The human epidermal growth factor receptor 2 (HER2) is a major therapeutic target in cancer. While the oncogenic effects of HER2 hyperactivation are well characterized, the biological consequences of its deficiency remain poorly defined. Here, through exome sequencing analyses of a cohort of 720 families affected by isolated or syndromic orofacial clefts, we unexpectedly identified 5 distinct rare germline HER2 variants in 5 unrelated families with growth deficits, orofacial clefts, and other craniofacial, skeletal, and auditory anomalies. In Xenopus embryos, these variants failed to recapitulate the developmental effects of WT HER2. In cultured cells, they disrupted HER2 protein stability, membrane localization, or site-specific phosphorylation, resulting in diminished ERK signaling. Strikingly, knock-in mice expressing a patient-derived HER2 variant and mice maternally exposed to Tucatinib, a recently approved anti-HER2 drug, both replicated patient phenotypes: delayed growth and diverse craniofacial abnormalities, including ocular dysgenesis, short jaws, and cleft palate. Collectively, our findings define a developmental disorder that we designate GRACE syndrome (Growth Retardation and Craniofacial Malformations Caused by HER2 Deficiency), establish HER2’s essential role in human growth and craniofacial morphogenesis, and reveal that HER2-targeted therapies during pregnancy can induce craniofacial defects and lifelong growth impairment in fetuses.

Pain is a common issue for individuals undergoing orthodontic treatment, with some even discontinuing treatment due to the pain experienced. Furthermore, orthodontic pain is often accompanied by negative emotional responses such as anxiety and unease. This study aims to investigate the role of transient receptor potential vanilloid type 1 (TRPV1) in the mouse’s central nucleus of the amygdala (CeA), focusing on its involvement in nociception and anxiety during experimental orthodontic tooth movement (OTM). Twenty-five 8-week-old male C57BL/6J mice were randomly divided into five groups: blank, 0 centinewton (cN), 10 cN, 30 cN, and 50 cN, based on the force applied for OTM(n = 5). Behavioral responses were assessed at different time points. Face-rubbing behavior and Von Frey test were used as a measure of nociception during experimental OTM. Both Open Field (OF) and Elevated Plus Maze (EPM) tests were conducted to evaluate anxiety-related behaviors. Immunohistochemistry was used to study the localization of TRPV1 in the CeA(n = 5), while Western blotting was employed to measure its expression levels(n = 3). During the experimental OTM, all groups of mice exhibited nociception, with the 50 cN group showing the highest level of face rubbing and the minimum force value of von frey test on the first day (1 d). Mice subjected to different force values also showed different degrees of anxiety-related behavior. The anxiety-related indexes in the 30 cN group and 50 cN group were significantly higher than in the 0 cN group on the 28 d (P < 0.05). Immunofluorescence staining revealed that the TRPV1 expression in the 30 cN-1 d group was higher than in the 0 cN-1 d group (P < 0.001). Western blotting analysis showed that the TRPV1 expression in the CeA of the 30 cN group was significantly higher compared to the 0 cN-1 d group during experimental OTM, reaching its peak on the 1 d and 28 d time point (P < 0.001). The present study demonstrates that orthodontic procedures can induce pain and emotional changes, which may be associated with increased TRPV1 expression in the central amygdala. The study provides preliminary evidence that TRPV1 in CeA is involved in both nociception and anxiety behavior during orthodontic tooth movement.

Abstract Background This study aimed to investigate the biomechanics of maxillary dentition, specifically displacement patterns, midline deviation, and stress distribution of the first molar and anchorage teeth during first molar mesialization using clear aligners (CA) assisted by temporary anchorage devices (TADs) combined with different auxiliary attachments, including buccal buttons, aligner-based angel buttons and power arms. Methods Finite element models of the CA, micro-implants, maxillary teeth, periodontal ligament (PDL), and alveolar bone were constructed. Four finite element models were simulated: model A (CA alone, control); model B (CA with micro-implants connected to aligner-based angel buttons); model C (CA with micro-implants connected to buccal buttons on the first molar); and model D (CA with micro-implants connected to power arms on the buccal surface of the first molar). The simulations evaluated three-dimensional tooth displacement, midline deviation, tipping angles, and PDL hydrostatic pressure of the maxillary dentition. Results Mesialization of the first molar using CA alone resulted in mesiolingual tipping and intrusion, while anchorage teeth experienced distobuccal or distolingual tipping and extrusion. Midline deviation tended toward the edentulous side due to reciprocal forces. Auxiliary force systems generally improved the efficiency of molar mesial movement from 44.12% to 52.92% and reduced anchorage tooth displacement compared to the control. Aligner-based angel buttons showed the most effective anchorage stability and minimal midline deviation (0.0137 mm). Buccal buttons produced the largest mesial movement of the first molar, with pronounced tipping (0.714°) and uneven PDL stress. Power arms showed near-bodily movement of the first molar and relatively uniform PDL stress, although anchorage control was less pronounced than that of aligner-based angel buttons. Conclusion The combined use of micro-implants and auxiliary devices demonstrated distinct effects on the first molar mesialization and anchorage teeth stability. Notably, aligner-based angel buttons provided the most effective anchorage control and the least midline deviation, while power arms resulted in more bodily movement of the first molar.

This study constructed three-dimensional finite element (3D-FE) models of the upper airway and surrounding structures from spiral computed tomography (CT) data. An optimized fluid-structure interaction (FSI) analysis was applied to investigate the biomechanical effects of the mandibular advancement device (MAD) on peri-airway tissues, refining its therapeutic mechanism in obstructive sleep apnea (OSA). One adult patient diagnosed with moderate OSA underwent CT scans in natural sleep before and after 2 months of MAD therapy. 3D-FE models of the upper airway and surrounding structures were constructed from CT data to quantify morphological changes and displacements of the hyoid bone, soft palate, tongue, epiglottis, and the upper airway. FSI analysis was performed to assess airflow pressure and velocity in both the sagittal plane and cross-sections of the upper airway, as well as the displacement of the aforementioned soft tissues, at both peak inspiration and expiration. MAD-induced mandibular protrusion resulted in anterosuperior displacement of the tongue, soft palate, epiglottis, and hyoid bone, accompanied by shortening of the soft palate and lengthening of the epiglottis. These alterations dilated the upper airway in both sagittal and coronal dimensions, thereby increasing airway volume and minimum cross-sectional area. MAD also reduced and homogenized airflow pressure and velocity in both the sagittal plane and key cross-sections of the upper airway at peak inspiration and expiration, while attenuating the displacement of the pharyngeal wall, tongue, soft palate, and epiglottis, with effects more pronounced at peak inspiration. MAD treats OSA through a synergistic biomechanical mechanism. It enlarges the pharyngeal airway via anterosuperior repositioning of peri-airway tissues. This resultant upper airway dilation attenuates and homogenizes airflow pressure and velocity, thereby stabilizing the pharyngeal wall and peripharyngeal structures, with more pronounced effects during inspiration.

Aim or purpose: This study aims to elucidate the mechanisms underlying mesenchymal stem cells (MSCs)-mediated regulation of Treg/Th17 balance through extracellular vesicles (EVs)-modulated mitochondrial function, with the goal of identifying novel therapeutic targets to enhance MSC-driven bone remodeling and regeneration. Materials and methods: Fluorescent labeling combined with FC analysis was used to label and locate TFAM mRNA. WB was used to assess TFAM levels. mitochondrial DNA(mtDNA) copy number was quantified via qRT-PCR. ROS level was measured by DCFH-DA.A periodontal defect model was established in eighteen male SD rats. TFAM mRNA-PDLSCA and TFAM mRNA-OE-PDLSCA were transplanted into the defect sites. Bone mineral density and defect volume were evaluated via Micro-CT. ROS/ERK/HIF-1α level were quantified by WB. IHC staining was performed to assess the expression of Treg,Th17,IL-17,IL-10,TGF-β,RANKL,OPG,TRAP. Results: EVs mediated the intercellular transfer of TFAM mRNA.Following the translation of TFAM mRNA, the upregulated TFAM protein expression enhanced mtDNA copy number and reduced ROS production. The diminished ROS level attenuated ERK activation, thereby suppressed HIF-1α expression. HIF-1α shifted T cell metabolism from glycolysis to oxidative phosphorylation, ultimately promoted Treg differentiation and restored Treg/Th17 balance. Conclusions: Our findings suggest that MSCs-derived EVs transfer TFAM mRNA from MSCs to T cells. Following translation, the TFAM protein regulates T cell metabolic patterns by inhibiting the ROS-ERK-HIF-1α signaling pathway, thereby modulating the Treg/Th17 balance.

Cleft lip and/or palate (CL/P) is the most common craniofacial birth defect. Patients with CL/P typically exhibit severe malocclusions in the transverse, vertical, and sagittal directions, and often have poor oral hygiene. Due to the complex nature of the disease, the dental treatment for CL/P patients presents considerable challenges, sometimes resulting in interrupted treatments and subsequent treatment failures. Here, we present an interdisciplinary retreatment for an adolescent with unilateral complete cleft lip (UCCL), who initially received an orthodontic treatment elsewhere but faced issues such as poor oral hygiene, deep overbite of anterior teeth, significant discrepancies in the width of posterior teeth, and persistent spaces resulting from the alveolar cleft. Throughout the retreatment, we employed tooth remineralization accompanied by strict oral hygiene instructions, various skilled orthodontic techniques, surgical interventions, and aesthetic prosthodontic work. The adolescent showed dramatic improvements in facial and dental aesthetics, as well as in dental occlusion and function after treatment. In summary, this case report emphasizes the critical role of effective oral hygiene management and interdisciplinary teamwork among dental subspecialties in the treatment of CL/P patients.

Objectives To develop mini-screw templates using three-dimensional (3D) printing technology to prevent root damage during implantation, and to evaluate the accuracy and safety of the implantation process. Methods Thirteen patients requiring mini-screw implantation between the maxillary second premolar and first molar were recruited for this study. A total of 21 mini-screws were placed in vivo using patient-specific mini-screw templates designed with manipulation software. Following implantation, cone-beam computed tomography (CBCT) scans were obtained. The postoperative CBCT data were superimposed onto the preoperative scans using a correntropy-based registration algorithm to assess implant positioning. The accuracy and safety of mini-screw placement under the guidance of the 3D-printed templates were subsequently evaluated. Results The mean 3D deviation at the mini-screw tail was 1.10 ± 0.48 mm. The deviations in the coronal, sagittal, and vertical directions were 0.31 ± 0.28 mm, 0.38 ± 0.29 mm, and 0.88 ± 0.51 mm, respectively. The actual deviation (0.39 ± 0.30 mm) was significantly smaller than the permitted deviation (1.04 ± 0.45 mm), with the difference reaching statistical significance (P < 0.05). Conclusions The 3D-printed mini-screw templates demonstrated high accuracy and safety in guiding mini-screw implantation between the maxillary second premolar and first molar. The actual deviations observed were significantly smaller than the clinically accepted limits, indicating reliable positional control and minimized risk of root damage. Clinical significance 3D-printed templates significantly enhance the precision and predictability of orthodontic mini-screw placement and provide a clinically reliable technique.

Protrusive facial deformities, characterized by the forward displacement of the teeth and/or jaws beyond the normal range, affect a considerable portion of the population. The manifestations and morphological mechanisms of protrusive facial deformities are complex and diverse, requiring orthodontists to possess a high level of theoretical knowledge and practical experience in the relevant orthodontic field. To further optimize the correction of protrusive facial deformities, this consensus proposes that the morphological mechanisms and diagnosis of protrusive facial deformities should be analyzed and judged from multiple dimensions and factors to accurately formulate treatment plans. It emphasizes the use of orthodontic strategies, including jaw growth modification, tooth extraction or non-extraction for anterior teeth retraction, and maxillofacial vertical control. These strategies aim to reduce anterior teeth and lip protrusion, increase chin prominence, harmonize nasolabial and chin-lip relationships, and improve the facial profile of patients with protrusive facial deformities. For severe skeletal protrusive facial deformities, orthodontic-orthognathic combined treatment may be suggested. This consensus summarizes the theoretical knowledge and clinical experience of numerous renowned oral experts nationwide, offering reference strategies for the correction of protrusive facial deformities.

Introduction: This study analyzes the interdisciplinary management of a 17-year-old skeletal Class III patient with cleft lip and palate. The treatment involved orthodontic preparation followed by orthognathic surgery. Extraction of undersized teeth #12 and #22, along with strategic utilization of the #12 space for segmental maxillary arch narrowing, effectively reduced treatment duration while achieving optimal occlusal and facial outcomes. Case description: A 17-year-old male presented with concave profile, Angle Class III malocclusion, anterior crossbite, and maxillary midline deviation. Clinical evaluation revealed maxillary crowding (5mm), microdontia (#12, #22), and lingually inclined incisors (U1-NA=18.7°, L1-NB=14.8°). Cephalometric analysis confirmed skeletal Class III (ANB=-4.4°) and normodivergent growth pattern (GoGn-SN=31.8°). Treatment included extraction of #12 and #22, reshaping #13 to replace #12, and surgical maxillary constriction using the residual 3mm space at #12 region. Total treatment duration was 21 months. Discussion: Pre-surgical coordination of maxillary and mandibular widths is critical. The existing #12 space facilitated direct surgical reduction of maxillary width, eliminating prolonged orthodontic space closure and arch coordination. This approach optimized treatment efficiency while ensuring stable occlusal outcomes. Conclusion/clinical significance: Strategic integration of orthodontic preparation and surgical maxillary width adjustment can significantly reduce overall treatment duration in cleft-associated skeletal discrepancies. This case demonstrates the clinical efficacy of interdisciplinary planning for complex dentofacial deformities.

Nonsyndromic orofacial clefts (NSOFCs) are the most common human craniofacial defects. Genetic factors play a critical role in the pathogenesis of NSOFCs. However, known causal genes only explain a minority of the estimated heritability. To unveil the underlying genetic architecture, exome sequencing is performed on 214 sporadic patients with NSOFCs. The findings substantiate the genetic and allelic heterogeneity of NSOFCs and underscore the crucial role of dysregulation of OFC-related signaling pathways in the occurrence of NSOFCs. Besides, the candidate variants discovered provide a fruitful resource for further genetic studies. Particularly, three BOC missense variants (p.R407W, p.G436S, and p.D1018N) are identified in three unrelated cases with cleft palate. In parallel, a BOC nonsense variant (p.R681X), co-segregating with a GLI2 missense variant (p.A543G), is identified in a multiplex family with microform cleft lip. Functional studies demonstrate while the four BOC variants are hypomorphic alleles, the GLI2 variant is a hypermorphic allele. The counteraction between BOC p.R681X allele and GLI2 p.A543G allele accounts for the mild phenotype in the multiplex family. Thus, this study establishes BOC as a novel causal gene and implicates a two-locus model of inheritance via the epistatic antagonism of two SHH pathway variants in NSOFCs.

Objective: Oral squamous cell carcinoma remains difficult to treat because of its marked tumor heterogeneity, highlighting the need to identify molecular subtypes with distinct therapeutic vulnerabilities. This study aimed to comprehensively characterize OSCC molecular subtypes and identify potential therapeutic targets. Materials and methods: We conducted an integrated analysis combining single-cell and bulk RNA sequencing from 709 OSCC cases. Protein interactions were examined using mass spectrometry and immunoprecipitation assays. The functional roles of key regulators were evaluated through in vitro cell proliferation and invasion assays, RNA sequencing of knockdown cell lines, and in vivo xenograft models. Statistical analyses included differential gene expression analysis, pathway enrichment, and IC50 determination for drug sensitivity. Results: We identified a distinct molecular OSCC subtype marked by concurrent activation of the mTORC1 and NF-κB pathways, with TTK emerging as a central regulator of this co-activation. Patients in this subtype exhibited pronounced genomic instability, reflected by increased tumor mutational burden, higher TP53 mutation frequency, copy number amplifications across multiple genomic regions. Mechanistically, mass spectrometry and co-immunoprecipitation assays showed that TTK directly interacts with the TAK1–TAB protein complex, thereby activating the NF-κB pathway. RNA sequencing of TTK knockdown cell lines demonstrated significant downregulation of both mTOR and NF-κB signaling upon TTK suppression. Functional assays confirmed that TTK inhibition strongly reduced OSCC cell proliferation and invasion and markedly enhanced cisplatin sensitivity in vitro and in vivo. Conclusion: Our findings establish TTK as a pivotal mediator defining a high-risk OSCC molecular subtype characterized by simultaneous activation of the mTORC1 and NF-κB pathways and severe genomic instability. The discovery of a direct interaction between TTK and the TAK1–TAB complex provides novel mechanistic insight into NF-κB activation, while its inhibition significantly improves cisplatin sensitivity. These results warrant further clinical evaluation of TTK inhibitors as a promising therapeutic strategy to improve outcomes in aggressive OSCC.

Cleft lip and palate is a common congenital developmental defect, which is mainly manifested as congenital oral and maxillofacial malformations. In patients with cleft lip and palate, jaw deformity often involves three-dimensional orientation, among which the correction of sagittal dysmorphism is the key point and difficulty in its diagnosis and treatment. In this article, we will elaborate on the indications and corrective methods for the treatment of maxillary retraction of cleft lip and palate, and introduce our experience in the sequential treatment of cleft lip and palate maxillary retraction in order to promote the standardization of its diagnosis and treatment.

Orofacial clefts (OFCs) represent the most prevalent congenital craniofacial anomalies, significantly impacting patients' appearance, oral function, and psychological well-being. Among these, non-syndromic OFCs (NSOFCs) are the most predominant type, with the etiology attributed to a combination of genetic and environmental factors. Rare variants of key genes involved in craniofacial development-related signaling pathway are crucial in the occurrence of NSOFCs, and our recent studies have identified PTCH1, a receptor-coding gene in the Hedgehog signaling pathway, as a causative gene for NSOFCs. However, the role of PTCH2, the paralog of PTCH1, in pathogenesis of NSOFCs remains unclear. Here, we perform whole-exome sequencing to explore the genetic basis of 144 sporadic NSOFC patients. We identify five heterozygous variants of PTCH2 in four patients: p.L104P, p.A131G, p.R557H, p.I927S, and p.V978D, with the latter two co-occurring in a single patient. These variants, all proven to be rare through multiple genomic databases, with p.I927S and p.V978D being novel variants and previously unreported. Sequence alignment suggests that these affected amino acids are evolutionarily conserved across vertebrates. Utilizing predictive structural modeling tools such as AlphaFold and SWISS-MODEL, we propose that these variants may disrupt the protein's structure and function. In summary, our findings suggest that PTCH2 may be a novel candidate gene predicted to be associated with NSOFCs, thereby broadening the spectrum of causative genes implicated in the craniofacial anomalies.

Multiple supernumerary teeth, combined with numerous impacted teeth, can lead to various malocclusions, posing significant treatment challenges. While certain genes associated with syndromic cases of multiple supernumerary and impacted teeth have been identified, the etiologies of non-syndromic cases still largely remain elusive. Here, we report a treatment of a 12-year-old boy who presented with 10 supernumerary teeth and 6 impacted teeth, accompanied by a genetic analysis to explore the underlying etiology. During the treatment, fifteen teeth were extracted, and various skilled techniques, including the closed-eruption technique and the application of by-pass arches, were utilized. Post-treatment, traction was successful for all the impacted teeth, without any tooth mobility or reduction in gingival height. Space closure, well-aligned teeth, and excellent functional occlusion were achieved. Furthermore, comprehensive genetic analysis was conducted through whole-exome sequencing on the patient and his parents, which revealed a potential link between the patient’s numerous supernumerary teeth and abnormal mineralization. Notably, the p.Ser496Pro variant in the TCF7L2 gene was identified as a potential candidate variant in this patient. Overall, our findings not only report the treatment of a rare case involving multiple supernumerary and impacted teeth but also offer valuable insights into the molecular basis of supernumerary teeth.

Cleft lip and palate (CLP) is one of the most common birth defects worldwide. It typically results in significant maxillary dysplasia, causing severe oral function problems and substantially affecting the patient’s facial aesthetics. Maxillary anterior segmental distraction osteogenesis (MASDO) has gained popularity in recent years as an effective treatment for correcting maxillary dysplasia. However, the evaluation of its effectiveness in patients with CLP varies across different studies. Our research was aimed at providing evidence of the effects of MASDO among CLP patients. A meta-analysis covered Medline, Web of Science, Embase, Scopus, and Cochrane Library. Controlled clinical trial studies published before February 2024 and analyzed changes in maxillary cephalometric landmarks before and after MASDO among patients with maxillary hypoplasia and CLP were included. Our meta-analysis included 10 papers in total. One study was at low risk of bias, seven were at medium risk, and two were at serious risk. MASDO significantly increased the maxillary length. The mean SNA angle increased by 6.43° (95

Orofacial clefts (OFCs) are the most common congenital craniofacial disorders and cause serious problems with the appearance, orofacial function and mental health of the patients. The fibroblast growth factor (FGF) signaling pathway is critical for several aspects of craniofacial development and loss-of-function mutations of coding genes for multiple FGFs and FGFRs can lead to OFCs. We recently characterized FAM3B as a novel ligand of FGF signaling, which, through binding to FGFRs and activating downstream ERK, regulates craniofacial development in Xenopus. In this study, we identify two rare variants in FAM3B (p.Q61R and p.D128G) via target region sequencing of FAM3B on 144 unrelated sporadic patients with non-syndromic OFCs (NSOFCs). Bioinformatic analysis predict that these two variants are likely to be damaging and biochemical experiments show that these two variants weaken the FGF ligand activity of FAM3B by decreasing its expression and thus secretion. In summary, our results indicate that FAM3B is a novel candidate gene for NSOFCs in humans.

OBJECTIVES:Unilateral complete cleft lip and palate (UCCLP) is one of the most severe clinical subtypes among cleft lip and palate (CLP), making repair surgery and subsequent orthodontic treatment particularly challenging. Presurgical nasoalveolar molding (PNAM) has shown conflicting and heterogeneous results in the treatment of UCCLP patients, raising questions about whether the diversity in alveolar anatomical morphology among these patients plays a role in the effectiveness of PNAM treatment.MATERIALS AND METHODS:We collected 90 digital maxillary models of infants with UCCLP and performed mathematical clustering analysis, including principal component analysis (PCA), decision tree modeling, and area under the ROC Curve (AUC) analysis, to classify alveolar morphology and identify key measurements. We also conducted clinical evaluations to assess the association between the alveolar morphology and CLP treatment outcomes.RESULTS:Using mathematical clustering analysis, we classified the alveolar morphology into three distinct types: average form, horizontal form, and longitudinal form. The decision tree model, AUC analysis, and comparison analysis revealed that four measurements (Trans ACG-ACL, ML length, MG length and Inc length) were essential for clustering the alveolar morphology of infants with UCCLP. Furthermore, the blinded clinical evaluation indicated that UCCLP patients with alveolar segments of horizontal form had the lowest treatment outcomes.CONCLUSION:Overall, our findings establish a novel quantitative classification system for the morphology of alveolar bone in infants with UCCLP and suggest that this classification may be associated with the outcomes of CLP treatment.CLINICAL RELEVANCE:The multidisciplinary CLP team should thoroughly evaluate and classify the specific alveolar morphology when administering PNAM to infants with UCCLP.