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 analyze the clinical and genetic characteristics of pediatric patients with dual genetic diagnoses (DGD). Methods: Clinical and genetic data of pediatric patients with DGD from January 2021 to February 2022 in Peking University First Hospital were collected and analyzed retrospectively. Results: Among the 9 children, 6 were boys and 3 were girls. The age of last visit or follow-up was 5.0 (2.7,6.8) years. The main clinical manifestations included motor retardation, mental retardation, multiple malformations, and skeletal deformity. Cases 1-4 were all all boys, showed myopathic gait, poor running and jumping, and significantly increased level of serum creatine kinase. Disease-causing variations in Duchenne muscular dystrophy (DMD) gene were confirmed by genetic testing. The 4 children were diagnosed with DMD or Becker muscular dystrophy combined with a second genetic disease, including hypertrophic osteoarthropathy, spinal muscular atrophy, fragile X syndrome, and cerebral cavernous malformations type 3, respectively. Cases 5-9 were clinically and genetically diagnosed as COL9A1 gene-related multiple epiphyseal dysplasia type 6 combined with NF1 gene-related neurofibromatosis type 1, COL6A3 gene-related Bethlem myopathy with WNT1 gene-related osteogenesis imperfecta type XV, Turner syndrome (45, X0/46, XX chimera) with TH gene-related Segawa syndrome, Chromosome 22q11.2 microduplication syndrome with DYNC1H1 gene-related autosomal dominant lower extremity-predominant spinal muscular atrophy-1, and ANKRD11 gene-related KBG syndrome combined with IRF2BPL gene-related neurodevelopmental disorder with regression, abnormal movement, language loss and epilepsy. DMD was the most common, and there were 6 autosomal dominant diseases caused by de novo heterozygous pathogenic variations. Conclusions: Pediatric patients with coexistence of double genetic diagnoses show complex phenotypes. When the clinical manifestations and progression are not fully consistent with the diagnosed rare genetic disease, a second rare genetic disease should be considered, and autosomal dominant diseases caused by de novo heterozygous pathogenic variation should be paid attention to. Trio-based whole-exome sequencing combining a variety of molecular genetic tests would be helpful for precise diagnosis.
Humans ; Abnormalities, Multiple ; Retrospective Studies ; Intellectual Disability/genetics* ; Bone Diseases, Developmental/complications* ; Tooth Abnormalities/complications* ; Facies ; Muscular Dystrophy, Duchenne/complications* ; Muscular Atrophy, Spinal/complications* ; Carrier Proteins ; Nuclear Proteins

OBJECTIVES: This study aimed to investigate the clinical characteristics of congenital deciduous teeth absence and its permanent teeth performance type by using panoramic radiographs. METHODS: A total of 15 749 panora-mic radiographs of 3-6-year-old children with deciduous dentition were collected from January 2020 to December 2021. The incidence of congenital deciduous teeth absence was observed, and the abnormality of permanent teeth was recor-ded. SPSS 24.0 software was used for statistical analysis. RESULTS: The incidence of congenital deciduous teeth absence was 2.54% (400/15 749), which was found in 217 girls and 183 boys, and the difference between the genders was statistically significant (P=0.003). The absence of one and two deciduous teeth accounted for 99.75% (399/400) of the subjects. In addition, 92.63% (490/529) of mandibular deciduous lateral incisor was congenitally absent, 44.80% (237/529) of deciduous teeth was absent in the left jaw, and less than 55.20% (292/529) was absent in the right; the difference between them was statistically significant (P=0.017). The absence of 96.41% (510/529) deciduous teeth in the mandibular was significantly more than that of 3.59% (19/529) in the maxillary, and the difference between was statistically significant (P=0.000). Furthermore, 68.00% (272/400) and 32.00% (128/400) of deciduous teeth were absent in unilateral and bilateral, respectively, and the difference was statistically significant (P=0.000). Four types of congenital deciduous teeth absence with permanent teeth were observed as follows: 1) 73.91% (391/529) of permanent teeth was absent; 2) 20.60% (109/529) of permanent teeth was not absent; 3) the number of fused permanent teeth accounted for 4.91% (26/529); 4) the number of supernumerary teeth was 0.57% (3/529). CONCLUSIONS Although the absence of congenital deciduous teeth is less common than that of permanent teeth, it affects deciduous and permanent teeth to some extent. Dentists should pay attention to trace and observe whether abnormalities are present in the permanent teeth and take timely measures to maintain children's oral health.
Male ; Female ; Humans ; Tooth, Deciduous ; Dentition, Permanent ; Tooth, Supernumerary/epidemiology* ; Anodontia/etiology* ; Tooth Abnormalities/complications* ; Fused Teeth/epidemiology*