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1.
Braz. j. oral sci ; 21: e222812, jan.-dez. 2022. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1348712

RESUMO

Aim: To evaluate the influence of the parameters L* a* b* on the variation of the color of bovine tooth enamel submitted to artificial darkening, after simulated brushing, with whitening toothpastes containing blue covarine. Methods: To undertake this study in vitro, 60 specimens (SP) were divided into 6 groups (n=10): control group (CGwater) and 5 test groups (GT1-Colgate Total 12, GT2-Oral-B 3D White Perfection, GT3- Colgate Luminous Instant White, GT4-CloseUp White Diamond Attraction, GT5-Sorriso Xtreme White). The specimens were darkened with coffee and submitted to simulated brushing for 6, 12, and 24 months. The alteration in the color was evaluated using CIELAB parameters and the ΔL, Δa, Δb and ΔE were calculated. The data was analyzed through generalized linear models using the R program and considering a level of significance of 5%. Results: The parameters L*, a* and the ΔL, Δa obtained better results in the test group than in the control group. There were no statistical differences between CG and the test groups for the evaluation of the b* parameter. In the evaluation of the Δb, the GT3 differed statistically from the CG. In relation to the ΔE, all the group tests showed a variation in color statistically greater than that of the CG and the GT4 showed the greatest variation, not differing from the GT3 during the periods studied. Conclusion: The mechanical and optical whitening agents positively influenced the values L*a* and b*, as well as in its variations and in the ΔE. It is important to emphasize, however, that to analyze tooth whitening it is necessary to evaluate their parameters together


Assuntos
Dente , Cremes Dentais , Cor , Clareadores
2.
Br Dent J ; 232(11): 768, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35689049
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(6): 553-556, 2022 Jun 09.
Artigo em Chinês | MEDLINE | ID: mdl-35691997

RESUMO

Since the Society of Prosthodontics, Chinese Stomatological Association was widely soliciting opinions, a recommended application guideline which based on experimental research, clinical and evidence-based medicine results was formed after several discussions and revisions. This guideline formulates the standardized operation procedures for the restoration of tooth defects with gold alloys, in order to guide and standardize the clinical application of gold alloy restorations, to improve the clinical efficacy and long-term survival rate of gold alloy restorations, and to promote the clinical application of gold alloy technique for restoration of dental defects.


Assuntos
Ligas de Ouro , Dente , Restauração Dentária Permanente/métodos
4.
Ned Tijdschr Tandheelkd ; 129(6): 295-305, 2022 Jun.
Artigo em Holandês | MEDLINE | ID: mdl-35670463

RESUMO

A radiolucency, radiopacity or mixed lesion, identified on a radiograph is usually the result of an inflammation of endodontic origin. However, a periapical lesion is sometimes caused by primary bone pathology, predominantly manifesting at the apices of the teeth. Various intraosseous lesions can be projected across the apices, creating the impression of a causal relation with these teeth. An incorrect diagnosis can lead to 1 or more endodontic treatments being carried out unjustifiably. A thorough and detailed anamnesis, a complete extra- and intraoral examination, and a careful examination of the radiological imaging will result in a correct diagnosis in most cases. Knowledge of the differential diagnosis of periapical lesions is essential. In this article, the focus will be on periapical radiolucencies and how they can be distinguished from each other.


Assuntos
Dente , Diagnóstico Diferencial , Humanos , Inflamação/diagnóstico por imagem
5.
Stud Health Technol Inform ; 290: 684-688, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35673104

RESUMO

Panoramic images are one of the most requested exams by dentists for allowing the visualization of the entire mouth. Interpreting X-ray images is a time-consuming task in which misdiagnoses can occur due to the inexperience or fatigue of professionals. In this work, we applied different image enhancement techniques as a pre-processing step to determine which image features correlate with improvements in teeth detection in panoramic images using deep learning architectures. We contrasted the performance of five object-detection architectures using 300 panoramic images of a public dataset. We evaluated the enhancement in the pre-processing step and the detection performance. Quality and detection metrics were considered, and the cross-correlation between them was computed for every object-detection method contemplated. We observe the dependence of the detection performance with some image enhancement techniques, especially those that introduce less noise and preserve the global contrast of the image.


Assuntos
Aprendizado Profundo , Dente , Benchmarking , Radiografia Panorâmica , Raios X
6.
J Evid Based Dent Pract ; 22(2): 101706, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35718435

RESUMO

OBJECTIVES: At present there is no clear consensus whether systemic antibiotics should be administered at replantation of an avulsed permanent tooth. This systematic review and meta-analysis assessed the evidence on effectiveness and harms of the administration of systemic antibiotics at replantation of avulsed permanent teeth. METHODS: In August 2020 a systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, for systematic reviews, randomized controlled trials (RCT) and observational controlled studies in MEDLINE, PreMedline, Embase, and the Cochrane databases. The population of interest were medically fit patients with a replanted avulsed tooth. Main outcomes were tooth survival, periodontal healing, pulpal revascularization as well as (severe) adverse events. These outcomes were compared in patients who did and who did not receive systemic antibiotics. The GRADE methodology was used to assess the quality of evidence. RESULTS: The search yielded no RCTs, and none of the 7 included observational studies had the prime intent to investigate the effectiveness or harms of antibiotics. According to GRADE, the overall level of evidence was very low. The meta-analyses showed non-significant associations between the administration of systemic antibiotics on the one hand and tooth survival (1 study, RR = 3.70, 95% CI: 0.63-21.69), periodontal healing (meta-analysis of 6 studies RR: 1.07; 95% CI: 0.80-1.45), and pulpal revascularization (meta-analysis of 2 studies, RR: 0.36; 95% CI: 0.05-2.41) on the other hand. CONCLUSION: Currently there is no high-quality evidence to support the use of systemic antibiotics at replantation of avulsed permanent teeth. Hence, their routine use cannot be recommended in medically fit patients. Well-designed RCTs should be a priority on the research agenda.


Assuntos
Avulsão Dentária , Dente , Antibacterianos/uso terapêutico , Dentição Permanente , Humanos , Avulsão Dentária/cirurgia , Reimplante Dentário/métodos
7.
Sci Rep ; 12(1): 10203, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715512

RESUMO

Conodonts are an extinct group of primitive jawless vertebrates whose elements represent the earliest examples of a mineralized feeding apparatus in vertebrates. Their relative relationship within vertebrates remains unresolved. As teeth, conodont elements are not homologous with the dentition of vertebrates, but they exhibit similarities in mineralization, growth patterns, and function. They clearly represent an early evolutionary experiment in mineralized dentition and offer insight into analogous dentition in other groups. Unfortunately, analysis of functional performance has been limited to a handful of derived morphologies and material properties that may inform ecology and functional analysis are virtually unknown. Here we applied a nanoscale approach to evaluate material properties of conodont bioapatite by utilizing Atomic Force Microscopy (AFM) nanoindentation to determine Young's modulus (E) along multiple elements representing different ontogenetic stages of development in the coniform-bearing apparatus of Dapsilodus obliquicostatus. We observed extreme and systematic variation in E along the length (oral to aboral) of each element that largely mirrors the spatial and ontogenetic variability in the crystalline structure of these specimens. Extreme spatial variability of E likely contributed to breakage of elements that were regularly repaired/regrown in conodonts but later vertebrate dentition strategies that lacked the ability to repair/regrow likely required the development of different material properties to avoid structural failure.


Assuntos
Dentição , Dente , Animais , Evolução Biológica , Fósseis , Vertebrados
8.
Biomed Eng Online ; 21(1): 36, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35706023

RESUMO

Despite numerous clinical trials and pre-clinical developments, the diagnosis of cracked tooth, especially in the early stages, remains a challenge. Cracked tooth syndrome is often accompanied by dramatic painful responses from occlusion and temperature stimulation, which has become one of the leading causes for tooth loss in adults. Current clinical diagnostical approaches for cracked tooth have been widely investigated based on X-rays, optical light, ultrasound wave, etc. Advances in artificial intelligence (AI) development have unlocked the possibility of detecting the crack in a more intellectual and automotive way. This may lead to the possibility of further enhancement of the diagnostic accuracy for cracked tooth disease. In this review, various medical imaging technologies for diagnosing cracked tooth are overviewed. In particular, the imaging modality, effect and the advantages of each diagnostic technique are discussed. What's more, AI-based crack detection and classification methods, especially the convolutional neural network (CNN)-based algorithms, including image classification (AlexNet), object detection (YOLO, Faster-RCNN), semantic segmentation (U-Net, Segnet) are comprehensively reviewed. Finally, the future perspectives and challenges in the diagnosis of the cracked tooth are lighted.


Assuntos
Síndrome de Dente Quebrado , Dente , Adulto , Algoritmos , Inteligência Artificial , Síndrome de Dente Quebrado/diagnóstico , Humanos , Redes Neurais de Computação , Dente/diagnóstico por imagem
9.
Sci Rep ; 12(1): 9429, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676524

RESUMO

This study evaluates the accuracy and efficiency of automatic tooth segmentation in digital dental models using deep learning. We developed a dynamic graph convolutional neural network (DGCNN)-based algorithm for automatic tooth segmentation and classification using 516 digital dental models. We segmented 30 digital dental models using three methods for comparison: (1) automatic tooth segmentation (AS) using the DGCNN-based algorithm from LaonSetup software, (2) landmark-based tooth segmentation (LS) using OrthoAnalyzer software, and (3) tooth designation and segmentation (DS) using Autolign software. We evaluated the segmentation success rate, mesiodistal (MD) width, clinical crown height (CCH), and segmentation time. For the AS, LS, and DS, the tooth segmentation success rates were 97.26%, 97.14%, and 87.86%, respectively (p < 0.001, post-hoc; AS, LS > DS), the means of MD widths were 8.51, 8.28, and 8.63 mm, respectively (p < 0.001, post hoc; DS > AS > LS), the means of CCHs were 7.58, 7.65, and 7.52 mm, respectively (p < 0.001, post-hoc; LS > DS, AS), and the means of segmentation times were 57.73, 424.17, and 150.73 s, respectively (p < 0.001, post-hoc; AS < DS < LS). Automatic tooth segmentation of a digital dental model using deep learning showed high segmentation success rate, accuracy, and efficiency; thus, it can be used for orthodontic diagnosis and appliance fabrication.


Assuntos
Aprendizado Profundo , Dente , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Dente/diagnóstico por imagem
10.
Arch Oral Biol ; 140: 105465, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35662681

RESUMO

OBJECTIVE: This review aimed to present an overview of the effect of bone morphogenetic protein 4 (BMP4) on craniofacial and skeletal development, particularly the specific role of BMP4 in tooth development. DESIGN: The search for this narrative review was conducted in PubMed, Web of Science, Embase, and ScienceDirect using relevant keywords, including checking reference lists of journal articles by hand searching. RESULTS: Mutations or deletions of BMP4 cause tissue development defects in mice and humans, such as fragile bone, craniofacial deformity, cleft lip and palate, tooth development stagnation, and abnormal structure. CONCLUSIONS: BMP4 is a reliable and vital candidate to regulate the development of bones, craniofacies, and teeth. It also has high clinical application potential.


Assuntos
Fenda Labial , Fissura Palatina , Dente , Animais , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Fenda Labial/genética , Fissura Palatina/genética , Camundongos , Odontogênese/genética
11.
Nat Commun ; 13(1): 2390, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501345

RESUMO

Innovations relating to the consumption of hard prey are implicated in ecological shifts in marine ecosystems as early as the mid-Paleozoic. Lungfishes represent the first and longest-ranging lineage of durophagous vertebrates, but how and when the various feeding specializations of this group arose remain unclear. Two exceptionally preserved fossils of the Early Devonian lobe-finned fish Youngolepis reveal the origin of the specialized lungfish feeding mechanism. Youngolepis has a radically restructured palate, reorienting jaw muscles for optimal force transition, coupled with radiating entopterygoid tooth rows like those of lungfish toothplates. This triturating surface occurs in conjunction with marginal dentition and blunt coronoid fangs, suggesting a role in crushing rather than piercing prey. Bayesian tip-dating analyses incorporating these morphological data indicate that the complete suite of lungfish feeding specializations may have arisen in as little as 7 million years, representing one of the most striking episodes of innovation during the initial evolutionary radiations of bony fishes.


Assuntos
Ecossistema , Dente , Animais , Teorema de Bayes , Peixes/anatomia & histologia , Fósseis
12.
Nature ; 605(7911): 602-603, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35581413
13.
Biomater Sci ; 10(12): 3062-3087, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35543379

RESUMO

Dental enamel is the hardest tissue in the human body, providing external protection for the tooth against masticatory forces, temperature changes and chemical stimuli. Once enamel is damaged/altered by genetic defects, dental caries, trauma, and/or dental wear, it cannot repair itself due to the loss of enamel producing cells following the tooth eruption. The current restorative dental materials are unable to replicate physico-mechanical, esthetic features and crystal structures of the native enamel. Thus, development of alternative approaches to repair and regenerate enamel defects is much needed but remains challenging due to the structural and functional complexities involved. This review paper summarizes the clinical aspects to be taken into consideration for the development of optimal therapeutic approaches to tackle dental enamel defects. It also provides a comprehensive overview of the emerging acellular and cellular approaches proposed for enamel remineralization and regeneration. Acellular approaches aim to artificially synthesize or re-mineralize enamel, whereas cell-based strategies aim to mimic the natural process of enamel development given that epithelial cells can be stimulated to produce enamel postnatally during the adult life. The key issues and current challenges are also discussed here, along with new perspectives for future research to advance the field of regenerative dentistry.


Assuntos
Cárie Dentária , Dente , Esmalte Dentário , Humanos , Regeneração
14.
Acta Biomater ; 146: 306-316, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35552001

RESUMO

Vertebrate skin is a remarkable organ that supports and protects the body. It consists of two layers, the epidermis and the underlying dermis. In some tetrapods, the dermis includes mineralised organs known as osteoderms (OD). Lizards, with over 7,000 species, show the greatest diversity in OD morphology and distribution, yet we barely understand what drives this diversity. This multiscale analysis of five species of lizards, whose lineages diverged ∼100-150 million years ago, compared the micro- and macrostructure, material properties, and bending rigidity of their ODs, and examined the underlying bones of the skull roof and jaw (including teeth when possible). Unsurprisingly, OD shape, taken alone, impacts bending rigidity, with the ODs of Corucia zebrata being most flexible and those of Timon lepidus being most rigid. Macroscopic variation is also reflected in microstructural diversity, with differences in tissue composition and arrangement. However, the properties of the core bony tissues, in both ODs and cranial bones, were found to be similar across taxa, although the hard, capping tissue on the ODs of Heloderma and Pseudopus had material properties similar to those of tooth enamel. The results offer evidence on the functional adaptations of cranial ODs, but questions remain regarding the factors driving their diversity. STATEMENT OF SIGNIFICANCE: Understanding nature has always been a significant source of inspiration for various areas of the physical and biological sciences. Here we unravelled a novel biomineralization, i.e. calcified tissue, OD, forming within the skin of lizards which show significant diversity across the group. A range of techniques were used to provide an insight into these exceptionally diverse natural structures, in an integrated, whole system fashion. Our results offer some suggestions into the functional and biomechanical adaptations of OD and their hierarchical structure. This knowledge can provide a potential source of inspiration for biomimetic and bioinspired designs, applicable to the manufacturing of light-weight, damage-tolerant and multifunctional materials for areas such as tissue engineering.


Assuntos
Lagartos , Dente , Animais , Epiderme , Lagartos/anatomia & histologia , Pele/anatomia & histologia , Crânio
15.
Mater Sci Eng C Mater Biol Appl ; 135: 112670, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35577686

RESUMO

Nacre exhibited noticeable similarities in fundamental material buildup and biological characteristics with tooth hard tissue, so the present study aims to achieve bionic dentine remineralization by duplicating nacre's "bottom-up" assembly concept. Inspired by nacre's mineralization mechanism, the present project starts to synthesize a "seawater-like" mineralizing precursor medium, then monitor its in vitro dentinal tubules occlusion effect, acid-resistant stability, the "fingerprint" dynamic components change in real time on in vitro sensitive tooth model as well as its in vitro cellular biological response towards human dental pulp stem cells. For the further exploration, a single-layer fibrillar collagen model was established to simulate the exposed collagen of demineralized dentine to appraise its intrafibrillar mineralization effect. The results demonstrated that the application of "seawater-like" mineralizing precursor medium effectively occluded dentinal tubules, reduced dentine permeability, increased surface microhardness, provided certain acid-resistant stability and possessed favorable in-vitro biocompatibility. In addition, the dynamic procedure of hierarchical intrafibrillar nanocrystalline assembly was observed, which offered a clue to uncover its remineralizing mechanism. It is attainable to realize the biomimetic remineralization of human dentine via the "bottom-up" concept inspired by nacre structure duplication, suggesting great potential for providing dentists a therapeutic strategy to counter dentine hypersensitivity in the future.


Assuntos
Nácar , Dente , Biomimética , Dentina/química , Humanos , Remineralização Dentária
16.
Arch Oral Biol ; 140: 105449, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35588676

RESUMO

OBJECTIVE: This study aims to investigate the following aspects: i) presence of activity-induced dental modifications (AIDMs) in a medieval population from Pieve di Pava (Siena, central Italy); ii) sex-specific and age-specific distribution of AIDMs in the sample; iii) potential correlations between AIDMs and the tradi tional activities and cultural habits of rural communities in medieval Italy. DESIGN: The permanent teeth of 204 individuals buried at Pieve di Pava (10th-12th centuries AD) were systematically examined in order to assess the distribution of five types of AIDM, i.e. lingual surface attrition of the maxillary anterior teeth (LSAMAT), excessive occlusal load, grooving, notching, and chipping. RESULTS: Prevalence rates of LSAMAT, excessive occlusal load and grooving were low, whereas higher frequencies were recorded for the other types of AIDMs. Prevalence was higher in the male subsample for all the modifications recorded. Overall, the frequencies of AIDMs increased with age. CONCLUSIONS: The very low prevalence of LSAMAT was thought to be connected to leatherworking in the sample under study, while excessive occlusal load was interpreted as evidence that hard materials requiring preliminary chewing and softening were not regularly processed with teeth. The unique case of interproximal grooving in an old male individual may reflect the use of a toothpick for therapeutic purpose. Conversely, the very high prevalence of notching and chipping was taken as indicative of the processing of wool fibers. The sex-specific distribution of these AIDMs suggests that males performed activities involving the use of teeth more frequently than females.


Assuntos
Desgaste dos Dentes , Dente , Animais , Feminino , Humanos , Itália , Masculino , Prevalência , Desgaste dos Dentes/história
17.
J Dent ; 122: 104145, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35523378

RESUMO

OBJECTIVES: The aim of this study was to evaluate the use of digital bitewing radiographs using photostimulable phosphor (PSP) plates in the estimation of the true extension of proximal carious lesions. METHODS: The sample size was calculated to be 70 teeth. Adult patients with a minimum of one posterior tooth with primary proximal caries lesions were included. A preoperative bitewing radiograph was taken and the extension of the carious lesion was measured from the most prominent point on the adjacent sound tooth to the deepest axial point of the lesion. An experienced general dentist provided the restorative treatment and made a polyvinyl siloxane impression of the cavity preparation. Clinical caries extension was measured from the most prominent point of the adjacent tooth until the deepest boundary of the axial wall of the preparation on the impression. Postoperative radiographs were taken at the completion of restorative care. The bitewing radiographs were done using PSP plates and caries extension measurements were performed using measuring tools of the digital radiography software. Pairwise comparisons were made between preoperative and postoperative radiographs, and the true clinical depth measurements using paired t-tests. RESULTS: In total, 73 teeth from 44 subjects were included. A significant difference of 0.82 mm was found between preoperative radiographs and clinical measurements (p<0.001). Similarly, comparisons between preoperative and postoperative radiographic measurements showed significant differences of 0.99 mm (p<0.001). CONCLUSIONS: The study found that the true clinical extension of proximal caries after non-selective caries removal was significantly deeper than the preoperative radiographic extension assessment. This was not influenced by the tooth type, the location of the tooth, or the affected tooth surfaces. CLINICAL SIGNIFICANCE: When a non-selective caries removal strategy is adopted, clinicians should be aware that PSP bitewing radiographs underestimate the true clinical extension of proximal caries lesions. This will have an impact on clinicians' practice and restorative treatment decisions.


Assuntos
Cárie Dentária , Dente , Adulto , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Cárie Dentária/terapia , Preparo da Cavidade Dentária , Humanos , Radiografia Interproximal , Radiografia Dentária Digital , Dente/patologia
18.
Eur J Oral Sci ; 130(3): e12870, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35490397

RESUMO

This study aimed to measure real-time temperature changes in gold-restored teeth compared with intact teeth during the intake of hot and cold drinks. Sixteen molars, including eight natural intact teeth and eight restored teeth with gold inlays, were selected from the participants. Custom-made thermocouple sensors were attached to the coronal third of the buccal surface of teeth. Participants consecutively consumed hot and cold drinks according to a standardized regimen. Resting, maximum, and minimum temperatures; time to reach peak temperatures; and heating and cooling velocities were obtained. Statistical analysis was performed using independent two-sample t-test. Teeth with gold restorations showed a significantly higher maximum temperature (44.7 °C [SD 2.9]) than did natural teeth (40.5 °C [SD 1.2]) during hot water drinking and showed a lower minimum temperature (25.0 °C [SD 4.9]) than did natural teeth (31.5 °C [SD 3.1]) during cold water drinking. The heating and cooling rates for the teeth with gold restorations were two and three times higher than those of the natural teeth. Gold-restored teeth showed greater temperature change than intact teeth in terms of magnitude and velocity in response to temperature changes induced by hot and cold drinks.


Assuntos
Ouro , Dente , Temperatura Baixa , Temperatura Alta , Humanos , Dente Molar , Temperatura , Dente/fisiologia , Água
19.
Stomatologiia (Mosk) ; 101(3): 82-88, 2022.
Artigo em Russo | MEDLINE | ID: mdl-35640184

RESUMO

OBJECTIVE: The aim of the study is to analyze the features of motor patterns formation in the craniocirvical zone with occlusal and functional disorders of the craniomandibular system. MATERIALS AND METHODS: 281 patients (201 women and 80 men) were examined at the age from 21 to 32 years. Two groups of individuals were identified based on the short Gambur test. The first group (I) included persons with intact dentition and without signs of functional disorders (n=30). The second group (II) included persons with intact dentition and dysfunction of the craniomandibular system (CMS) (n=30). All patients were examined by a digital analysis of the occlusal relationship. A digital method of capturing and reconstructing movement was used to assess the motor patterns of the craniocervical zone. Analysis of functional occlusion showed that the first contact in persons with functional impairment is predominantly localized on the molars region (χ2=44.1; df=11, p=0.00001). RESULTS: In analysis of dynamic occlusion, the time exceed for reaching maximum intercuspation position significantly in group II instead of group I 0.127±0.072 sec and 0.261±0.091 sec (p<0.05). Disconnection time in group II was 0.443±0.096 sec, Which significantly differed from group I (p<0.05). Persons with CCM dysfunction head flexion was 11.00° [9.00°; 13.00°], which is significantly higher than in the comparison group 5.00° [5.00°; 5.50°]. In the transverse plane, an increase in the angle of lateroflexion in persons with functional impairments up to 11.00° [10.00°; 11.00°]. Correlation analysis showed the presence of a direct strong connection between the angle of flexion and the time of separation (r=0.76), as well as the time to reach the maximum intercuspation position (r=0.63). CONCLUSION: Thus, functional disorders in the form of occlusal aberrations lead to changes in the cervical spine and head position through the formation of new motor patterns.


Assuntos
Oclusão Dentária , Dente , Adulto , Vértebras Cervicais , Feminino , Humanos , Masculino , Dente Molar , Pescoço , Adulto Jovem
20.
Sci Rep ; 12(1): 7499, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525838

RESUMO

The molluscan phylum is the second specious animal group with its taxa feeding on a variety of food sources. This is enabled by the radula, a chitinous membrane with embedded teeth, one important autapomorphy. Between species, radulae can vary in their morphology, mechanical, and chemical properties. With regard to chemical composition, some taxa (Polyplacophora and Patellogastropoda) were studied extensively in the past decades, due to their specificity to incorporate high proportions of iron, calcium, and silicon. There is, however, a huge lack of knowledge about radular composition in other taxa. The work presented aims at shedding light on the chemistry by performing energy-dispersive X-ray spectroscopy analyses on 24 molluscan species, thereof two Polyplacophora, two Cephalopoda, and 20 Gastropoda, which was never done before in such a comprehensiveness. The elements and their proportions were documented for 1448 individual, mature teeth and hypotheses about potential biomineralization types were proposed. The presented work additionally comprises a detailed record on past studies about the chemical composition of molluscan teeth, which is an important basis for further investigation of the radular chemistry. The found disparity in elements detected, in their distribution and proportions highlights the diversity of evolutionary solutions, as it depicts multiple biomineralization types present within Mollusca.


Assuntos
Gastrópodes , Hepatófitas , Poliplacóforos , Dente , Animais , Evolução Biológica , Gastrópodes/anatomia & histologia , Moluscos/anatomia & histologia , Dente/anatomia & histologia
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