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Gamme d'année
1.
Odovtos (En línea) ; 26(1): 86-99, Jan.-Apr. 2024. tab, graf
Article Dans Anglais | LILACS, SaludCR | ID: biblio-1558621

Résumé

Abstract To assess the effect of different whitening toothpastes on enamel surface morphology, chemical profile and their whitening efficiency. Sixty teeth were divided into 5 groups (12 teeth/group); Gp I: brushed with no toothpaste. Gp II: brushed with Pearl-based toothpaste. Gp III: brushed with Charcoal- based toothpaste. Gp IV: brushed with Alumina-based toothpaste. Gp V: brushed with salt and lemon- based toothpaste. Each tooth was brushed with a bean sized toothpaste wetted with distilled water twice daily by using standard electronic toothbrush for four weeks. Enamel surface morphology, chemical profile and color of each tooth were investigated. Chemical profile results and color measurements were analyzed statistically. Gp I revealed normal enamel surface morphology and chemical profile. Gp II and Gp III demonstrated surface morphology close to Gp I with insignificant reduction in mineral content. Gp IV showed obvious shallowing of perikymata ridges, exposure of fish-scale appearance, with pits and depressions, alongside to the significant reduction in mineral content. Gp V presented the most enamel surface alteration with widening of prism sheath and depressions all over the surface, besides the highest significant reduction in mineral content. Gp V, followed by Gp IV, demonstrated the highest color and whiteness changes, followed by Gp III, then Gp II, while the lowest value was in Gp I. Salt & lemon-based toothpaste, followed by Alumina-based, exerted the most considerable changes in the morphology and chemical profile of the enamel surface, beside to the higher whitening effects on teeth than the others.


Resumen El objetivo del presente estudio fue evaluar el efecto de diferentes pastas dentales blanqueadoras sobre la morfología y el perfil químico de la superficie del esmalte y su eficacia blanqueadora. Sesenta dientes se dividieron en 5 grupos (12 dientes/grupo); Grupo I: cepillado sin pasta de dientes. Grupo II: cepillado con pasta de dientes a base de perlas. Grupo III: cepillado con pasta de dientes a base de carbón. Grupo IV: cepillado con pasta de dientes a base de Alúmina. Grupo V: cepillado con sal y pasta de dientes a base de limón. Cada diente se cepilló con una pasta de dientes del tamaño de un frijol humedecida con agua destilada dos veces al día utilizando un cepillo de dientes electrónico estándar durante cuatro semanas. Se investigaron la morfología de la superficie del esmalte, el perfil químico y el color de cada diente. Los resultados del perfil químico y las mediciones de color se analizaron estadísticamente. El Grupo I reveló una morfología de la superficie del esmalte y un perfil químico normales. Los Grupos II y III demostraron una morfología de superficie cercana a la del Grupo I con una reducción insignificante en el contenido mineral. El grupo IV mostró una evidente reducción de las crestas perikymatas, exposición de apariencia de escamas de pez, con hoyos y depresiones, junto con una reducción significativa en el contenido mineral. El grupo V presentó la mayor alteración de la superficie del esmalte con ensanchamiento de la vaina del prisma y depresiones en toda la superficie, además de una significativa reducción en el contenido mineral. El grupo V, seguido del grupo IV, demostró los mayores cambios de color y blancura, seguido del grupo III, luego el grupo II, mientras que el valor más bajo se presentó en el grupo I. Las pastas dentales a base de sal y limón, seguidas de las de alúmina, ejercieron los cambios más considerables en la morfología y el perfil químico de la superficie del esmalte, además de tener mayores efectos blanqueadores sobre los dientes que las demás.


Sujets)
Blanchiment dentaire/méthodes , Pâtes dentifrices/analyse , Émail dentaire , Techniques in vitro , Costa Rica
2.
Article Dans Anglais | WPRIM | ID: wpr-742277

Résumé

The present study was performed to observe histopathological effects of Oculotrema hippopotami Stunkard, 1924 infection in the eye of Hippopotamus amphibius, as well as to reveal new details of morphology and structural features of this monogenean and its comparison between 2 age stages of the parasite. This was done using both light and scanning electron microscopy, energy dispersive X-ray analysis (EDXA) and histopathology. The presence of a mixture of different generations (adult and sub-adult) in one host individual is common for Oculotrema Stunkard, 1924 in contrast to Polystoma Zeder, 1800. New metrical and graphical information obtained for adults and sub-adults compared with the previous studies. Here we show the presence of genital papillae in adults, metrical data on the distal part of the vas deferens. SEM micrographs of sperm ejaculatory structures and information about the flattened dorsal side of the body provided for the first time. Histopathological changes, such as necrosis and hemorrhage in host tissues as a result of O. hippopotami attachment structures are described. Structural analysis of different body parts of O. hippopotami of both age groups are also included. We show qualitative differences in the presence of hardening ions (S, P, Ca) in attachment structures (oral and haptor suckers) that increase with the age of the worm. The presence of sub-adults and adults on the same host, together with high levels of infection without high pathogenicity may account for Oculotrema being one of the most successful parasites among the Monogenea.


Sujets)
Adulte , Humains , Caractéristiques familiales , Hémorragie , Corps humain , Ions , Microscopie électronique à balayage , Nécrose , Parasites , Spermatozoïdes , Conduit déférent , Virulence
3.
Article Dans Coréen | WPRIM | ID: wpr-21206

Résumé

Silica contaminates frequently accidental wounds, but most silica-contaminated wounds heal uneventfully with normal scarring. In exceptional cases, a delayed hypersensitivity granulomatous reaction occurs at the site of the old scar. We report a case of silica granuloma in a 30-year-old female. She had presented four discrete asymptomatic, mildly erythematous to skin colored papules or deep-seated nodules on upper extremity and trunk for 3 months. Histopathology of right upper arm lesion showed a well-demarcated conglomerate nodule in subcutaneous tissue, composed of numerous non-caseating granulomas without central necrotic or hyalinized foci. Small polarizable birefractile fibrous particles are found within the nodule. Scanning electron microscopy(SEM) revealed thin needle shaped fibers with fracture ends and energy dispersive X-ray analysis(EDXA) of the fiber showed major peak for a silica component.


Sujets)
Adulte , Femelle , Humains , Bras , Cicatrice , Granulome , Substance hyaline , Hypersensibilité retardée , Aiguilles , Silice , Peau , Tissu sous-cutané , Membre supérieur , Plaies et blessures
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