Search results for "tooth"
showing 10 items of 910 documents
Correlation of carnassial tooth size and body weight in recent carnivores (mammalia)
1988
The correlation between the lower carnassial crown area and the body weight is examined for modern carnivores. It is very high, but the ursids and felids show a relationship different from the other carnivore families. Some exceptions are discussed. The possibility of predicting body weight for fossils is given.
Cytotoxicity and dentin composition alterations promoted by different chemomechanical caries removal agents : a preliminary in vitro study
2021
Background The use of chemomechanical agents for caries removal has been indicated as a non-invasive treatment option; however, their possible deleterious effects on the dental-pulp complex have been insufficiently studied. This study assessed the direct cytotoxicity of two chemomechanical caries removal agents (Brix 3000™ - BX and Papacarie Duo™ - PD) on pulp cells from deciduous teeth, as well as to assess the morphology and chemical compositions of the dentin surface after the application of these materials. Material and methods The cells were seeded (50,000 cells/cm²) in a culture medium (DMEM with 10% fetal bovine serum - FBS). After 24 hours, the BX and PD materials were added to 1:20…
TGF-β superfamily signaling is essential for tooth and hair morphogenesis and differentiation
2007
Members of the transforming growth factor beta (TGF-beta) superfamily of signaling molecules are involved in the regulation of many developmental processes that involve the interaction between mesenchymal and epithelial tissues. Smad7 is a potent inhibitor of many members of the TGF-beta family, notably TGF-beta and activin. In this study, we show that embryonic overexpression of Smad7 in stratified epithelia using a keratin 5 promoter, results in severe morphogenetic defects in skin and teeth and leads to embryonic and perinatal lethality. To further analyze the functions of Smad7 in epithelial tissues of adult mice, we used an expression system that allowed a controlled overexpression of …
Ontogenetic development of the holocephalan dentition: Morphological transitions of dentine in the absence of teeth.
2021
Among the cartilaginous fishes (Chondrichthyes), the Holocephali are unique in that teeth are absent both in ontogeny and adult regenerative growth. Instead, the holocephalan dentition of ever-growing nonshedding dental plates is composed of dentine, trabecular in arrangement, forming spaces into which a novel hypermineralized dentine (whitlockin) is deposited. These tissue features form a variety of specific morphologies as the defining characters of dental plates in the three families of extant holocephalans. We demonstrate how this morphology changes through ontogenetic development with continuity between morphologies, through successive growth stages of the dentition represented by the …
Hot air stream reduces cytotoxicity of light-cured calcium hydroxide based cements
2019
Background The light-cured calcium hydroxide based cements have incomplete polymerization and unconverted monomers can cause pulp cell damage. The aim of this study was to evaluate the influence of a warm and hot air stream on the cytotoxicity of light-cured calcium hydroxide based cements. Material and methods The materials Dycal (conventional cement), Biocal, Hidrox-Cal, and Ultra-Blend Plus (light-cured calcium hydroxide cements) were submitted to cytotoxicity analysis after polymerization, without vs. with previous heat treatment with a warm (37°C) and a hot (60°C) air stream. Following polymerization, cements were maintained in culture medium for 24 hours and 7 days, and subjected to t…
Influence of resin cement shade on the color and translucency of zirconia crowns
2020
Background Zirconia crowns are highly attractive for clinicians, although have poor translucency when used as single restorations, in addition to unknown effect of resin cement shade on final cemented crown shade. This study aimed to assess effect of resin cement opacity on color replication potential of different zirconia frameworks with target tooth color, in addition to different zirconia crowns translucency evaluation. Material and methods Twenty-four zirconia crown restorations were fabricated to restore single central maxillary incisor for 8 patients, divided into 3 groups according to color and type of zirconia used (white Zr core, colored Zr core and monolithic HT Zrcowns). Each gro…
Transverse Asymmetries of the Maxilla Even in Healthy and Apparently Symmetrical Subjects
2021
In the formulation of an orthodontic treatment plan, the three-dimensional analysis of the dental arches represents a fundamental moment for the evaluation of all the morphological parameters necessary in order to have a correct and complete diagnosis. In this regard, the study of the dental arches on the horizontal plane is sometimes neglected or not thorough enough. When evaluating the transverse dimensions of the dental upper arche, the presence of an asymmetry is frequently found, and it means that an hemiarch is larger than the other. Furthermore, any variation in one of the three planes of space always involves an alteration also on the other two planes in order to have compensation. …
Mouse model for Charcot Marie-Tooth as a tool to better understand the disease
2016
Introducción La enfermedad de Charcot-Marie-Tooth (CMT) es uno de los trastornos neurológicos hereditarios más comunes que afecta a 17-40 de cada 100.000 personas según poblaciones; concretamente esta cifra se sitúa en 28 personas de cada 100.000 en España. La enfermedad recibe el nombre de los tres médicos que la identificaron por primera vez en 1886; Jean-Marie Charcot y Pierre Marie en París, Francia y Howard Henry Tooth en Cambridge, Inglaterra. La enfermedad de CMT, también conocida como neuropatía hereditaria motora y sensitiva o atrofia muscular del peroneo, abarca un grupo de trastornos que afectan los nervios periféricos. El fenotipo clásico incluye problemas en la marcha, déficit …
Morphological parameters as predictors of successful correction of Class III malocclusion
2001
The aim of the study was to assess pre-treatment cephalometric parameters and measurements of the size of the apical bases as predictors of successful orthodontic correction of Class III malocclusions. Pre- and post-treatment lateral cephalograms and study models of 80 completed Class III subjects were examined to obtain 23 cephalometric parameters taken mainly from the analyses of McNamara and Schwarz, and to measure the size of the apical bases. Success of occlusal correction was evaluated as the percentage change of peer assessment rating score during treatment, which was used as the dependent variable in multivariate statistical analyses testing the predictive value of the parameters as…
Efficacy of plasma rich in growth factor used for dry socket management : a systematic review
2019
Background The main aim of this systematic review was to assess the dry socket management using plasma rich in growth factor (PRGF) in terms of pain relief, alveolar fossa healing, inflammation, the incidence of dry socket. Material and Methods PubMed, Cochrane Library, Elsevier Science Direct, China Biology Medicine (CBM), China National Knowledge Infrastructure (CNKI) and VIP database were searched for the related articles without language limitation. Two reviewers independently searched and evaluated relevant studies. This review has been registered in the website PROSPERO (CRD42018087252). Results 28 articles were retrieved on PubMed and 98 on other electronic databases in the initial s…