BACKGROUND: Reptiles exhibit a large heterogeneity in teeth morphology. The main variability comprises the different tooth shape, the type of tooth attachment to the underlying bone, or the ability to replace the teeth. FINDINGS: Here, we provide full datasets of microtomography scans and 3D models of reptilian dentitions and skulls. We selected representative species for each of 9 reptilian families on the basis of their characteristic dental features. Because there are ≥4 different types of tooth-bone attachments, ranging from the mammalian-like thecodont attachment found in crocodilians to the simple acrodont implantation observed in some lizards, we aimed to evaluate species with different types of tooth-bone attachments. Moreover, another interesting feature varying in reptilian species is the complexity of tooth shape or the number of tooth generations, which can be associated with the type of tooth attachment to the jawbone. Therefore, selected model species also include animals with distinct tooth morphology along the jaw or different number of tooth generations. The development of tooth attachment and relationship of the tooth to the jaw can be further analysed in detail on a large collection of pre-hatching stages of chameleon. Next, we introduce different possibilities for how these datasets can be further used to study tooth-bone relationships or tooth morphology in 3D space. Moreover, these datasets can be valuable for additional morphological and morphometric analyses of reptilian skulls or their individually segmented skeletal elements. CONCLUSIONS: Our collection of microcomputed tomography scans can bring new insight into dental or skeletal research. The broad selection of reptilian species, together with their unique dental features and high quality of these scans including complete series of developmental stages of our model species and provide large opportunities for their reuse. Scans can be further used for virtual reality, 3D printing, or in education.
- Klíčová slova
- 3D imaging, craniofacial bones, micro-CT, reptiles, skull, tooth replacement, tooth-bone attachment,
- MeSH
- dentice MeSH
- ještěři * anatomie a histologie MeSH
- lebka anatomie a histologie diagnostické zobrazování MeSH
- lidé MeSH
- rentgenová mikrotomografie MeSH
- savci MeSH
- zuby * anatomie a histologie diagnostické zobrazování MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Bone is a dynamic biological tissue that acts as the primary rigid support of the body. Several systemic factors are responsible for pathologies that negatively affect its structural attributes. Although the bone is in continuous renewal by osteogenesis, metabolic diseases are the most common affectations that alter its natural equilibrium. Different techniques based on ionizing radiation are used for the bone diagnosis restrictively. However, if these are not used adequately, the application could present risks for human health. In this paper, it is proposed and explored a new technique to apply an early-stage diagnosis of bone variations. The technique evaluates bone structural conditions from the teeth (used as probes) by applying a structural health monitoring (SHM) methodology. An experimental procedure is described to identify the stiffness variations produced by mechanical drillings done in prepared bone samples. The identification is carried out applying the electromechanical impedance technique (EMI) through a piezo-actuated device in the frequency spectrum 5-20kHz. Three bone samples with incorporated teeth (three teeth, two teeth, and one tooth) were prepared to emulate a mandibular portion of alveolar bone-PDL (periodontal ligament)-tooth system. Piezo-device was attached to the crown of the tooth with an orthodontic bracket allowing the teeth to act as probes. The electrical resistance measurements were computed with an electrical decoupling approach that improved the detection of the drillings; it was due to the increment of the sensitivity of the signals. The results showed that the bone mass reduction is correlated with statistical indices obtained in specific frequency intervals of the electrical resistance. This work suggests the possibility of a future application addressed to a bone diagnosis in a non-invasive way.
- Klíčová slova
- bio-monitoring, bone, electromechanical impedance, piezo-device, structural health monitoring, teeth,
- MeSH
- elektrická impedance MeSH
- kostní denzita * MeSH
- lidé MeSH
- mandibula diagnostické zobrazování MeSH
- periodontální vaz MeSH
- zuby * diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Objective: The aim of the present study was the comparison of the known chronological age of the studied subjects by dental age evaluated according to the developmental stages of seven permanent teeth in the lower left dental quadrant and to determine how much the child's dental age differs from its chronological age. Methods: Radiographs of 579 patients (288 boys and 291 girls), aged 3-16 years, from the database of the Radiological Clinic of the Second Medical Faculty of Charles University and the Motol University Hospital in Prague were reviewed. The patients were examined for different indications by cone beam computed tomography (CBCT). The evaluation of the developmental stages of the teeth was performed from generated panoramic images and reconstructed three-dimensional (3D) images. The developmental stages of the teeth were evaluated by Demirjian's method for dental maturity based on seven teeth of the lower left dental quadrant (Demirjian et al. 1973). The evaluated variables were mineralization and development of the dental crown, length of the root, and closure of the apical foramen. Results: The difference between chronological and dental age was -0.16 (standard deviation (SD) 1.68, p-value 0.7) in boys and -0.10 (SD 1.65, p-value 0.27) in girls, on average. These results confirm that the method is accurate. Low SD values express the precision of the evaluation. Conclusion: Use of reconstructed 3D images makes the evaluation of the maturation of teeth more accurate in comparison to the use of generated panoramic images. The development of teeth (with exception of third molars) was complete at the age of 16 in 97.3% of the studied subjects.
- MeSH
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- počítačová tomografie se spirálovým kuželovým svazkem * MeSH
- předškolní dítě MeSH
- rentgendiagnostika panoramatická MeSH
- sběr dat MeSH
- určení zubního věku * MeSH
- zuby * diagnostické zobrazování MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Menarche is an indicator frequently used to study variation in growth, development, and related health conditions among members of living populations. As a life event, menarche is often associated with changes in an individual's social identity. The reproductive lifespan, which for females starts with menarche, is a paramount feature of palaeodemographic studies. Determination of menarche status from the skeletal remains of individuals of past populations can be obtained by assessing the developmental status of the iliac crest, as well as the hand and wrist bones, which are, unlike teeth, often poorly recovered in bioarchaeological contexts. The present study seeks to evaluate the link between dental mineralization and menarche in a population of known menarche status. The relationship between permanent teeth mineralization and menarche status was investigated by using data of developing permanent teeth (167 radiographs) rated in accordance with the well-known standards of Demirjian et al. and Moorrees et al. collected among 73 living French females of known menarcheal status. Using correlation ratios, GLMM and CART algorithm, menarcheal status is correlated with mineralization of the premolars. Menarcheal status is predicted correctly for 92 and 77% of radiographs of the learning and validation samples, respectively. Although promising, the results require caution prior to generalization to other populations. The age of menarche in this particular sample may simply coincide with the development of the premolars in this particular sample. Therefore, further investigation applied to populations with various mean ages of menarche is required in order to provide new evidence of variation in human growth and development from the correspondence between the mineralization of the permanent teeth and menarche.
- Klíčová slova
- CART algorithm, GLMM, menarche, puberty, teeth development,
- MeSH
- algoritmy MeSH
- antropologie fyzická MeSH
- dítě MeSH
- fyziologická kalcifikace fyziologie MeSH
- lidé MeSH
- menarche fyziologie MeSH
- mladiství MeSH
- rentgendiagnostika panoramatická MeSH
- zuby anatomie a histologie diagnostické zobrazování fyziologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Dental development is frequently used to estimate age in many anthropological specializations. The aim of this study was to extract an accurate predictive age system for the Czech population and to discover any different predictive ability of various tooth types and their ontogenetic stability during infancy and adolescence. A cross-sectional panoramic X-ray study was based on developmental stages assessment of mandibular teeth (Moorrees et al. 1963) using 1393 individuals aged from 3 to 17 years. Data mining methods were used for dental age estimation. These are based on nonlinear relationships between the predicted age and data sets. Compared with other tested predictive models, the GAME method predicted age with the highest accuracy. Age-interval estimations between the 10th and 90th percentiles ranged from -1.06 to +1.01 years in girls and from -1.13 to +1.20 in boys. Accuracy was expressed by RMS error, which is the average deviation between estimated and chronological age. The predictive value of individual teeth changed during the investigated period from 3 to 17 years. When we evaluated the whole period, the second molars exhibited the best predictive ability. When evaluating partial age periods, we found that the accuracy of biological age prediction declines with increasing age (from 0.52 to 1.20 years in girls and from 0.62 to 1.22 years in boys) and that the predictive importance of tooth types changes, depending on variability and the number of developmental stages in the age interval. GAME is a promising tool for age-interval estimation studies as they can provide reliable predictive models.
- MeSH
- data mining metody MeSH
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- předškolní dítě MeSH
- průřezové studie MeSH
- regresní analýza MeSH
- rentgendiagnostika panoramatická MeSH
- statistické modely MeSH
- support vector machine MeSH
- určení zubního věku metody MeSH
- zuby anatomie a histologie diagnostické zobrazování MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- radiografie MeSH
- zuby diagnostické zobrazování růst a vývoj MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- časové faktory MeSH
- dítě MeSH
- lidé MeSH
- minerály metabolismus MeSH
- mladiství MeSH
- předškolní dítě MeSH
- prořezávání zubů MeSH
- radiografie MeSH
- zuby mléčné růst a vývoj MeSH
- zuby diagnostické zobrazování růst a vývoj metabolismus MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- předškolní dítě MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- minerály MeSH
- Klíčová slova
- TEETH/radiography *,
- MeSH
- lidé MeSH
- radiografie MeSH
- zuby diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Klíčová slova
- TEETH/radiography *,
- MeSH
- lidé MeSH
- radiografie MeSH
- zuby diagnostické zobrazování MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
