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1.
Orv Hetil ; 159(51): 2154-2161, 2018 12.
Artigo em Húngaro | MEDLINE | ID: mdl-30556409

RESUMO

Writing a constat is a professional skill required of every general physician and dentist. Constats are issued by healthcare providers on the investigating authority's, court's or injured person's request. This document is an official judicial evidence, a record of medical examination, and it is also a medical opinion which can determine the outcome of the subsequent legal process. Incomplete and incorrect injury descriptions make it difficult for forensic experts to form accurate and appropriate opinions. The authors examined 147 dental and oral surgical constats from the Universities of Pécs and Debrecen using multidisciplinary approach (according to terminological, dental, surgical, forensic and criminal legal aspects). Several medical reports contained mistakes in terms of inaccuracies and self-contradictions, terminology and professional medical practice. The documents included 352 injuries (11.1% of which were tooth injuries, 47.7% bone injuries and 41.2% soft-tissue injuries). The low number of attributes per injury (0.64 on average) indicates insufficient documentation. As a result of the comparative analysis, significant differences were found between the documentation of dental injuries and that of other bone injuries pertaining to their information content. We can state that physicians are most consistent when describing bone injuries, while they are less articulate about tooth injuries. The authors provide an overview of the legal consequences of injuries as well as the legal practice regarding tooth injuries in Germany and Austria, and recommend the creation of a nationwide, unified terminology for both dental and trauma departments on nasal and dental injuries. Orv Hetil. 2018; 159(51): 2154-2161.


Assuntos
Odontologia/métodos , Erros de Diagnóstico/estatística & dados numéricos , Prontuários Médicos/estatística & dados numéricos , Traumatismos Dentários/diagnóstico , Odontologia/normas , Feminino , Medicina Legal , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos Dentários/terapia
2.
Sci Adv ; 10(32): eado4555, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39110800

RESUMO

We use synchrotron x-ray tomography of annual growth increments in the dental cementum of mammaliaforms (stem and crown fossil mammals) from three faunas across the Jurassic to map the origin of patterns of mammalian growth patterns, which are intrinsically related to mammalian endothermy. Although all fossils studied exhibited slower growth rates, longer life spans, and delayed sexual maturity relative to comparably sized extant mammals, the earliest crown mammals developed significantly faster growth rates in early life that reduced at sexual maturity, compared to stem mammaliaforms. Estimation of basal metabolic rates (BMRs) suggests that some fossil crown mammals had BMRs approaching the lowest rates of extant mammals. We suggest that mammalian growth patterns first evolved during their mid-Jurassic adaptive radiation, although growth remained slower than in extant mammals.


Assuntos
Evolução Biológica , Fósseis , Mamíferos , Animais , Cemento Dentário/anatomia & histologia , Síncrotrons , Filogenia , Metabolismo Basal
3.
Sci Rep ; 11(1): 14672, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282170

RESUMO

Colonic crypts are tubular glands that multiply through a symmetric branching process called crypt fission. During the early stages of colorectal cancer, the normal fission process is disturbed, leading to asymmetrical branching or budding. The challenging shapes of the budding crypts make it difficult to prepare paraffin sections for conventional histology, resulting in colonic cross sections with crypts that are only partially visible. To study crypt budding in situ and in three dimensions (3D), we employ X-ray micro-computed tomography to image intact colons, and a new method we developed (3D cyclorama) to digitally unroll them. Here, we present, verify and validate our '3D cyclorama' method that digitally unrolls deformed tubes of non-uniform thickness. It employs principles from electrostatics to reform the tube into a series of onion-like surfaces, which are mapped onto planar panoramic views. This enables the study of features extending over several layers of the tube's depth, demonstrated here by two case studies: (i) microvilli in the human placenta and (ii) 3D-printed adhesive films for drug delivery. Our 3D cyclorama method can provide novel insights into a wide spectrum of applications where digital unrolling or flattening is necessary, including long bones, teeth roots and ancient scrolls.

4.
PLoS One ; 16(11): e0249743, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34735460

RESUMO

Cementum, the tissue attaching mammal tooth roots to the periodontal ligament, grows appositionally throughout life, displaying a series of circum-annual incremental features. These have been studied for decades as a direct record of chronological lifespan. The majority of previous studies on cementum have used traditional thin-section histological methods to image and analyse increments. However, several caveats have been raised in terms of studying cementum increments in thin-sections. Firstly, the limited number of thin-sections and the two-dimensional perspective they impart provide an incomplete interpretation of cementum structure, and studies often struggle or fail to overcome complications in increment patterns that complicate or inhibit increment counting. Increments have been repeatedly shown to both split and coalesce, creating accessory increments that can bias increment counts. Secondly, identification and counting of cementum increments using human vision is subjective, and it has led to inaccurate readings in several experiments studying individuals of known age. Here, we have attempted to optimise a recently introduced imaging modality for cementum imaging; X-ray propagation-based phase-contrast imaging (PPCI). X-ray PPCI was performed for a sample of rhesus macaque (Macaca mulatta) lower first molars (n = 10) from a laboratory population of known age. PPCI allowed the qualitative identification of primary/annual versus intermittent secondary increments formed by splitting/coalescence. A new method for semi-automatic increment counting was then integrated into a purpose-built software package for studying cementum increments, to count increments in regions with minimal complications. Qualitative comparison with data from conventional cementochronology, based on histological examination of tissue thin-sections, confirmed that X-ray PPCI reliably and non-destructively records cementum increments (given the appropriate preparation of specimens prior to X-ray imaging). Validation of the increment counting algorithm suggests that it is robust and provides accurate estimates of increment counts. In summary, we show that our new increment counting method has the potential to overcome caveats of conventional cementochronology approaches, when used to analyse three-dimensional images provided by X-ray PPCI.


Assuntos
Algoritmos , Cemento Dentário/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Síncrotrons , Tomografia Computadorizada por Raios X , Animais , Macaca mulatta
5.
J Anat ; 217(2): 126-34, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20557399

RESUMO

The periodontal ligament (PDL) is a highly vascularized soft connective tissue. Previous studies suggest that the viscous component of the mechanical response may be explained by the deformation-induced collapse and expansion of internal voids (i.e. chiefly blood vessels) interacting with liquids (i.e. blood and interstitial fluids) flowing through the pores. In the present work we propose a methodology by means of which the morphology of the PDL vascular plexus can be monitored at different levels of compressive and tensile strains. To this end, 4-mm-diameter cylindrical specimens, comprising layers of bone, PDL and dentin covered by cementum, were strained at stretch ratios ranging from lambda = 0.6 to lambda = 1.4 and scanned using synchrotron radiation-based computer tomography. It was concluded that: (1) the PDL vascular network is layered in two distinct planes of blood vessels (BVs): an inner layer (close to the tooth), in which the BVs run in apico-coronal direction, and an outer layer (close to the alveolar bone), in which the BVs distribution is more diffuse; (2) during tension and compression, the porosity tissue is kept fairly constant; (3) mechanical straining induces important changes in BV diameters, possibly modifying the permeability of the PDL and thus contributing to the viscous component of the viscoelastic response observed under compressive forces.


Assuntos
Ligamento Periodontal/anatomia & histologia , Animais , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/fisiologia , Bovinos , Microcirculação/fisiologia , Ligamento Periodontal/irrigação sanguínea , Ligamento Periodontal/diagnóstico por imagem , Ligamento Periodontal/fisiologia , Porosidade , Manejo de Espécimes/métodos , Estresse Mecânico , Síncrotrons , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia
6.
J R Soc Interface ; 17(172): 20200538, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33234064

RESUMO

Cementum is a mineralized dental tissue common to mammals that grows throughout life, following a seasonally appositional rhythm. Each year, one thick translucent increment and one thin opaque increment is deposited, offering a near-complete record of an animal's life history. Male and female mammals exhibit significant differences in oral health, due to the contrasting effects of female versus male sex hormones. Oestrogen and progesterone have a range of negative effects on oral health that extends to the periodontium and cementum growth interface. Here, we use synchrotron radiation-based X-ray tomography to image the cementum of a sample of rhesus macaque (Macaca mulatta) teeth from individuals of known life history. We found that increased breeding history in females corresponds with increased increment tortuosity and less organized cementum structure, when compared to male and juvenile cementum. We quantified structural differences by measuring the greyscale 'texture' of cementum and comparing results using principal components analysis. Adult females and males occupy discrete regions of texture space with no overlap. Females with known pregnancy records also have significantly different cementum when compared with non-breeding and juvenile females. We conclude that several aspects of cementum structure and texture may reflect differences in sexual life history in primates.


Assuntos
Síncrotrons , Dente , Animais , Cemento Dentário/diagnóstico por imagem , Feminino , Macaca mulatta , Masculino , Tomografia por Raios X
7.
Community Dent Oral Epidemiol ; 48(5): 364-370, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32420644

RESUMO

OBJECTIVES: To examine the association between third molars and orofacial pain. We hypothesized that impacted third molars are a cause of orofacial pain. METHODS: Magnetic resonance images of 1808 participants from two population-based cohorts from Northeastern Germany were analysed to define the status of third molars according to the Pell and Gregory classification. A self-reported questionnaire and a clinical dental examination were used to detect chronic and acute complaints of orofacial pain, masticatory muscle pain, migraine and other types of headache. Logistic regression models were used to analyse the associations between third molar status and orofacial pain. RESULTS: Individuals with impacted third molars in the maxilla had a higher chance of chronic orofacial pain than those with erupted third molars (odds ratio 2.19; 95% CI 1.19-4.02). No such association was detected for third molars in the lower jaw. Third molars were not associated with masticatory muscle pain, migraine or other types of headache. CONCLUSIONS: Impacted maxillary third molars might be a cause of chronic orofacial pain. Thus, physicians should consider the eruption/impaction status of third molars in their decision-making process when treating patients who complain of orofacial pain.


Assuntos
Dente Serotino , Dente Impactado , Dor Facial/epidemiologia , Dor Facial/etiologia , Alemanha , Humanos , Mandíbula , Dente Impactado/epidemiologia
8.
Nat Commun ; 11(1): 5121, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046697

RESUMO

Despite considerable advances in knowledge of the anatomy, ecology and evolution of early mammals, far less is known about their physiology. Evidence is contradictory concerning the timing and fossil groups in which mammalian endothermy arose. To determine the state of metabolic evolution in two of the earliest stem-mammals, the Early Jurassic Morganucodon and Kuehneotherium, we use separate proxies for basal and maximum metabolic rate. Here we report, using synchrotron X-ray tomographic imaging of incremental tooth cementum, that they had maximum lifespans considerably longer than comparably sized living mammals, but similar to those of reptiles, and so they likely had reptilian-level basal metabolic rates. Measurements of femoral nutrient foramina show Morganucodon had blood flow rates intermediate between living mammals and reptiles, suggesting maximum metabolic rates increased evolutionarily before basal metabolic rates. Stem mammals lacked the elevated endothermic metabolism of living mammals, highlighting the mosaic nature of mammalian physiological evolution.


Assuntos
Mamíferos/fisiologia , Répteis/fisiologia , Animais , Metabolismo Basal , Evolução Biológica , Fósseis/anatomia & histologia , Fósseis/história , História Antiga , Mamíferos/classificação , Filogenia , Tomografia por Raios X , Dente/anatomia & histologia , Dente/química
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