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1.
Clin Oral Investig ; 28(7): 411, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963445

RESUMO

OBJECTIVES: The aim of this study was to investigate the impact of birth weight on tooth development in children aged 7-8 years. MATERIALS AND METHODS: This retrospective cohort study comprised 75 children born at Bint Al-Huda Hospital, Bojnurd, in 2013-2014. The children were categorized into three groups based on their birth weight: Normal Birth Weight (NBW), Low Birth Weight (LBW), and Very Low Birth Weight (VLBW). Panoramic radiographs were taken for orthodontic examination, and Demirjian's 8-teeth method was employed to determine dental age. The study compared dental and chronological age within each group. Data analysis utilized SPSS software version 26, employing One-way ANOVA and chi-square tests. Statistical significance was set at P ≤ 0.05. RESULTS: The mean difference in dental and chronological age for Very Low Birth Weight (VLBW) children was 0.22 ± 0.44 years, for Low Birth Weight (LBW) children it was 0.19 ± 0.45 years, and for Normal Birth Weight (NBW) children, it was 0.08 ± 0.46 years. Although the mean difference decreased with increasing birth weight, this trend did not achieve statistical significance (P = 0.55). Furthermore, no significant differences were observed between the weight groups (P = 0.529) or genders (P = 0.191).


Assuntos
Peso ao Nascer , Radiografia Panorâmica , Humanos , Feminino , Estudos Retrospectivos , Masculino , Criança , Determinação da Idade pelos Dentes/métodos , Recém-Nascido de Baixo Peso , Recém-Nascido , Dente/crescimento & desenvolvimento , Dente/diagnóstico por imagem
2.
BMC Oral Health ; 24(1): 761, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965503

RESUMO

BACKGROUND: Tooth autotransplantation (TAT) is a surgical procedure involving the extraction of a tooth from one location and its subsequent transplantation into another alveolar socket within the same individual. This innovative treatment approach holds significant promise. Nonetheless, the potential recipients exhibit a limited level of awareness and understanding of this procedure. This study investigated the knowledge, attitudes, and practices (KAP) among patients with combined dentition defects and non-functional impacted teeth toward TAT. METHODS: This web-based cross-sectional study was conducted between December 2022 and February 2023 at one hospital. A self-designed questionnaire was developed to collect demographic information of the patients and assess their knowledge, attitudes, and practices toward TAT. RESULTS: A total of 533 valid questionnaires were collected. The mean knowledge, attitude, and practice scores were 5.55 ± 2.38 (possible range: 0-10), 26.82 ± 2.46 (possible range, 8-40), and 27.45 ± 7.40 (possible range, 9-45), respectively. CONCLUSION: The participants had insufficient knowledge, negative attitudes, and passive practices toward TAT. Targeted interventions should be implemented to improve the understanding and practice of TAT among patients with dentition defects.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Dente Impactado , Transplante Autólogo , Humanos , Dente Impactado/cirurgia , Estudos Transversais , Feminino , Masculino , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Adolescente , Adulto Jovem , Idoso , Dente/transplante
3.
PeerJ ; 12: e17478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952976

RESUMO

Bolt's Farm is the name given to a series of non-hominin bearing fossil sites that have often been suggested to be some of the oldest Pliocene sites in the Cradle of Humankind, South Africa. This article reports the results of the first combined Uranium-Series and Electron Spin Resonance (US-ESR) dating of bovid teeth at Milo's Cave and Aves Cave at Bolt's Farm. Both tooth enamel fragments and tooth enamel powder ages were presented for comparison. US-ESR, EU and LU models are calculated. Overall, the powder ages are consistent with previous uranium-lead and palaeomagnetic age estimates for the Aves Cave deposit, which suggest an age between ~3.15 and 2.61 Ma and provide the first ages for Milo's Cave dates to between ~3.1 and 2.7 Ma. The final ages were not overly dependent on the models used (US-ESR, LU or EU), which all overlap within error. These ages are all consistent with the biochronological age estimate (<3.4->2.6 Ma) based on the occurrence of Stage I Metridiochoerus andrewsi. Preliminary palaeomagnetic analysis from Milo's Cave indicates a reversal takes place at the site with predominantly intermediate directions, suggesting the deposit may date to the period between ~3.03 and 3.11 Ma within error of the ESR ages. This further suggests that there are no definitive examples of palaeocave deposits at Bolt's Farm older than 3.2 Ma. This research indicates that US-ESR dating has the potential to date fossil sites in the Cradle of Humankind to over 3 Ma. However, bulk sample analysis for US-ESR dating is recommended for sites over 3 Ma.


Assuntos
Fósseis , Datação Radiométrica , Urânio , África do Sul , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Urânio/análise , Animais , Cavernas/química , Dente/química , Dente/anatomia & histologia , Esmalte Dentário/química
4.
BMC Med Imaging ; 24(1): 172, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992601

RESUMO

OBJECTIVES: In the interpretation of panoramic radiographs (PRs), the identification and numbering of teeth is an important part of the correct diagnosis. This study evaluates the effectiveness of YOLO-v5 in the automatic detection, segmentation, and numbering of deciduous and permanent teeth in mixed dentition pediatric patients based on PRs. METHODS: A total of 3854 mixed pediatric patients PRs were labelled for deciduous and permanent teeth using the CranioCatch labeling program. The dataset was divided into three subsets: training (n = 3093, 80% of the total), validation (n = 387, 10% of the total) and test (n = 385, 10% of the total). An artificial intelligence (AI) algorithm using YOLO-v5 models were developed. RESULTS: The sensitivity, precision, F-1 score, and mean average precision-0.5 (mAP-0.5) values were 0.99, 0.99, 0.99, and 0.98 respectively, to teeth detection. The sensitivity, precision, F-1 score, and mAP-0.5 values were 0.98, 0.98, 0.98, and 0.98, respectively, to teeth segmentation. CONCLUSIONS: YOLO-v5 based models can have the potential to detect and enable the accurate segmentation of deciduous and permanent teeth using PRs of pediatric patients with mixed dentition.


Assuntos
Aprendizado Profundo , Dentição Mista , Odontopediatria , Radiografia Panorâmica , Dente , Radiografia Panorâmica/métodos , Aprendizado Profundo/normas , Dente/diagnóstico por imagem , Humanos , Pré-Escolar , Criança , Adolescente , Masculino , Feminino , Odontopediatria/métodos
5.
Int J Biol Sci ; 20(9): 3557-3569, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993575

RESUMO

To investigate the cell linkage between tooth dentin and bones, we studied TGF-ß roles during postnatal dentin development using TGF-ß receptor 2 (Tgfßr2) cKO models and cell lineage tracing approaches. Micro-CT showed that the early Tgfßr2 cKO exhibit short roots and thin root dentin (n = 4; p<0.01), a switch from multilayer pre-odontoblasts/odontoblasts to a single-layer of bone-like cells with a significant loss of ~85% of dentinal tubules (n = 4; p<0.01), and a matrix shift from dentin to bone. Mechanistic studies revealed a statistically significant decrease in odontogenic markers, and a sharp increase in bone markers. The late Tgfßr2 cKO teeth displayed losses of odontoblast polarity, a significant reduction in crown dentin volume, and the onset of massive bone-like structures in the crown pulp with high expression levels of bone markers and low levels of dentin markers. We thus concluded that bones and tooth dentin are in the same evolutionary linkage in which TGF-ß signaling defines the odontogenic fate of dental mesenchymal cells and odontoblasts. This finding also raises the possibility of switching the pulp odontogenic to the osteogenic feature of pulp cells via a local manipulation of gene programs in future treatment of tooth fractures.


Assuntos
Dentina , Odontoblastos , Receptores de Fatores de Crescimento Transformadores beta , Transdução de Sinais , Fator de Crescimento Transformador beta , Dentina/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Odontoblastos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Camundongos , Dente/metabolismo , Osso e Ossos/metabolismo , Microtomografia por Raio-X , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Camundongos Knockout
6.
Biomed Res Int ; 2024: 8783660, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988904

RESUMO

Background: The stage of tooth formation is one of the most reliable indicators for predicting a patient's developmental age by radiographs. This study compared the accuracy of three distinct dental age estimation methods (Demirjian, Nolla, and Willems) in children aged 3-17 in the northern Iranian population. Methods: This cross-sectional study examined panoramic radiographs of 434 children aged 3-17 from Mazandaran Province, Iran, who had teeth 31-37 present on the left mandible. This study employed the Demirjian, Nolla, and Willems methods to estimate the dental age of the sample and compare it with the chronological age. The data were analyzed using SPSS v16. A paired t-test was used to compare chronological and dental ages. The Pearson correlation was used to correlate the chronological and dental ages. The errors of different methods were compared using the Wilcoxon test. P values < 0.05 were considered significant for all tests except Wilcoxon. For Wilcoxon, a P value < 0.017 was considered significant. Results: The three methods presented differing mean estimated ages. The Demirjian method delivered the highest mean, and all three methods differed significantly when compared in pairs. The results showed that the Demirjian method overestimated chronological age by 0.25 years (P < 0.001) in girls and 0.09 years (P = 0.28) in boys. The Willems method underestimated chronological age by 0.05 years (P = 0.47) in girls and 0.12 years (P = 0.13) in boys. The Nolla method underestimated chronological age by 0.41 years (P < 0.001) in girls and 0.40 years (P < 0.001) in boys. The accuracy of each method varied with the patient's age. Conclusion: According to the findings, the Willems method outperformed the Demirjian method, and the Demirjian method exceeded the Nolla method for estimating dental age in Iranian children aged 3-17. Overall, the Demirjian method overestimated the age of the study population, whereas the other two underestimated it.


Assuntos
Determinação da Idade pelos Dentes , Radiografia Panorâmica , Dente , Humanos , Criança , Feminino , Adolescente , Masculino , Irã (Geográfico) , Determinação da Idade pelos Dentes/métodos , Radiografia Panorâmica/métodos , Pré-Escolar , Estudos Transversais , Dente/diagnóstico por imagem , Dente/crescimento & desenvolvimento , Mandíbula/diagnóstico por imagem , Mandíbula/crescimento & desenvolvimento
7.
BMC Oral Health ; 24(1): 804, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014389

RESUMO

BACKGROUND: Tooth segmentation on intraoral scanned (IOS) data is a prerequisite for clinical applications in digital workflows. Current state-of-the-art methods lack the robustness to handle variability in dental conditions. This study aims to propose and evaluate the performance of a convolutional neural network (CNN) model for automatic tooth segmentation on IOS images. METHODS: A dataset of 761 IOS images (380 upper jaws, 381 lower jaws) was acquired using an intraoral scanner. The inclusion criteria included a full set of permanent teeth, teeth with orthodontic brackets, and partially edentulous dentition. A multi-step 3D U-Net pipeline was designed for automated tooth segmentation on IOS images. The model's performance was assessed in terms of time and accuracy. Additionally, the model was deployed on an online cloud-based platform, where a separate subsample of 18 IOS images was used to test the clinical applicability of the model by comparing three modes of segmentation: automated artificial intelligence-driven (A-AI), refined (R-AI), and semi-automatic (SA) segmentation. RESULTS: The average time for automated segmentation was 31.7 ± 8.1 s per jaw. The CNN model achieved an Intersection over Union (IoU) score of 91%, with the full set of teeth achieving the highest performance and the partially edentulous group scoring the lowest. In terms of clinical applicability, SA took an average of 860.4 s per case, whereas R-AI showed a 2.6-fold decrease in time (328.5 s). Furthermore, R-AI offered higher performance and reliability compared to SA, regardless of the dentition group. CONCLUSIONS: The 3D U-Net pipeline was accurate, efficient, and consistent for automatic tooth segmentation on IOS images. The online cloud-based platform could serve as a viable alternative for IOS segmentation.


Assuntos
Redes Neurais de Computação , Dente , Humanos , Dente/diagnóstico por imagem , Dente/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
8.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(3): 520-526, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38932538

RESUMO

The segmentation of dental models is a crucial step in computer-aided diagnosis and treatment systems for oral healthcare. To address the issues of poor universality and under-segmentation in tooth segmentation techniques, an intelligent tooth segmentation method combining multiple seed region growth and boundary extension is proposed. This method utilized the distribution characteristics of negative curvature meshes in teeth to obtain new seed points and effectively adapted to the structural differences between the top and sides of teeth through differential region growth. Additionally, the boundaries of the initial segmentation were extended based on geometric features, which was effectively compensated for under-segmentation issues in region growth. Ablation experiments and comparative experiments with current state-of-the-art algorithms demonstrated that the proposed method achieved better segmentation of crowded dental models and exhibited strong algorithm universality, thus possessing the capability to meet the practical segmentation needs in oral healthcare.


Assuntos
Algoritmos , Dente , Humanos , Dente/diagnóstico por imagem , Modelos Dentários , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
9.
Sci Adv ; 10(26): eadl5270, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941456

RESUMO

Rotator cuff repair surgeries fail frequently, with 20 to 94% of the 600,000 repairs performed annually in the United States resulting in retearing of the rotator cuff. The most common cause of failure is sutures tearing through tendons at grasping points. To address this issue, we drew inspiration from the specialized teeth of snakes of the Pythonoidea superfamily, which grasp soft tissues without tearing. To apply this nondamaging gripping approach to the surgical repair of tendon, we developed and optimized a python tooth-inspired device as an adjunct to current rotator cuff suture repair and found that it nearly doubled repair strength. Integrated simulations, 3D printing, and ex vivo experiments revealed a relationship between tooth shape and grasping mechanics, enabling optimization of the clinically relevant device that substantially enhances rotator cuff repair by distributing stresses over the attachment footprint. This approach suggests an alternative to traditional suturing paradigms and may reduce the risk of tendon retearing after rotator cuff repair.


Assuntos
Boidae , Manguito Rotador , Animais , Manguito Rotador/cirurgia , Boidae/fisiologia , Lesões do Manguito Rotador/cirurgia , Dente , Técnicas de Sutura/instrumentação , Fenômenos Biomecânicos , Humanos , Impressão Tridimensional
10.
Clin Oral Investig ; 28(6): 352, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822874

RESUMO

BACKGROUND: The relationship between tooth colour and individual satisfaction in oral aesthetics has long been a topic of interest. In this study, we utilized the fuzzy analytic hierarchy process (FAHP) to investigate the impacts of sex and age on tooth colour preference. The findings of this study should provide a scientific basis for oral aesthetic practice. METHODS: In the current study, a random selection method was employed, and a survey was completed by 120 patients. To obtain tooth colour data, standard tooth colour charts were used. Smile photos were taken as template images using a single-lens reflex camera. The FAHP was utilized to conduct a weight analysis of tooth colour preferences among patients of different sexes and age groups. RESULTS: There were significant differences in tooth colour preference based on sex and age. Men tend to prefer the B1 colour, while women may prioritize the aesthetic effects of other colours. Additionally, as patients age, their preferences for tooth colour become more diverse. These findings offer valuable insights for oral aesthetics practitioners, enabling them to better address the aesthetic needs of patients across different sexes and ages. This knowledge can aid in the development of more personalized treatment plans that align with patients' expectations. CONCLUSION: In this study, we utilized scientific analysis methods to quantify the popularity of different tooth colours among various groups of people. By doing so, we established a scientific foundation for clinical practice. The findings of this study offer valuable insights for oral aesthetic research, enhancing our understanding of tooth colour. Additionally, these findings have practical applications in the field of oral medicine, potentially improving patients' quality of life and overall oral health.


Assuntos
Estética Dentária , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Etários , Cor , Inquéritos e Questionários , Sorriso , Idoso , Adolescente , Fotografia Dentária , Dente , Preferência do Paciente
11.
Arch Oral Biol ; 165: 106026, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38875772

RESUMO

OBJECTIVE: This study aimed to reveal the effects of SET domain bifurcated 1 (SETDB1) on epithelial cells during tooth development. DESIGN: We generated conditional knockout mice (Setdb1fl/fl,Keratin14-Cre+ mice), in which Setdb1 was deleted only in epithelial cells. At embryonic day 14.5 (E14.5), immunofluorescence staining was performed to confirm the absence of SETDB1 within the epithelium of tooth embryos from Setdb1fl/fl,Keratin14-Cre+ mice. Mouse embryos were harvested after reaching embryonic day 13.5 (E13.5), and sections were prepared for histological analysis. To observe tooth morphology in detail, electron microscopy and micro-CT analysis were performed at postnatal months 1 (P1M) and 6 (P6M). Tooth embryos were harvested from postnatal day 7 (P7) mice, and the epithelial components of the tooth embryos were isolated and examined using quantitative RT-PCR for the expression of genes involved in tooth development. RESULTS: Setdb1fl/fl,Keratin14-Cre+ mice exhibited enamel hypoplasia, brittle and fragile dentition, and significant abrasion. Coronal sections displayed abnormal ameloblast development, including immature polarization, and a thin enamel layer that detached from the dentinoenamel junction at P7. Electron microscopic analysis revealed characteristic findings such as an uneven surface and the absence of an enamel prism. The expression of Msx2, Amelogenin (Amelx), Ameloblastin (Ambn), and Enamelin (Enam) was significantly downregulated in the epithelial components of tooth germs in Setdb1fl/fl,Keratin14-Cre+ mice. CONCLUSIONS: These results indicate that SETDB1 in epithelial cells is important for tooth development and clarify the relationship between the epigenetic regulation of SETDB1 and amelogenesis imperfecta for the first time.


Assuntos
Células Epiteliais , Histona-Lisina N-Metiltransferase , Camundongos Knockout , Odontogênese , Animais , Camundongos , Histona-Lisina N-Metiltransferase/genética , Células Epiteliais/metabolismo , Amelogenina , Microtomografia por Raio-X , Ameloblastos/metabolismo , Esmalte Dentário/anormalidades , Esmalte Dentário/embriologia , Dente/embriologia , Dente/crescimento & desenvolvimento , Microscopia Eletrônica , Reação em Cadeia da Polimerase em Tempo Real
12.
Neurosci Biobehav Rev ; 163: 105745, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825260

RESUMO

Studying infants in the past is crucial for understanding the evolution of human life history and the evolution of cooperation, cognition, and communication. An infant's growth, health, and mortality can provide information about the dynamics and structure of a population, their cultural practices, and the adaptive capacity of a community. Skeletal remains provide one way of accessing this information for humans recovered prior to the historical periods. Teeth in particular, are retrospective archives of information that can be accessed through morphological, micromorphological, and biogeochemical methods. This review discusses how the microanatomy and formation of teeth, and particularly enamel, serve as archives of somatic growth, stress, and the environment. Examining their role in the broader context of human evolution, we discuss dental biogeochemistry and emphasize how the incremental growth of tooth microstructure facilitates the reconstruction of temporal data related to health, diet, mobility, and stress in past societies. The review concludes by considering tooth microstructure as a biomarker and the potential clinical applications.


Assuntos
Evolução Biológica , Esmalte Dentário , Humanos , Esmalte Dentário/crescimento & desenvolvimento , Criança , Cognição/fisiologia , Dente/anatomia & histologia , Dente/crescimento & desenvolvimento , Dente/fisiologia , Lactente
13.
PLoS Genet ; 20(6): e1011326, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38857279

RESUMO

The development of ectodermal organs begins with the formation of a stratified epithelial placode that progressively invaginates into the underlying mesenchyme as the organ takes its shape. Signaling by secreted molecules is critical for epithelial morphogenesis, but how that information leads to cell rearrangement and tissue shape changes remains an open question. Using the mouse dentition as a model, we first establish that non-muscle myosin II is essential for dental epithelial invagination and show that it functions by promoting cell-cell adhesion and persistent convergent cell movements in the suprabasal layer. Shh signaling controls these processes by inducing myosin II activation via AKT. Pharmacological induction of AKT and myosin II can also rescue defects caused by the inhibition of Shh. Together, our results support a model in which the Shh signal is transmitted through myosin II to power effective cellular rearrangement for proper dental epithelial invagination.


Assuntos
Adesão Celular , Movimento Celular , Proteínas Hedgehog , Miosina Tipo II , Transdução de Sinais , Animais , Camundongos , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Adesão Celular/genética , Miosina Tipo II/metabolismo , Miosina Tipo II/genética , Movimento Celular/genética , Epitélio/metabolismo , Morfogênese/genética , Dente/metabolismo , Dente/crescimento & desenvolvimento , Células Epiteliais/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Regulação da Expressão Gênica no Desenvolvimento
14.
Fa Yi Xue Za Zhi ; 40(2): 112-117, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38847024

RESUMO

Dental age estimation is a crucial aspect and one of the ways to accomplish forensic age estimation, and imaging technology is an important technique for dental age estimation. In recent years, some studies have preliminarily confirmed the feasibility of magnetic resonance imaging (MRI) in evaluating dental development, providing a new perspective and possibility for the evaluation of dental development, suggesting that MRI is expected to be a safer and more accurate tool for dental age estimation. However, further research is essential to verify its accuracy and feasibility. This article reviews the current state, challenges and limitations of MRI in dental development and age estimation, offering reference for the research of dental age assessment based on MRI technology.


Assuntos
Determinação da Idade pelos Dentes , Imageamento por Ressonância Magnética , Dente , Humanos , Determinação da Idade pelos Dentes/métodos , Imageamento por Ressonância Magnética/métodos , Dente/diagnóstico por imagem , Dente/crescimento & desenvolvimento , Odontologia Legal/métodos
15.
Sci Rep ; 14(1): 11789, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866826

RESUMO

Pterosaur remains have been reported from every continent; however, pterosaur skeletons remain rare. A new pterosaur is presented here, Haliskia peterseni gen. et sp. nov., constituting the most complete specimen from Australia from the upper Albian Toolebuc Formation of the Eromanga Basin (Queensland, Australia). A combination of features, including the presence of a premaxillary crest and curved teeth, and the morphology of the scapulocoracoid, support its referral to Anhangueria. Haliskia can be distinguished from all other anhanguerian pterosaurs based on two dental characters: the 4th and 5th tooth pairs are smaller than the 3rd and 6th, and the 2nd and 5th alveoli are smaller than 3-4 and 6-8. Moreover, the hyoid is 70% the total length of the mandible. The phylogenetic analyses presented here place Haliskia within Anhangueria. In one analysis, Haliskia and Ferrodraco are resolved as sister taxa, with Tropeognathus mesembrinus sister to that clade. The other resolves Haliskia, Mythunga and Ferrodraco in a polytomy within Tropeognathinae. The new Australian pterosaur attests to the success of Anhangueria during the latest Early Cretaceous and suggests that the Australian forms were more taxonomically diverse and palaeobiogeographically complex than previously recognized.


Assuntos
Dinossauros , Fósseis , Filogenia , Animais , Fósseis/anatomia & histologia , Dinossauros/anatomia & histologia , Dinossauros/classificação , Austrália , Dente/anatomia & histologia
16.
Fa Yi Xue Za Zhi ; 40(2): 135-142, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38847027

RESUMO

OBJECTIVES: To investigate the application value of combining the Demirjian's method with machine learning algorithms for dental age estimation in northern Chinese Han children and adolescents. METHODS: Oral panoramic images of 10 256 Han individuals aged 5 to 24 years in northern China were collected. The development of eight permanent teeth in the left mandibular was classified into different stages using the Demirjian's method. Various machine learning algorithms, including support vector regression (SVR), gradient boosting regression (GBR), linear regression (LR), random forest regression (RFR), and decision tree regression (DTR) were employed. Age estimation models were constructed based on total, female, and male samples respectively using these algorithms. The fitting performance of different machine learning algorithms in these three groups was evaluated. RESULTS: SVR demonstrated superior estimation efficiency among all machine learning models in both total and female samples, while GBR showed the best performance in male samples. The mean absolute error (MAE) of the optimal age estimation model was 1.246 3, 1.281 8 and 1.153 8 years in the total, female and male samples, respectively. The optimal age estimation model exhibited varying levels of accuracy across different age ranges, which provided relatively accurate age estimations in individuals under 18 years old. CONCLUSIONS: The machine learning model developed in this study exhibits good age estimation efficiency in northern Chinese Han children and adolescents. However, its performance is not ideal when applied to adult population. To improve the accuracy in age estimation, the other variables can be considered.


Assuntos
Determinação da Idade pelos Dentes , Algoritmos , Povo Asiático , Aprendizado de Máquina , Radiografia Panorâmica , Humanos , Adolescente , Criança , Masculino , Feminino , Determinação da Idade pelos Dentes/métodos , Radiografia Panorâmica/métodos , China/etnologia , Pré-Escolar , Adulto Jovem , Mandíbula , Dente/diagnóstico por imagem , Dente/crescimento & desenvolvimento , Máquina de Vetores de Suporte , Árvores de Decisões , Etnicidade , População do Leste Asiático
17.
Fa Yi Xue Za Zhi ; 40(2): 143-148, 2024 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38847028

RESUMO

OBJECTIVES: To estimate adolescents and children age using stepwise regression and machine learning methods based on the pulp and tooth volumes of the left maxillary central incisor and cuspid on cone beam computed tomography (CBCT) images, and to compare and analyze the estimation results. METHODS: A total of 498 Shanghai Han adolescents and children CBCT images of the oral and maxillofacial regions were collected. The pulp and tooth volumes of the left maxillary central incisor and cuspid were measured and calculated. Three machine learning algorithms (K-nearest neighbor, ridge regression, and decision tree) and stepwise regression were used to establish four age estimation models. The coefficient of determination, mean error, root mean square error, mean square error and mean absolute error were computed and compared. A correlation heatmap was drawn to visualize and the monotonic relationship between parameters was visually analyzed. RESULTS: The K-nearest neighbor model (R2=0.779) and the ridge regression model (R2=0.729) outperformed stepwise regression (R2=0.617), while the decision tree model (R2=0.494) showed poor fitting. The correlation heatmap demonstrated a monotonically negative correlation between age and the parameters including pulp volume, the ratio of pulp volume to hard tissue volume, and the ratio of pulp volume to tooth volume. CONCLUSIONS: Pulp volume and pulp volume proportion are closely related to age. The application of CBCT-based machine learning methods can provide more accurate age estimation results, which lays a foundation for further CBCT-based deep learning dental age estimation research.


Assuntos
Determinação da Idade pelos Dentes , Tomografia Computadorizada de Feixe Cônico , Polpa Dentária , Aprendizado de Máquina , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Adolescente , Criança , Determinação da Idade pelos Dentes/métodos , Polpa Dentária/diagnóstico por imagem , Dente/diagnóstico por imagem , China , Incisivo/diagnóstico por imagem , Incisivo/anatomia & histologia , Feminino , Masculino , Algoritmos
18.
Stomatologiia (Mosk) ; 103(3): 59-66, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38904562

RESUMO

The stages of preoperative planning and surgical treatment of compromised teeth by the method of autotransplantation of a tooth are presented on the example of two clinical cases. The autotransplantation method can be considered an alternative to dental implantation when strictly adhering to the surgical protocol and careful selection of patients.


Assuntos
Implantação Dentária , Dente , Transplante Autólogo , Humanos , Implantação Dentária/métodos , Dente/transplante , Masculino , Feminino , Adulto
19.
Nat Commun ; 15(1): 5273, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902270

RESUMO

Vertebrates use the phosphate mineral apatite in their skeletons, which allowed them to develop tissues such as enamel, characterized by an outstanding combination of hardness and elasticity. It has been hypothesized that the evolution of the earliest vertebrate skeletal tissues, found in the teeth of the extinct group of conodonts, was driven by adaptation to dental function. We test this hypothesis quantitatively and demonstrate that the crystallographic order increased throughout the early evolution of conodont teeth in parallel with morphological adaptation to food processing. With the c-axes of apatite crystals oriented perpendicular to the functional feeding surfaces, the strongest resistance to uniaxial compressional stress is conferred along the long axes of denticles. Our results support increasing control over biomineralization in the first skeletonized vertebrates and allow us to test models of functional morphology and material properties across conodont dental diversity.


Assuntos
Evolução Biológica , Biomineralização , Fósseis , Dente , Biomineralização/fisiologia , Animais , Dente/metabolismo , Dente/química , Apatitas/metabolismo , Apatitas/química , Esmalte Dentário/química , Esmalte Dentário/metabolismo , Vertebrados
20.
Anat Histol Embryol ; 53(4): e13064, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38841825

RESUMO

There are different strains of laboratory mouse used in many different fields. These strains differ anatomically. In order to determine these anatomical differences, shape analysis was conducted according to species. CD-1, C57bl/6 and Balb-c strains were preferred to study these differences. Forty-eight adult mouse strains belonging to these strains were utilized. The bones were photographed and geometric morphometry was applied to these photographs. Principal Component Analysis was applied to determine shape variations. In Principal component 1 for cranium, CD-1 and C57bl/6 strain groups showed different shape variations, while Balb-c strain group showed similar shape variations to the other strain groups. Principal Component 1 for the mandible separated the CD-1 and C57bl/6 strain groups in terms of shape variation. Principal Component 2 explained most of the variation between the C57bl/6 and CD-1 lineage groups. In PC1 for molars, the CD-1 group showed a different shape variation from the other groups. Mahalanobis distances and Procrustes distances were measured using Canonical variance analysis to explain the differences between the lineage groups. These measurements were statistically significant. For cranium, in canonical variate 1, CD-1 group of mouse and Balb-c group of mouse were separated from each other. In canonical variate 2, C57bl/6 group of mouse were separated from the other groups. For mandible, Balb-c group of mouse in canonical variate 1 and CD-1 group of mouse in canonical variate 2 were separated from the other groups. For molars, CD-1 group of mouse in canonical variate 1 and Balb-c group of mouse in canonical variate 2 were separated from the other groups. It was thought that these anatomical differences could be caused by genotypic factors as well as dietary differences and many different habits that would affect the way their muscles work.


Assuntos
Mandíbula , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Crânio , Animais , Crânio/anatomia & histologia , Camundongos/anatomia & histologia , Mandíbula/anatomia & histologia , Camundongos Endogâmicos BALB C/anatomia & histologia , Camundongos Endogâmicos C57BL/anatomia & histologia , Dente/anatomia & histologia , Análise de Componente Principal , Especificidade da Espécie , Masculino
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