teeth development Dotaz Zobrazit nápovědu
Tooth eruption follows a chronology corresponding to the date when the tooth erupts into the oral cavity. This date has been established in the literature and is subject to small variations depending on hereditary, endocrine and environmental features. Any disturbance during the development of the teeth -systemic or local- can affect not only the morphology, structure of dental hard tissues or number of teeth but also the time of eruption. The presence of a tooth in the mouth at birth or during the first month of life has been studied and denominated as natal and neonatal teeth. The aim of this paper is to review current information on this topic and to give treatment alternatives if it is necessary.
- MeSH
- extrakce zubů MeSH
- lidé MeSH
- novorozenec MeSH
- předmléčné zuby * MeSH
- prořezávání zubů MeSH
- zuby přespočetné MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
This paper describes tooth development in a basal squamate, Paroedura picta. Due to its reproductive strategy, mode of development and position within the reptiles, this gecko represents an excellent model organism for the study of reptile development. Here we document the dental pattern and development of non-functional (null generation) and functional generations of teeth during embryonic development. Tooth development is followed from initiation to cytodifferentiation and ankylosis, as the tooth germs develop from bud, through cap to bell stages. The fate of the single generation of non-functional (null generation) teeth is shown to be variable, with some teeth being expelled from the oral cavity, while others are incorporated into the functional bone and teeth, or are absorbed. Fate appears to depend on the initiation site within the oral cavity, with the first null generation teeth forming before formation of the dental lamina. We show evidence for a stratum intermedium layer in the enamel epithelium of functional teeth and show that the bicuspid shape of the teeth is created by asymmetrical deposition of enamel, and not by folding of the inner dental epithelium as observed in mammals.
- MeSH
- buněčná diferenciace MeSH
- ještěři embryologie MeSH
- modely u zvířat * MeSH
- odontogeneze fyziologie MeSH
- zubní sklovina embryologie MeSH
- zuby embryologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Klíčová slova
- RADIOGRAPHY, DENTAL *,
- MeSH
- lidé MeSH
- rentgendiagnostika zubní * MeSH
- zuby * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
In order to analyze and improve the dental age estimation in children and adolescents for forensic purposes, 22 age estimation methods were compared to a sample of 976 orthopantomographs (662 males, 314 females) of healthy Czech children and adolescents aged between 2.7 and 20.5 years. All methods are compared in terms of the accuracy and complexity and are based on various data mining methods or on simple mathematical operations. The winning method is presented in detail. The comparison showed that only three methods provide the best accuracy while remaining user-friendly. These methods were used to build a tabular multiple linear regression model, an M5P tree model and support vector machine model with first-order polynomial kernel. All of them have mean absolute error (MAE) under 0.7 years for both males and females. The other well-performing data mining methods (RBF neural network, K-nearest neighbors, Kstar, etc.) have similar or slightly better accuracy, but they are not user-friendly as they require computing equipment and the implementation as computer program. The lowest estimation accuracy provides the traditional model based on age averages (MAE under 0.96 years). Different relevancy of various teeth for the age estimation was found. This finding also explains the lowest accuracy of the traditional averages-based model. In this paper, a technique for missing data replacement for the cases with missing teeth is presented in detail as well as the constrained tabular multiple regression model. Also, we provide free age prediction software based on this wining model.
- Klíčová slova
- Age estimation, Data mining, Model, Population-specific standards,
- MeSH
- data mining MeSH
- dentice trvalá * MeSH
- dítě MeSH
- lidé MeSH
- lineární modely MeSH
- mladiství MeSH
- mladý dospělý MeSH
- neuronové sítě MeSH
- předškolní dítě MeSH
- rentgendiagnostika panoramatická MeSH
- rozhodovací stromy MeSH
- software MeSH
- support vector machine MeSH
- určení zubního věku metody MeSH
- zuby růst a vývoj MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
AIM: This study aimed to evaluate the relationship between intubation during the neonatal period and enamel defects in primary teeth of preterm infants. It was an observational, prospective, analytical and sampling of convenience. We selected 157 children who had average birth weight of 1656.3±627.8 g, gestational age of 31.7±2.7 weeks and the examination of chronological age 2.2±0.6 years old. METHODS: Clinical examination of the oral cavity showed that the frequency of enamel defects was higher (86.3%) among children intubated when compared to non-intubated children (13.7%). The enamel defects was found to be inversely proportional to gestational age. The intubation time was related to the probability of occurrence of DDE (P<0.001), in other words, the greater the number of days intubated, the greater the chance of DDE. In children intubated, hypoplasia mainly affected the upper teeth on the left side of the mouth. CONCLUSION: Tracheal intubation in the neonatal period is the main cause of enamel defects in primary teeth of children born preterm. The longer the duration of intubation, the greater the chance of developing dental enamel defect. The area of action during movement of the laryngoscope toggle corresponds to the region most affected by tooth enamel hypoplasia in children intubated, upper right central incisor, lateral incisor and upper left.
- MeSH
- časové faktory MeSH
- gestační stáří MeSH
- hypoplazie zubní skloviny epidemiologie etiologie MeSH
- intratracheální intubace škodlivé účinky MeSH
- kojenec MeSH
- lidé MeSH
- novorozenec nedonošený MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- prospektivní studie MeSH
- zuby mléčné patologie MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
The aim of this study is to evaluate the results of dentigerous cysts enucleation with preservation of cyst-associated teeth as a single procedure in a group of children and preadolescents. A retrospective case series of seven patients with 15 unerupted developing teeth associated with or adjacent to dentigerous cysts was conducted. Patients were treated using the uniform surgical protocol (cystectomy, preservation of cyst-associated teeth, without use of orthodontic traction, primary wound closure). The metric analysis of the cysts and unerupted teeth on CBCT and an evaluation of the state of involved teeth after the treatment was performed. The mean age of patients was 9.0 ± 2.1 years (range 5-12 years, median = 9 years). All teeth erupted spontaneously. No serious postoperative complications or recurrences of lesions were detected. The mean follow-up was 53.1 ± 15.7 months (range 25-71 months, median = 52 months). The cystectomy of dentigerous cysts with preservation of associated teeth may be considered an alternative to marsupialization in children and preadolescents.
- Klíčová slova
- Decompression, Dentigerous cyst, Enucleation, Marsupialization, Teeth eruption,
- MeSH
- dentigerózní cysta * MeSH
- dítě MeSH
- lidé MeSH
- lokální recidiva nádoru MeSH
- neprořezané zuby * MeSH
- předškolní dítě MeSH
- retrospektivní studie MeSH
- Check Tag
- dítě MeSH
- lidé 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
[Disorders in the continual development of permanent teeth]
- MeSH
- lidé MeSH
- nemoci zubů etiologie MeSH
- zuby mléčné * MeSH
- zuby růst a vývoj MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
6,043 children, who were ordinary patients and children of Caucasian population, were examined clinically and radiographically. 430 children were aged 7-10 years. Dental anomalies were diagnosed in 14.1% (61 children) of those observed between 7-10 years. We aimed at numerical anomalies (78.6% of children with anomalies), morphological anomalies (19.6% of children with anomalies), size anomalies (3.2% of children with anomalies) and combinations of diagnoses (1.4% reflects the combinations of teeth 2 times calculated in combinations of diagnoses). Congenital numerical variations, i.e. hypodontia and hyperodontia, are among the most common deviations of the permanent dentition. Both conditions can occur as isolated traits or in association with other syndromes. Many studies indicate that hereditary factors are involved in the aetiology of anomalies. Gen MSX1 involves a primary position in mediating interactions between epithelium and mesenchyme in the development of teeth. Occurrence of dental anomalies is not very frequent; problems can arise with diagnosis of those affected teeth. It can be done using Orthopantomogram or Computed Tomography and 3D reconstruction. Some of the children with anomalies may have difficulties in treatment of affected teeth but in most cases the prognosis is good.
- MeSH
- abnormality zubů epidemiologie MeSH
- dítě MeSH
- lidé MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
The aim of this work was to investigate the early development of the deciduous dentition and oral vestibule in the human embryonic lower jaw. Histological sections and three-dimensional reconstructions from prenatal weeks 6-9 were used. A continuous anlage for the oral vestibule did not exist in the mandible. In contrast to the upper jaw, where we previously observed that the dental and vestibular epithelia developed separately, two dento-vestibular bulges differentiated in the incisor region of the mandible. The lingual parts of each bulge were found to give rise to the respective central and lateral incisors, whereas the labial parts differentiated into the vestibular epithelium. In the canine and molar areas, the dental and vestibular epithelia originated separately. Later, the segments of the vestibular epithelium fused into the labial vestibular ridge, giving rise to the lower oral vestibule in the lip region. In the cheek region, the oral vestibule was found to originate in the mucosal inflection between the developing jaw and the cheek. A similar heterogeneous developmental base for the oral vestibule was also observed in the upper jaw. There is thus no general scheme for the early development of the dental and vestibular epithelia that applies to both the upper and lower jaws, and to both their anterior and posterior regions.
- MeSH
- embryonální vývoj fyziologie MeSH
- epitel embryologie ultrastruktura MeSH
- lidé MeSH
- mandibula embryologie ultrastruktura MeSH
- maxila embryologie ultrastruktura MeSH
- těhotenství MeSH
- ústa embryologie ultrastruktura MeSH
- zobrazování trojrozměrné metody MeSH
- zuby mléčné * MeSH
- zuby embryologie ultrastruktura MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH