OBJECTIVE: To analyze RELT gene mutation found in a pedigree with clinical features and inheritable pattern consistent with amelogenesis imperfecta (AI) in China, and to study the relationship between its genotype and phenotype. METHODS: Clinical and radiological features were recorded for the affected individuals. Peripheral venous blood samples of the patient and family members were collected for further study, and the genomic DNA was extracted to identify the pathogenic gene. Whole exome sequencing (WES) was performed to analyze the possible pathogenic genes, and Sanger sequencing was performed for validation. SIFT and PolyPhen-2 were used to predict and analyze the mutation effect. Comparison of RELT amino acids across different species were performed by using Uniprot website. In addition, the three-dimen-sional structures of the wild type and mutant proteins were predicted by Alphafold 2. RESULTS: The proband exhibited typical hypocalcified AI, with heavy wear, soft enamel, rough and discolored surface, and partial enamel loss, while his parents didn ' t have similar manifestations. WES and Sanger sequencing results indicated that the proband carries a homozygous frameshift mutation in RELT gene, NM_032871.3: c.1169_1170del, and both of his parents were carriers. This mutation was predicted to be pathogenic by SIFT and PolyPhen-2. Up to now, there were 11 mutation sites in RELT gene were reported to be associated with AI, and all of the patients exhibited with hypocalcified AI. Compared with the wild-type RELT protein, the mutant protein p. Pro390fs35 conformation terminated prematurely, affecting the normal function of the protein. CONCLUSION Through phenotype analysis, gene sequencing, and functional prediction of a Chinese family with typical amelogenesis imperfecta, this study found that RELT gene frameshift mutation can lead to protein dysfunction in AI patients. Further research will focus on the role and mechanism of RELT in enamel development at the molecular and animal levels, providing molecular biology evidence for the genetic counseling, prenatal diagnosis, and early prevention and treatment of AI.
Humans ; Amelogenesis Imperfecta/genetics* ; Frameshift Mutation ; Male ; Pedigree ; Female ; China ; Exome Sequencing ; Phenotype ; Adult

OBJECTIVES: We propose a YOLOv11-TDSP model for improving the accuracy of dental abnormality detection on panoramic oral X-ray images. METHODS: The SHSA single-head attention mechanism was integrated with C2PSA in the backbone layer to construct a new C2PSA_SHSA attention mechanism. The computational redundancy was reduced by applying single-head attention to some input channels to enhance the efficiency and detection accuracy of the model. A small object detection layer was then introduced into the head layer to correct the easily missed and false detections of small objects. Two rounds of structured pruning were implemented to reduce the number of model parameters, avoid overfitting, and improve the average precision. Before training, data augmentation techniques such as brightness enhancement and gamma contrast adjustment were employed to enhance the generalization ability of the model. RESULTS: The experiment results showed that the optimized YOLOv11-TDSP model achieved an accuracy of 94.5%, a recall rate of 92.3%, and an average precision of 95.8% for detecting dental abnormalities. Compared with the baseline model YOLOv11n, these metrics were improved by 6.9%, 7.4%, and 5.6%, respectively. The number of parameters and computational cost of the YOLOv11-TDSP model were only 12% and 13% of those of the high-precision YOLOv11x model, respectively. CONCLUSIONS The lightweight YOLOv11-TDSP model is capable of highly accurate identification of various dental diseases on panoramic oral X-ray images.
Radiography, Panoramic/methods* ; Humans ; Algorithms ; Tooth Abnormalities/diagnostic imaging*

Primary cilia function as critical sensory organelles that mediate multiple signaling pathways, including the Hedgehog (Hh) pathway, which is essential for organ patterning and morphogenesis. Disruptions in Hh signaling have been implicated in supernumerary tooth formation and molar fusion in mutant mice. Cilk1, a highly conserved serine/threonine-protein kinase localized within primary cilia, plays a critical role in ciliary transport. Loss of Cilk1 results in severe ciliopathy phenotypes, including polydactyly, edema, and cleft palate. However, the role of Cilk1 in tooth development remains unexplored. In this study, we investigated the role of Cilk1 in tooth development. Cilk1 was found to be expressed in both the epithelial and mesenchymal compartments of developing molars. Cilk1 deficiency resulted in altered ciliary dynamics, characterized by reduced frequency and increased length, accompanied by downregulation of Hh target genes, such as Ptch1 and Sostdc1, leading to the formation of diastemal supernumerary teeth. Furthermore, in Cilk1^-/-;PCS1-MRCS1^△/△ mice, which exhibit a compounded suppression of Hh signaling, we uncovered a novel phenomenon: diastemal supernumerary teeth can be larger than first molars. Based on these findings, we propose a progressive model linking Hh signaling levels to sequential changes in tooth patterning: initially inducing diastemal supernumerary teeth, then enlarging them, and ultimately leading to molar fusion. This study reveals a previously unrecognized role of Cilk1 in controlling tooth morphology via Hh signaling and highlights how Hh signaling levels shape tooth patterning in a gradient-dependent manner.
Animals ; Hedgehog Proteins/physiology* ; Mice ; Signal Transduction/physiology* ; Tooth, Supernumerary ; Molar ; Cilia/physiology* ; Odontogenesis/physiology* ; Patched-1 Receptor ; Protein Serine-Threonine Kinases/physiology* ; Mice, Knockout ; Adaptor Proteins, Signal Transducing

OBJECTIVES: This study aimed to investigate the clinical characteristics of deciduous fused teeth and their inherited permanent-tooth performance type by using panoramic radiographs. METHODS: A total of 14 404 panoramic radiographs of 3- to 6-year-old children with deciduous dentition were collected from January 2023 to July 2024. The incidence of deciduous fused teeth was observed, and the abnormality of permanent teeth was recorded. SPSS 24.0 software was used for statistical analysis. RESULTS: The incidence of deciduous fused teeth was 3.06% (441/14 404). The order of dental position was as follows: mandibular deciduous incisors and cusp teeth fused (58.18%) > mandibular deciduous central and lateral incisors fused (30.91%) > maxillary deciduous central and lateral incisors fused (8.89%) > deciduous incisors and supernumerary teeth fused (2.02%). Deciduous fused teeth were found in 226 boys and 215 girls, with no significant difference between the sexes (P>0.05). We observed one pair (87.76%, 387/441) and two pairs (12.24%, 54/441) of fused teeth (54/441), respectively. A total of 287 pairs of fusion teeth on the right side more than 208 pairs on the left side, and the difference between them was statistically significant (P<0.01). More fusion teeth existed in mandibular deciduous teeth (443 pairs) than in maxillary ones (54 pairs), and the difference between them was statistically significant (P<0.01). More unilateral deciduous teeth (387 subjects) were found than bilateral ones (54 subjects), and the difference between them was statistically significant (P<0.01). Three types of deciduous fused teeth with inherited permanent teeth were observed as follows: 1) 49.49% (245/495) of inherited permanent teeth was absent, 2) 46.67% (231/495) of inherited permanent teeth was not absent, and 3) the number of fused permanent teeth accounted for 3.84% (19/495). CONCLUSIONS The incidence of deciduous fused teeth was 3.06%, mostly occurring in the lower anterior teeth region, with no gender difference. One pair of fused teeth is commonly observed, more often on the right than the left. These fusions occur more frequently in the mandible than the maxillary, and unilateral cases are more common than bilateral ones. Deciduous fused teeth had a certain impact on inherited permanent teeth. Pediatric dentists should pay attention to and closely observe whether any abnormality exists in the permanent dentition for early detection to prevent the harm caused by deciduous fused teeth.
Humans ; Tooth, Deciduous/abnormalities* ; Male ; Child ; Female ; Child, Preschool ; Dentition, Permanent ; Radiography, Panoramic ; Fused Teeth/diagnostic imaging* ; Incisor/diagnostic imaging* ; Tooth, Supernumerary/diagnostic imaging* ; Incidence ; Mandible

Fused teeth are usually formed by the partial or complete fusion of two normal tooth germs during the development process and belong to dental developmental abnormalities. Fused teeth are relatively rare clinically, and those occurring in the posterior tooth area are even rarer. This article reports a case of fused teeth between the first permanent molar and the second permanent molar in the right mandible. This fused tooth had a complex root canal anatomical structure (seven root canals). The number and location of the root canals were analyzed by cone beam computed tomography, and root canal treatment was successfully completed with the assistance of microscope.
Humans ; Molar/diagnostic imaging* ; Mandible ; Dental Pulp Cavity/abnormalities* ; Cone-Beam Computed Tomography ; Root Canal Therapy/methods* ; Fused Teeth/surgery*

Ectodermal dysplasia is a group of hereditary diseases characterized by developmental defects of ectodermal structures. Its oral manifestations mainly center on congenital missing teeth, abnormal tooth morphology, and maxillofacial bone developmental disorders, which seriously affect the masticatory function, maxillofacial development, and mental health of affected children. In this article, the multidimensional diagnostic strategy system for children with ectodermal dysplasia and the related progress of early oral prosthodontic treatment methods were systematically reviewed to provide references for clinicians in the diagnosis and treatment of children with ectodermal dysplasia.
Child ; Humans ; Anodontia ; Ectodermal Dysplasia/diagnosis* ; Prosthodontics ; Tooth Abnormalities/therapy*

Dentinogenesis imperfecta is a dentin development disorder inherited in an autosomal dominant manner. It is rarely seen in clinical with a low incidence rate. We reported a case of dentinogenesis imperfecta referred to the Department of Pediatric Dentistry, Hospital of Stomatology, Lanzhou University. Investigation of the four-generation pedigree of the proband and review of relevant literature indicated that dentinogenesis imperfecta equally affects both genders and involves deciduous and permanent teeth with a high familial prevalence. By analyzing the clinical manifestations of dentinogenesis imperfecta and exploring early management strategies, this case study aims to enhance dentists' understan-ding and management of this condition to improve patients' quality of life.
Female ; Humans ; Male ; Dentinogenesis Imperfecta/genetics* ; Pedigree ; Quality of Life

Dental trauma is a common oral condition in children. For single-type trauma to young permanent teeth, timely treatment often results in a high survival rate for both the teeth and the pulp. However, in cases of complex dental trauma or when supernumerary teeth are impacted near the apex of the injured tooth, the prognosis is less predictable. This article reports a case of root fracture in an immature maxillary permanent central incisor combined with impacted supernumerary tooth in the apical region. After supernumerary tooth extraction and pulp revascularization therapy, the case demonstrated a good treatment outcome over a nearly 10-year follow-up period.
Child ; Humans ; Incisor/injuries* ; Maxilla ; Tooth Extraction ; Tooth Fractures/complications* ; Tooth Root/injuries* ; Tooth, Impacted/surgery* ; Tooth, Supernumerary/surgery*

OBJECTIVE: To investigate the clinical phenotype and genetic characteristics of a family with Dentinogenesis imperfecta type Ⅰ(DGI-Ⅰ). METHODS: Clinical data were collected from a patient with DGI-Ⅰ admitted to the Reproductive Medicine Department of the Affiliated Hospital of Jining Medical University in March 2024. Clinical and familial data were retrospectively collected. Peripheral blood samples (5 mL each) were obtained from the proband and her family members for genomic DNA extraction, followed by whole-exome sequencing (WES) and Sanger sequencing validation. The pathogenicity of the detected variants was assessed according to the Classification Standards and Guidelines for Genetic Variants formulated by the American Society of Medical Genetics and Genomics (ACMG) (hereinafter referred to as the "ACMG Guidelines"). The study was approved by the Ethics Committee of the Affiliated Hospital of Jining Medical University (Ethics No. 2024-08-C012), and written informed consent for clinical research were obtained from all participants. RESULTS: The proband, a 35-year-old female, presented with translucent yellow primary teeth and progressive browning, darkening, and loss of permanent teeth, without skeletal abnormalities. Affected family members exhibited similar phenotypes. Genetic testing revealed a heterozygous COL1A2 variant (c.1503+1G>A) in the patient and other affected members, while unaffected family members all lacked this variant. Based on the ACMG Guidelines, this variant was classified as likely pathogenic (PM4 + PP1_Strong + PM2_Supporting). CONCLUSION The COL1A2 c.1503+1G>A heterozygous variant is the disease-causing mutation in this family. Above finding has expanded the mutational spectrum of the COL1A2 gene and provided a basis for genetic counseling and diagnosis in similar cases.
Humans ; Female ; Dentinogenesis Imperfecta/genetics* ; Collagen Type I/genetics* ; Adult ; Pedigree ; Mutation ; Male ; Phenotype ; Exome Sequencing

OBJECTIVE: To investigate the clinical characteristics and genetic etiology of a Chinese pedigree affected with Hereditary dentin dysplasia type II (DD-II) due to variant of dentin sialophosphoprotein (DSPP) gene. METHODS: A child diagnosed with DD- II at the Third Clinical Division of Peking University Hospital of Stomatology in December 2021 and her family members were selected as study subjects. Clinical data were retrospectively analyzed. Saliva samples were collected from the proband, her parents and sister for genomic DNA extraction. Whole exome sequencing (WES) was carried out. Candidate variant was verified by Sanger sequencing and TOPO-TA cloning sequencing. The candidate variant was also subjected to bioinformatics analysis using Mutation Taster v2021. Secondary and tertiary structures of the wild-type and variant DSPP proteins were predicted with psipred v4.0 and PyMOL v2.3 software, respectively. The pathogenicity of the variant was classified based on the guidelines from American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of Peking University Hospital of Stomatology (Ethics No.: PKUSSIRB-202162021). RESULTS: The proband and her mother and sister had all exhibited typical clinical manifestations of hereditary DD-II. The primary dentition of the proband displayed yellowish brown discoloration, wear, and obliteration in the chamber and root canal, while the permanent teeth of the proband's sister and mother appeared nearly normal in both color and appearance, though with obliteration in the chamber and root canal. Her father showed normal dentition. WES identified a heterozygous c.1915_1918delAAGT, p.(Lys639Glnfs*674) frameshift variant in the DSPP gene. Sanger sequencing and TOPO-TA cloning sequencing confirmed the presence of this variant in the proband, the proband's sister, and the mother, while the proband's father was negative for the variant, indicating an autosomal dominant inheritance pattern. The variant was predicted to be pathogenic by Mutation Taster v2021. Prediction of the secondary structure of the DSPP protein showed that the variant has changed it from coil to helix. The tertiary structure prediction of the DSPP protein showed change of the spatial structure of the variant DSPP, with the loops in the variant region replaced by helices at multiple sites. Based on the guidelines from the ACMG, the variant was classified as pathogenic (PVS1+PM2_Supporting+PP1+PP4). CONCLUSION Phenotypic analysis and genetic testing of this family has clarified the clinical diagnosis of hereditary DD- II. The c.1915_1918delAAGT variant probably underlay the pathogenesis of DD-II in this family. Above results have expanded the phenotypic spectrum of the disease and may contribute to further clinical and genetic research on this disease.
Humans ; Pedigree ; Female ; Extracellular Matrix Proteins/chemistry* ; Male ; Sialoglycoproteins/chemistry* ; Dentin Dysplasia/genetics* ; Asian People/genetics* ; Phosphoproteins/chemistry* ; Child ; Mutation ; China ; Exome Sequencing ; Adult ; East Asian People