Objective: To evaluate the clinical efficacy and stability of a centric relation (CR)-guided approach combined with micro-implant anchorage and long traction hooks for root-controlled retraction of the maxillary anterior teeth in a patient with skeletal maxillary protrusion and dual bite, and to provide a reference for clinical practice. Methods: A case of a 29-year-old female patient with skeletal maxillary protrusion and an asymptomatic discrepancy between the maximum intercuspation position (MIP) and CR (dual bite) was reported. First, the CR was identified and obtained by cone beam computed tomography examination and clinical techniques, then was stabilized by glass ionomer bite registration and myofunctional training. Maintaining the CR, the maxillary micro-implants combined with long traction hooks were used to correct skeletal maxillary protrusion by facilitating maxillary anterior teeth retraction, and finally a new intercuspal occlusion was established to maintain long-term stability. A literature review was conducted to contextualize the treatment rationale and key steps. Results: Post-treatment, a coordinated and stable functional occlusion was established in CR without temporomandibular joint symptoms, and the condylar location was coordinated with the glenoid fossa. Controlled root retraction of the maxillary anterior segment and facial profile improvement were achieved. At 3-year follow-up, both occlusion in the CR and condylar positions remained stable. The literature review indicated that, in patients with CR-MIP discrepancy, prioritizing the identification and stabilization of CR is critical, and micro-implant anchorage with long traction hooks effectively facilitates maxillary anterior teeth retraction and profile improvement. Conclusion For skeletal maxillary protrusion with dual bite, a CR-first strategy combined with micro-implant anchorage and long-hook mechanics for root-controlled anterior retraction can concurrently improve stomatognathic function and facial aesthetics, demonstrating favorable mid- to long-term stability.

Objective Exploring the position and bone wall thickness characteristics of the maxillary central inci-sors in Southern Chinese adults to provide a clinical reference for the design of immediate maxillary central incisor im-plantation surgery.Methods The hospital ethics committee approved the study,and the patients provided informed consent.CBCT images of 990 adult patients(aged 20-79 years)from the Stomatology Hospital(January 2018 to Decem-ber 2021)were categorized based on the dental arch form and age-sex groups.Sagittal CBCT images of the maxillary central incisors were used to measure the labial and palatal bone thickness wall at 4 mm the CEJ to apical,the middle of the root,and the angle between the tooth long axis and the long axis of the alveolar process,to compare the thickness of the labial and palatal bone walls in samples of male and female patients,and to explore the relationship between the angle between the tooth long axis and the alveolar process long axis in samples of male and female patients in different age groups(20-39 years;40-59 years;60-79 years).Results Significant differences were found in the labiopalatine side of the alveolar bone of the maxillary incisor root position.A total of 95.8％(948/990)of the maxillary incisors were positioned more buccally,4.1％(41/990)were positioned more midway,and 0.1％(1/990)were positioned more palatal-ly.The thicknesses of the bone wall at the CEJ of 4 mm below the palatal side,the middle of the root,and at the apex were greater(1.82±0.56 mm,3.20±1.10 mm,and 7.70±2.00 mm,respectively)than those at the labial side(1.21± 0.32 mm,0.89±0.35 mm,and 1.86±0.82 mm,respectively),with statistical significance(P＜0.05).Male bone wall thickness was generally greater than female bone wall thickness(P＜0.05).The angle between the long axis of male teeth and the alveolar bone was 14.77°±5.66°,while that of female teeth was 12.80°±5.70°,with a statistically signifi-cant difference(P＜0.05).The angle between the long axis of teeth and the alveolar bone in the 40-59-year-old group and the 60-79-year-old group was greater than that in the 20-39-year-old group,and the difference was statistically sig-nificant(P＜0.05).Conclusion A total of 95.8％of adults in South China have maxillary central incisors with root de-viation toward the labial bone cortex.The thickness of the labial bone wall is much thinner than that of the labial bone wall,which is the middle of the thickness of the root.In Southern Chinese adults,the angle between the upper central incisor and the long axis of the alveolar bone in males is greater than that in females,and the degree of the angle in-creases with age.It is recommended to pay attention to the thickness of the bone wall around the root and the angle be-tween the teeth before immediate implantation surgery to choose a reasonable implantation plan.

Objective To analyze the spatial relationship between the roots of maxillary anterior premolars and the maxillary sinus,thus providing an anatomical basis for timing,planning,surgical approaches,and implant selection at this site.Methods Cone beam CT(CBCT)images were collected from 264 patients(aged 20-65 years)who visited the Ruihua Dental Clinic between January 2017 and March 2023.The minimum distance from the apex of the maxillary an-terior premolar roots to the lower wall of the maxillary sinus was measured on the coronal plane.The classification of the vertical relationship between the tooth root and the lower wall of the maxillary sinus was performed,and comparisons were made bilaterally,between genders,and among different age groups.Results The minimum distance(Q50)from the apex of the first maxillary premolar root to the lower wall of the maxillary sinus was 7.34 mm for the single-root type,7.80 mm for the buccal root of the double-root type,and 7.36 mm for the palatal root.For the second maxillary premo-lar,the median distance was 2.56 mm for the single root type,1.73 mm for the buccal root type,and 1.23 mm for the palatal root type.There was a significant difference in the shortest distance from the apex of the right second maxillary premolar single root to the lower wall of the maxillary sinus among the different age groups(P＜0.05),with the 20-29-year-old group having the smallest median distance(1.52 mm)and the≥40-year-old group having the largest(4.44 mm).There was no significant difference in the effect of sex or laterality on distance(P＞0.05).The most common vertical relationship between the apex of the maxillary anterior premolar roots and the lower wall of the maxillary sinus was non-contact.There was no significant difference in the vertical relationship classification between the single-root and dou-ble-root types(P＞0.05).Conclusion Most maxillary first premolar roots can provide sufficient bone height,which makes it easy to achieve immediate implantation.The maxillary second premolar root frequently involves insufficient bone,which is necessary to make full use of the bone wall of the extraction socket or the sinus floor cortical bone to achieve initial stability.The vertical relationship between the premolar root and maxillary sinus was influenced by age and dental position.Younger age groups often exhibit inadequate bone height,and the indication for immediate implan-tation should be carefully considered.The number of roots does not significantly affect the relationship between the sinus and root;however,double-rooted premolars offer more support for immediate implantation and socket healing due to the small root diameter and bony separation between the roots.

Objectives: . Branchio-oto syndrome (BOS) primarily manifests as hearing loss, preauricular pits, and branchial defects. EYA1 is the most common pathogenic gene, and splicing mutations account for a substantial proportion of cases. However, few studies have addressed the structural changes in the protein caused by splicing mutations and potential pathogenic factors, and several studies have shown that middle-ear surgery has limited effectiveness in improving hearing in these patients. BOS has also been relatively infrequently reported in the Chinese population. This study explored the genetic etiology in the family of a proband with BOS and provided clinical treatment to improve the patient’s hearing. Methods: . We collected detailed clinical features and peripheral blood samples from the patients and unaffected individuals within the family. Pathogenic mutations were identified by whole-exome sequencing and cosegregation analysis and classified according to the American College of Medical Genetics and Genomics guidelines. Alternative splicing was verified through a minigene assay. The predicted three-dimensional protein structure and biochemical experiments were used to investigate the pathogenicity of the mutation. The proband underwent middle-ear surgery and was followed up at 1 month and 6 months postoperatively to monitor auditory improvement. Results: . A novel heterozygous EYA1 splicing variant (c.1050+4 A>C) was identified and classified as pathogenic (PVS1(RNA), PM2, PP1). Skipping of exon 11 of the EYA1 pre-mRNA was confirmed using a minigene assay. This mutation may impair EYA1-SIX1 interactions, as shown by an immunoprecipitation assay. The EYA1-Mut protein exhibited cellular mislocalization and decreased protein expression in cytological experiments. Middle-ear surgery significantly improved hearing loss caused by bone-conduction abnormalities in the proband. Conclusion . We reported a novel splicing variant of EYA1 in a Chinese family with BOS and revealed the potential molecular pathogenic mechanism. The significant hearing improvement observed in the proband after middle-ear surgery provides a reference for auditory rehabilitation in similar patients.

External apical root resorption is among the most common risks of orthodontic treatment, and it cannot be completely avoided and predicted. Risk factors causing orthodontic root resorption can generally be divided into patient- and treatment-related factors. Root resorption that occurs during orthodontic treatment is usually detected by radiographical examination. Mild or moderate root absorption usually does no obvious harm, but close attention is required. When severe root resorption occurs, it is generally recommended to suspend the treatment for 3 months for the cementum to be restored. To unify the risk factors of orthodontic root resorption and its clinical suggestions, we summarized the theoretical knowledge and clinical experience of more than 20 authoritative experts in orthodontics and related fields in China. After discussion and summarization, this consensus was made to provide reference for orthodontic clinical practice.
Humans ; Tooth Movement Techniques/adverse effects* ; Root Resorption/etiology* ; Consensus ; Dental Cementum ; Risk Factors

To detect 20 common deafness gene mutations in non- syndromic deafness patients in China using PCR- RDB, and analyze and summarize the mutation data to explore the clinical value of this method. The PCR- RDB and Sanger sequencing were used to detect 20 common mutations of four deafness genes（, and ） in 500 patients with non- syndromic hearing loss . The Sanger sequencing was used to compare the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the deafness mutation detected by PCR- RDB. A total of 500 samples were detected. 147 wild- type samples, 81 homozygous mutant samples, 240 heterozygous mutant samples, 32 composite heterozygous mutant samples were detected using the PCR- RDB within the range of 20 gene mutations, which were identical to the Sanger sequencing results. GJB2 c.235delC and SLC26A4 c.919- 2 A>G are the most common hotspot mutations in this study, followed by mtDNA m. 1555 A>G. Compared with the Sanger sequencing method, the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the real- time fluorescence PCR melting curve method were 100%, and the Kappa value was one. PCR reverse dot-blot hybridization is a simple, rapid, sensitive and specific method for detecting 20 mutations of 4 common deafness genes in Chinese population, it is expected to be used in clinical detection of deafness genes in the future.

Objective: To detect 20 common deafness gene mutations in non- syndromic deafness patients in China using PCR- RDB, and analyze and summarize the mutation data to explore the clinical value of this method. Method: The PCR- RDB and Sanger sequencing were used to detect 20 common mutations of four deafness genes（GJB2, GJB3, SLC26A4 and mtDNA） in 500 patients with non- syndromic hearing loss . The Sanger sequencing was used to compare the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the deafness mutation detected by PCR- RDB. Result: A total of 500 samples were detected. 147 wild- type samples, 81 homozygous mutant samples, 240 heterozygous mutant samples, 32 composite heterozygous mutant samples were detected using the PCR- RDB within the range of 20 gene mutations, which were identical to the Sanger sequencing results. GJB2 c.235delC and SLC26A4 c.919- 2 A>G are the most common hotspot mutations in this study, followed by mtDNA m. 1555 A>G. Compared with the Sanger sequencing method, the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the real- time fluorescence PCR melting curve method were 100%, and the Kappa value was one. Conclusion PCR reverse dot-blot hybridization is a simple, rapid, sensitive and specific method for detecting 20 mutations of 4 common deafness genes in Chinese population, it is expected to be used in clinical detection of deafness genes in the future.

Objective: To detect 20 common deafness gene mutations in non-syndromic hearing loss patients in China using the melting curve method, and analyze and summarize the mutation data to explore the clinical value of this method. Methods: The real-time fluorescence PCR melting curve method was used to detect 20 common mutations of four deafness genes(GJB2,GJB3,SLC26A4 and mtDNA) in 492 patients with non-syndromic hearing loss recruited between March 2014 and September 2016 from the Otolaryngology Department of Xiangya Hospital, Central South University(283 males and 209 females, the age ranged from 1 to 48 years old). The Sanger sequencing method was used to compare the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the deafness mutation detected by the real-time fluorescence PCR melting curve method. Results: A total of 492 samples were detected. 193 wild-type samples, 93 homozygous mutant samples, 145 heterozygous mutant samples, 59 composite heterozygous mutant samples and 2 samples with unknown mutations were detected using the real-time fluorescence PCR melting curve method within the range of 20 gene mutations, whichwere identical to the Sanger sequencing results.The two samples were detected as unknown mutations by the real-time fluorescent PCR melting curve method were confirmed by Sanger sequencing, including a composite heterozygous mutant sample and a homogenous mutation sample. GJB2 c.235delC and SLC26A4 c.919-2 A>G were the most common hotspot mutations in this study, followed by mtDNA m.1555 A>G. Compared with the Sanger sequencing method, the sensitivity, specificity, positive predictive value, negative predictive value, and total coincidence rate of the real-time fluorescence PCR melting curve method were 100%, the Youden′s index was 1.0, and the Kappa value was 1. Conclusions The real-time fluorescence PCR melting curve method is suitable for the detection of deafness gene mutations. It has the advantages in terms of simple, rapid, high sensitivity and strong specificity and can accurately detect the 20 gene mutations of 4 common deafness genes in Chinese population, which is expected to be used for the clinical detection of deafness genes in the future.

Objective:To investigate the mechanism for the synergistic effect of interferon regulatory factor 4 (IRF4) and microphthalmia-associated transcription factor (MITF) on tyrosinase (TYR)promoter.Methods:The synergistic transcriptional effect,subcellular localization,and protein-protein interaction for IRF4 and MITF were observed by luciferase assay,immunofluorescence,GST-pull down,and co-immunoprecipitation,respectively.Results:IRF4 and MITF proteins were co-expressed in the cell nucleus.IRF4 augmented the transcriptional function of MITF (but not the mutant MITF) to activate the expression of the TYR promoter,but with no effect on other MITF-specific target promoters.IRF4 alone did not affect TYR promoter significantly.No direct interaction between the two proteins was noted.Conclusion:IRF4 and MITF exert a specifically synergistic effect on activation of TYR promoter through IRF4-mediated upregulation of transcriptional function of MITF.This synergistic effect is mainly regulated by MITF;DNA might be involved in the interaction between the two proteins.

OBJECTIVETo explore the pathogenetic mechanism of a family affected with Waardenburg syndrome.

METHODSClinical data of the family was collected. Potential mutation of the MITF, SOX10 and SNAI2 genes were screened. Plasmids for wild type (WT) and mutant MITF proteins were constructed to determine their exogenous expression and subcellular distribution by Western blotting and immunofluorescence assay, respectively.

RESULTSA heterozygous c.763C>T (p.R255X) mutation was detected in exon 8 of the MITF gene in the proband and all other patients from the family. No pathological mutation of the SOX10 and SNAI2 genes was detected. The DNA sequences of plasmids of MITFand mutant MITFwere confirmed. Both proteins were detected with the expected size. WT MITF protein only localized in the nucleus, whereas R255X protein showed aberrant localization in the nucleus as well as the cytoplasm.

CONCLUSIONThe c.763C>T mutation of the MITF gene probably underlies the disease in this family. The mutation can affect the subcellular distribution of MITF proteins in vitro, which may shed light on the molecular mechanism of Waardenburg syndrome caused by mutations of the MITF gene.

Adolescent ; Adult ; Case-Control Studies ; Child ; Child, Preschool ; Female ; Humans ; Male ; Middle Aged ; Mutation ; genetics ; Pedigree ; Waardenburg Syndrome ; genetics ; Young Adult