting antitumor immunity; however, the development of an efficient strategy remains challenging. Here, a genetically modified bacterial biomimetic vesicle (BBV) with IFN-γ exposed on the surface in a nanoassembling membrane pore structure was constructed. The engineered IFN-γ BBV featured a nanoscale structure of protein and lipid vesicle, the existence of rich pattern-associated molecular patterns (PAMPs), and the costimulation of introduced IFN-γ molecules. In vitro, IFN-γ BBV reprogrammed M2 macrophages to M1, possibly through NF-κB and JAK-STAT signaling pathways, releasing nitric oxide (NO) and inflammatory cytokines IL-1ß, IL-6, and TNF-α and increasing the expression of IL-12 and iNOS. In tumor-bearing mice, IFN-γ BBV demonstrated a targeted enrichment in tumors and successfully reprogrammed TAMs into the M1 phenotype; notably, the response of antigen-specific cytotoxic T lymphocyte (CTL) in TME was promoted while the immunosuppressive myeloid-derived suppressor cell (MDSC) was suppressed. The tumor growth was found to be significantly inhibited in both a TC-1 tumor and a CT26 tumor. It was indicated that the antitumor effects of IFN-γ BBV were macrophage-dependent. Further, the modulation of TME by IFN-γ BBV produced synergistic effects against tumor growth and metastasis with an immune checkpoint inhibitor in an orthotopic 4T1 breast cancer model which was insensitive to anti-PD-1 mAb alone. In conclusion, IFN-γ-modified BBV demonstrated a strong capability of efficiently targeting tumor and tuning a cold tumor hot through reprogramming TAMs, providing a potent approach for tumor immunotherapy.

All-in-one porous membrane enables full protection in guided bone regeneration.

The sophisticated hierarchical structure that precisely combines contradictory mechanical and biological characteristics is ideal for biomaterials, but it is challenging to achieve. Herein, we engineer a spatiotemporally hierarchical guided bone regeneration (GBR) membrane by rational bilayer integration of densely porous N-halamine functionalized bacterial cellulose nanonetwork facing the gingiva and loosely porous chitosan-hydroxyapatite composite micronetwork facing the alveolar bone. Our GBR membrane asymmetrically combine stiffness and flexibility, ingrowth barrier and ingrowth guiding, as well as anti-bacteria and cell-activation. The dense layer has a mechanically matched space maintenance capacity toward gingiva, continuously blocks fibroblasts, and prevents bacterial invasion with multiple mechanisms including release-killing, contact-killing, anti-adhesion, and nanopore-blocking; the loose layer is ultra-soft to conformally cover bone surfaces and defect cavity edges, enables ingrowth of osteogenesis-associated cells, and creates a favorable osteogenic microenvironment. As a result, our all-in-one porous membrane possesses full protective abilities in GBR.

Novel Variants of CEP152 in a Case of Compound-Heterozygous Inheritance of Epilepsy.

Introduction CEP152 encodes protein Cep152, which associates with centrosome function. The lack of Cep152 can cause centrosome duplication to fail. CEP152 mutates, causing several diseases such as Seckel syndrome-5 and primary microencephaly-9. Methods In this study, we reported a patient diagnosed with epilepsy in Tianjin Children's Hospital. We performed clinical examination and laboratory test, and whole-exome sequencing was performed for the proband's and his parents' peripheral blood. The suspected compound-heterozygous variant in the CEP152 gene was verified by Sanger sequencing and quantitative real-time polymerase chain reaction technology. Results We discovered three variants-two of them from CEP152 and one from HPD . The result showed the variants in CEP152 only. The patient presented with seizures frequently. Sanger sequencing showed two novel variants in CEP152 are in exon26 (NM_014985.3 c.3968C > A p.Ser1323*) and in exon16 (NM_014985.3 c.2034_2036del p.Tyr678*). Conclusions We reported a novel compound-heterozygous variant in the CEP152 gene in this study. Most of the phenotypes are Seckel syndrome and primary microencephaly, and the novel variant may cause an atypical phenotype that is epilepsy.

Reusable and self-sterilization mask for real-time personal protection based on sunlight-driven photocatalytic reaction.

Personal protective masks play critical role in preventing the disease epidemic and resisting pathogenic bacterial infestation. However, large quantities of masks were disposed during COVID-19 epidemic, which caused environmental problem and huge economic burden. Herein, we developed reusable masks with inherent antimicrobial and self-cleaning features under solar irradiation. With spun-bonded nonwoven fabrics (SNF) layer as substrate, copper sulfide@polydopamine nanoparticles are deposited on SNF layer (CuS@PDANPs-SNF), which presents excellent photocatalytic activity. Under solar irradiation, CuS@PDANPs produce abundant of singly linear oxygen (1O2), which inactivates pathogenic bacteria with high efficiency over 99%. Interestingly, CuS@PDANPs-SNF cannot cause high temperature to bring any uncomfortable to the person, which is suitable for human to wear in daily life. Such design effectively protect person from the transmission of viral aerosol. Meanwhile, CuS@PDANPs-SNF masks are reusable and still maintain robust bactericidal ability after washing. The sunlight-mediated self-sterilization at low temperature endows CuS@PDANPs-SNF masks as powerful personal protective equipment for daily protection, which also provides an instructive way for reducing the environmental impact.

LncRNA ADAMTS9-AS2 regulates periodontal ligament cell migration under mechanical compression via ADAMTS9/fibronectin.

BACKGROUND: Periodontal ligament cells (PDLCs) are key mechanosensory cells involved in extracellular matrix (ECM) remodeling during orthodontic tooth movement (OTM). Mechanical force changes the ECM components, such as collagens and matrix metalloproteinases. However, the associations between the changes in ECM molecules and cellular dynamics during OTM remain largely uncharacterized. OBJECTIVES: To investigate the influence of mechanical force on the morphology and migration of PDLCs and explore the interaction between ECM remodeling and cellular dynamics, including the detailed mechanisms involved. METHODS: Human PDLCs (hPDLCs) were subjected to a static mechanical compression to mimic the compression state of OTM in vitro. A mouse OTM model was used to mimic the OTM procedure in vivo. The migration of hPDLCs was compared by wound healing and transwell migration assays. Moreover, expression levels of ADAM metallopeptidase with thrombospondin type 1 motif 9 (ADAMTS9) and fibronectin (FN) in hPDLCs were determined via western blotting, immunofluorescence staining, and enzyme-linked immunosorbent assays. Expression levels of ADAMTS9 and FN in mice were assessed via immunohistochemical staining. Additionally, the relative expression of long non-coding RNA (lncRNA) ADAMTS9-antisense RNA 2 (ADAMTS9-AS2) was assessed via quantitative real-time polymerase chain reaction. ADAMTS9-AS2 knockdown was performed to confirm its function in hPDLCs. RESULTS: Mechanical compression induced changes in the morphology of hPDLCs. It also promoted migration and simultaneous upregulation of FN and downregulation of ADAMTS9, a fibronectinase. The mouse OTM model showed the same expression patterns of the two proteins on the compression side of the periodontium of the moved teeth. RNA sequencing revealed that lncRNA ADAMTS9-AS2 expression was significantly upregulated in hPDLCs under mechanical compression. After knocking down ADAMTS9-AS2, hPDLCs migration was significantly inhibited. ADAMTS9 expression was increased as FN expression decreased compared to that in the control group. Moreover, knockdown of ADAMTS9-AS2 reduced the effect of mechanical compression on hPDLCs migration and reversed the expression change of ADAMTS9 and FN. RNA immunoprecipitation revealed direct binding between ADAMTS9-AS2 and ADAMTS9 protein. CONCLUSION: Our study suggests that mechanical compression induces the expression of ADAMTS9-AS2, which directly binds to ADAMTS9 and inhibits its function, leading to the promotion of downstream FN expression and ECM remodeling to facilitate hPDLCs migration and maintain the stability of the periodontium.

Graph embedding-based heterogeneous domain adaptation with domain-invariant feature learning and distributional order preserving.

Heterogeneous domain adaptation (HDA) methods leverage prior knowledge from the source domain to train models for the target domain and address the differences in their feature spaces. However, incorrect alignment of categories and distribution structure disruption may be caused by unlabeled target samples during the domain alignment process for most existing methods, resulting in negative transfer. Additionally, the previous works rarely focus on the robustness and interpretability of the model. To address these issues, we propose a novel Graph embedding-based Heterogeneous domain-Invariant feature learning and Distributional order preserving framework (GHID). Specifically, a bidirectional robust cross-domain alignment graph embedding structure is proposed to globally align two domains, which learns the domain-invariant and discriminative features simultaneously. In addition, the interpretability of the proposed graph structures is demonstrated through two theoretical analyses, which can elucidate the correlation between important samples from a global perspective in heterogeneous domain alignment scenarios. Then, a heterogeneous discriminative distributional order preserving graph embedding structure is designed to preserve the original distribution relationship of each domain to prevent negative transfer. Moreover, the dynamic centroid strategy is incorporated into the graph structures to improve the robustness of the model. Comprehensive experimental results on four benchmarks demonstrate that the proposed method outperforms other state-of-the-art approaches in effectiveness.

Glucose-metabolism-triggered colorimetric sensor array for point-of-care differentiation and antibiotic susceptibility testing of bacteria.

Simple and sensitive discrimination of multiple bacteria and antimicrobial susceptibility test (AST) are significant for food safety, clinical diagnosis and treatment. Herein, based on different metabolic ability of bacteria on glucose, we presented a colorimetric sensor array for point-of-care testing (POCT) of multiple bacteria with methyl red (MER), bromothymol blue (BTB) and bromocresol green (BCG) as probes. Different bacteria resulted in different color changes of three probes, which was converted to RGB (Red (R)/Green (G)/Blue (B)) signals by the color recognizer APP loaded on smartphone. The sensor array performed differentiation of eleven species of bacteria, achieving the quantitative analysis of individual bacteria in tap water and differentiation of bacterial mixtures. Interestingly, the sensor array can be used for AST and evaluating minimal inhibitory concentration (MIC) of antibiotics to bacteria. The research provided meaningful guidance for distinguishing multiple bacteria and evaluating MIC, presenting great potential in practical application.

Biomechanical analysis of miniscrew-assisted molar distalization with clear aligners: a three-dimensional finite element study.

BACKGROUND/OBJECTIVES: To compare the biomechanical characteristics of maxillary molar distalization with clear aligners in conjunction with three types of miniscrew anchorage. MATERIALS/METHODS: Three-dimensional (3D) finite element models of maxillary molar distalization with clear aligners and three types of miniscrew anchorage were established, including (A) control group, (B) direct buccal miniscrew anchorage group, (C) direct palatal miniscrew anchorage group, and (D) indirect buccal miniscrew anchorage group. The 3D displacement of maxillary teeth and the principal stress (maximum tensile and compressive stress) on the root and periodontal ligament (PDL) during molar distalization were recorded. RESULTS: The tooth displacement pattern during maxillary molar distalization in the four groups showed similarities, including labial tipping of anterior teeth, mesial and buccal tipping of premolars, and distal and buccal tipping of molars, but with varying magnitudes. Group C exhibited the greatest molar distalization, with the first molar achieving 0.1334 mm of crown distalization. Group D demonstrated a notable buccal crown movement (0.0682 mm) and intrusion (0.0316 mm) of the first premolar. Compared to Groups A and B, Groups C and D showed less labial crown tipping of the central incisor. Group B showed the greatest amount of maxillary incisor intrusion (central incisor: 0.0145 mm, lateral incisor: 0.0094 mm). Moreover, Groups C and D displayed significantly lower levels of compressive and tensile stress in the roots and PDL of the maxillary central and lateral incisors. LIMITATION: Molar distalization is a dynamic process involving sequential tooth movement stages; however, our research primarily examined the tooth movement patterns in the initial aligner. CONCLUSIONS/IMPLICATIONS: The use of miniscrew anchorage, especially direct palatal miniscrew anchorage, may enhance the treatment efficacy of maxillary molar distalization with clear aligners, leading to increased molar distalization, reduced mesial movement of premolars, and minimized labial tipping of anterior teeth.

A Zinc Oxide Nanowire-Modified Mineralized Collagen Scaffold Promotes Infectious Bone Regeneration.

Bone infection poses a major clinical challenge that can hinder patient recovery and exacerbate postoperative complications. This study has developed a bioactive composite scaffold through the co-assembly and intrafibrillar mineralization of collagen fibrils and zinc oxide (ZnO) nanowires (IMC/ZnO). The IMC/ZnO exhibits bone-like hierarchical structures and enhances capabilities for osteogenesis, antibacterial activity, and bacteria-infected bone healing. During co-cultivation with human bone marrow mesenchymal stem cells (BMMSCs), the IMC/ZnO improves BMMSC adhesion, proliferation, and osteogenic differentiation even under inflammatory conditions. Moreover, it suppresses the activity of Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans by releasing zinc ions within the acidic infectious microenvironment. In vivo, the IMC/ZnO enables near-complete healing of infected bone defects within the intricate oral bacterial milieu, which is attributed to IMC/ZnO orchestrating M2 macrophage polarization, and fostering an osteogenic and anti-inflammatory microenvironment. Overall, these findings demonstrate the promise of the bioactive scaffold IMC/ZnO for treating bacteria-infected bone defects.

Alveolar bone remodelling and stability of mandibular incisors in adult patients after orthodontic treatment with premolar extractions: A prospective follow-up study.

OBJECTIVE: To evaluate alveolar bone remodelling and stability of mandibular incisors in adult orthodontic extraction patients. MATERIALS AND METHODS: Cone-beam computed tomography images of 25 adult patients undergoing extraction were collected before orthodontic treatment (T1), after orthodontic treatment (T2), and after at least 1 year of retention (T3). The labial and lingual alveolar bone heights (ABH), thickness (ABT), and tooth movement of the mandibular incisors were measured during the retraction (T2-T1) and retention (T3-T2) periods. According to the tooth movement during the retention period, the mandibular incisors were further divided into stable and unstable groups, and the correlation between L1-BMe and stability was evaluated. RESULTS: The labial and lingual ABHs significantly increased after orthodontic treatment and decreased during the retention period. The lingual ABH was 7.36 ± 2.27 mm at T2 and 5.37 ± 1.98 mm at T3, indicating a great bone remodelling capacity. The labial ABT exhibited a significant increase during orthodontic treatment and a slight decrease during the retention period, while the lingual ABT showed an opposite trend. During the retention period, the root apex moved labially into the alveolar bone housing. L1-BMe significantly increased during orthodontic treatment and decreased during the retention period. Compared to the stable group, lingual ABH and L1-BMe at T2 was significantly higher, and lingual ABT was smaller in the unstable group. CONCLUSION: Post-treatment lingual alveolar bone defects of the mandibular incisors could recover to some extent during the retention period. There was a negative correlation between post-treatment L1-BMe and mandibular incisor stability.

Facial profile evaluation and prediction of skeletal class II patients during camouflage extraction treatment: a pilot study.

BACKGROUND: The evaluation of the facial profile of skeletal Class II patients with camouflage treatment is of great importance for patients and orthodontists. The aim of this study is to explore the key factors in evaluating the facial profile esthetics and to predict the posttreatment facial profile esthetics of skeletal Class II extraction patients. METHODS: 124 skeletal Class II extraction patients were included. The pretreatment and posttreatment cephalograms were analyzed by a trained expert orthodontist. The facial profile esthetics of pretreatment and posttreatment lateral photographs were evaluated by 10 expert orthodontists using the visual analog scale (VAS). The correlation between subjective facial profile esthetics and objective cephalometric measurements was assessed. Three machine-learning methods were used to predict posttreatment facial profile esthetics. RESULTS: The distances from lower and upper lip to the E plane and U1-APo showed the stronger correlation with profile esthetics. The changes in lower lip to the E plane and U1-APo during extraction exhibited the stronger correlation with changes in VAS score (r = - 0.551 and r = - 0.469). The random forest prediction model had the lowest mean absolute error and root mean square error, demonstrating a better prediction accuracy and fitting effect. In this model, pretreatment upper lip to E plane, pretreatment Pog-NB and the change of U1-GAll were the most important variables in predicting the posttreatment score of facial profile esthetics. CONCLUSIONS: The maxillary incisor protrusion and lower lip protrusion are key objective indicators for evaluating and predicting facial profile esthetics of skeletal Class II extraction patients. An artificial intelligence prediction model could be a new method for predicting the posttreatment esthetics of facial profiles.