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1.
Braz Dent J ; 23(4): 367-72, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23207851

RESUMEN

This study evaluated by an in vitro model the effect of beverages on dental enamel previously subjected to erosive challenge with hydrochloric acid. The factor under study was the type of beverage, in five levels: Sprite® Zero Low-calorie Soda Lime (positive control), Parmalat® ultra high temperature (UHT) milk, Ades® Original soymilk, Leão® Ice Tea Zero ready-to-drink low-calorie peach-flavored black teaand Prata® natural mineral water (negative control). Seventy-five bovine enamel specimens were distributed among the five types of beverages (n=15), according to a randomized complete block design. For the formation of erosive wear lesions, the specimens were immersed in 10 mL aqueous solution of hydrochloric acid 0.01 M for 2 min. Subsequently, the specimens were immersed in 20 mL of the beverages for 1 min, twice daily for 2 days at room temperature. In between, the specimens were kept in 20 mL of artificial saliva at 37ºC. The response variable was the quantitative enamel microhardness. ANOVA and Tukey's test showed highly significant differences (p<0.00001) in the enamel exposed to hydrochloric acid and beverages. The soft drink caused a significantly higher decrease in microhardness compared with the other beverages. The black tea caused a significantly higher reduction in microhardness than the mineral water, UHT milk and soymilk, but lower than the soft drink. Among the analyzed beverages, the soft drink and the black tea caused the most deleterious effects on dental enamel microhardness.


Asunto(s)
Bebidas/clasificación , Esmalte Dental/patología , Ácido Clorhídrico/efectos adversos , Erosión de los Dientes/inducido químicamente , Animales , Bebidas/efectos adversos , Bebidas Gaseosas/efectos adversos , Bovinos , Esmalte Dental/efectos de los fármacos , Fluoruros/análisis , Dureza , Humedad , Concentración de Iones de Hidrógeno , Electrodos de Iones Selectos , Leche , Aguas Minerales/efectos adversos , Distribución Aleatoria , Saliva Artificial/química , Leche de Soja , Té/efectos adversos , Temperatura , Factores de Tiempo
2.
Rev Soc Bras Med Trop ; 43(5): 542-7, 2010.
Artículo en Portugués | MEDLINE | ID: mdl-21085866

RESUMEN

INTRODUCTION: Person-to-person transmission of HIV and other communicable diseases may be associated with human geographic mobility. This article evaluated the incidence of transmissible opportunistic diseases among AIDS cases that had been reported by municipalities in the Brazilian border area. METHODS: Brazilian border area municipalities were grouped into three cultural regions; the source data was AIDS cases registered with the Ministry of Health from 1990 to 2003, which were classified according to CDC-adapted, Rio de Janeiro/Caracas and death criteria; detected communicable opportunistic diseases were categorized into groups according to transmission: 1) inhalation agent; 2) contaminated water and/or food ingestion, and 3) interpersonal contact. The descriptive evaluation considered cultural region, years of schooling, sex and age group. RESULTS: Different AIDS incidence patterns were observed among groups of opportunistic diseases in each cultural region. The extreme southern region showed the greatest incidence of AIDS; the absolute incidence of female cases was greatest in the category of heterosexual transmission; the number of male cases was greatest among intravenous drug users; transmission was most frequent in the interpersonal contact group, particularly incidences of candidiasis; tuberculoses and pneumonias were most frequent in the inhalation agent transmission group; the contaminated water/food ingestion transmission group showed an unchanged pattern of absolute incidence. CONCLUSIONS: The Brazilian border area is a very important and heterogeneous geographic phenomenon; AIDS programs must recognize different cultural geographies.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/transmisión , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/transmisión , Infecciones Oportunistas Relacionadas con el SIDA/clasificación , Adolescente , Adulto , Distribución por Edad , Anciano , Brasil/epidemiología , Enfermedades Transmisibles/clasificación , Notificación de Enfermedades , Escolaridad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Am J Dent ; 20(2): 97-102, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17542203

RESUMEN

PURPOSE: To evaluate the micromorphology and surface roughness of sound and demineralized enamel and dentin treated with a 10% carbamide peroxide bleaching agent in situ for 3 weeks. METHODS: A 10% carbamide peroxide bleaching agent, Opalescence (OPA) was evaluated and a placebo agent (PLA) not containing carbamide peroxide, was used as a control group. Forty dental slabs [10 sound enamel slabs (SE), 10 demineralized enamel slabs (DE), 10 sound dentin slabs (SD) and 10 demineralized dentin slabs (DD)] were randomly fixed on the facial surface of the first maxillary molars and second maxillary premolars of 10 volunteers. Demineralized enamel and dentin fragments were obtained by a dynamic model using demineralizing and remineralizing solutions. The volunteers were divided into two groups that received the bleaching or the placebo agent in different sequences and periods in a double blind 2 x 2 cross-over study with a wash-out period of 2 weeks. Roughness was performed on the slab surfaces followed by scanning electron microscope (SEM) evaluations. The images were evaluated by three calibrated examiners in duplicate in two different periods at x1500 (SE and DE) and x2000 original magnification (SD and DD). RESULTS: The Wilcoxon test showed significant differences in roughness for SE and DE treated with OPA or PLA, with rougher surfaces treated with OPA. No differences in roughness were observed for SD or DD treated with OPA or PLA. As the Kappa value for the inter-examiner agreement of SEM evaluations showed "moderate" reproducibility (0.41 < k< 0.60) in Period 1 and "substantial" (0.61 < k < 0.8) in Period 2, the latter was considered for the statistical analysis. The McNemar test showed no significant differences between SE, DE, SD or DD treated with OPA or PLA.


Asunto(s)
Oxidantes/efectos adversos , Peróxidos/efectos adversos , Blanqueamiento de Dientes/efectos adversos , Desmineralización Dental/inducido químicamente , Urea/análogos & derivados , Adulto , Peróxido de Carbamida , Esmalte Dental/efectos de los fármacos , Esmalte Dental/ultraestructura , Dentina/efectos de los fármacos , Dentina/ultraestructura , Combinación de Medicamentos , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Propiedades de Superficie/efectos de los fármacos , Urea/efectos adversos
4.
Am J Dent ; 19(5): 313-6, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17073210

RESUMEN

PURPOSE: To evaluate enamel permeability after external bleaching procedures. METHODS: The coronal portion of 75 human canines were covered with an acid resistant varnish, except for a 7.1 mm2 circular area on the labial surface and, according to a randomized complete block design, specimens were allocated to bleaching treatments using carbamide peroxide-containing agents (CP): 10%, 16% or 37%; or a 35% hydrogen peroxide product (HP). The control group was exposed to artificial saliva. The bleaching agents were applied following the manufacturer's recommendations over 21 days. In between bleaching exposures, specimens were stored in artificial saliva. Samples were then prepared according to a histochemical coloring method based on copper sulfate and dithiooxamide solutions. Digital images captured in an optical microscope were used to measure the percentage of copper ion penetration over the total enamel thickness on three sections taken from the exposed area. RESULTS: Analysis of Deviance showed a significant difference for the permeability values among groups (P = 0.046). Likelihood ratio test revealed that the use of the CP10% and HP35% agents caused significantly greater enamel permeability than did the control treatment. No significant differences in percentage of copper ion penetration were found among CP10%, CP16%, CP37% and HP35%. This in vitro study demonstrated that depending on the external bleaching procedure, enamel permeability may be increased.


Asunto(s)
Permeabilidad del Esmalte Dental/efectos de los fármacos , Peróxido de Hidrógeno/toxicidad , Oxidantes/toxicidad , Peróxidos/toxicidad , Blanqueamiento de Dientes/efectos adversos , Urea/análogos & derivados , Análisis de Varianza , Peróxido de Carbamida , Diente Canino , Combinación de Medicamentos , Humanos , Funciones de Verosimilitud , Urea/toxicidad
5.
J Biomed Mater Res B Appl Biomater ; 76(2): 381-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16206257

RESUMEN

This in situ study sought to evaluate the surface roughness evolution of resin composites finished and polished by different methods. A total of 108 rectangular-shaped specimens of a microfilled and a hybrid composite were cured against a Mylar matrix strip and left unpolished or instrumented with diamond burs, Al2O3-coated disks, Al2O3-impregnated UDMA disk, or with diamond burs followed by either one of the disks. After specimens had been profiled for the average surface roughness (Ra, microm), 18 volunteers wore a removable palatal appliance, which accommodated one specimen of each one of the 12 groups investigated. Surface roughness for up to 28 days of intraoral exposure was then measured at 1- or 7-day intervals. A split-plot ANOVA (alpha = 0.05) revealed a significant interaction between group and time. Tukey's test and regression analyses ascertained that initially finishing with burs only provided the roughest surface to both composites. Unpolished surfaces and those specimens polished with Al2O3-coated disks, regardless of previous use of diamond burs, attained smoother surface. The Al2O3-impregnated UDMA disk was capable of smoothening the surface of the hybrid material previously finished with diamond burs. The roughness achieved after finishing and polishing composites may be either smoothened or roughened after intraoral exposure. On the basis of the roughness range, it is advisable to use Al2O3-coated disks, regardless of whether diamond burs were previously used. Al2O3-impregnated UDMA disks (with or without previous application of diamond burs) may be also suitable for instrumenting hybrid restoratives.


Asunto(s)
Resinas Compuestas/química , Pulido Dental , Adolescente , Adulto , Óxido de Aluminio/química , Alisadura de la Restauración Dental , Femenino , Humanos , Masculino , Ensayo de Materiales , Microscopía de Fuerza Atómica , Distribución Aleatoria , Propiedades de Superficie
6.
Oper Dent ; 30(5): 608-16, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16268396

RESUMEN

This study evaluated the effects of 10% carbamide peroxide, carbopol and glycerin and their associations on microhardness over time on enamel and dentin. Eight treatment agents were evaluated: a commercial bleaching agent containing 10% carbamide peroxide (Opalescence 10% Ultradent), 10% carbamide peroxide, carbopol, glycerin, 10% carbamide peroxide + carbopol, 10% carbamide peroxide + glycerin, carbopol + glycerin and 10% carbamide peroxide + carbopol + glycerin. Three hundred and twenty human dental fragments, 80 sound enamel fragments (SE), 80 demineralized enamel fragments (DE), 80 sound dentin fragments (SD) and 80 demineralized dentin (DD) fragments, were exposed to the treatment agents (n=10). These agents were applied onto the surface of the fragments eight hours a day for 42 days. After eight hours, they were washed from the dental fragment surfaces after five back-and-forth movements with a soft bristle toothbrush under distilled and deionized running water. During the remaining time (16 hours per day), the fragments were kept in individual vials in artificial saliva. After the 42-day treatment period, the specimens were kept individually in artificial saliva for 14 days. Knoop microhardness measurements were performed at baseline, after eight hours, and 7, 14, 21, 28, 35 and 42 days, and 7 and 14 days post-treatment (corresponding to 49 and 56 days after the initial treatment agent applications). The non-parametric Kruskal-Wallis analysis showed significant differences among the agents at each time interval, except at baseline for sound and demineralized enamel and dentin. For SE, SD and DD, there was a decrease in microhardness values during treatment with all agents. There was a tendency towards lower microhardness values after treatment with carbopol and its associations for sound tissues. DD showed low microhardness values during and after treatment with CP and its associations. For DE, there was an increase in microhardness values during treatment with all agents and in the post-treatment phase. The baseline microhardness values were not recovered during the 14-day post-treatment phase. Opalescence 10%, carbamide peroxide, carbopol, glycerin and their associations may change the microhardness of sound and demineralized dental tissues, even in the presence of artificial saliva.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Dentina/efectos de los fármacos , Glicerol/efectos adversos , Peróxidos/efectos adversos , Polivinilos/efectos adversos , Blanqueamiento de Dientes/efectos adversos , Urea/análogos & derivados , Resinas Acrílicas , Peróxido de Carbamida , Combinación de Medicamentos , Dureza/efectos de los fármacos , Humanos , Diente Molar , Estadísticas no Paramétricas , Desmineralización Dental/inducido químicamente , Urea/efectos adversos
7.
Chest ; 125(2): 425-8, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14769719

RESUMEN

STUDY OBJECTIVE: To investigate the health-related quality of life (HRQL) profile of healthy young subjects with a short smoking history. DESIGN: Observational data at a single point in time. SETTING: Survey in two public universities. PARTICIPANTS: Seventy-seven smoker students without any comorbidities (39 men; mean +/- SD age, 20.5 +/- 2.0 years). A control group for HRQL measurements was composed of 97 healthy, never-smoker students from the same universities (55 men; mean +/- SD age, 20.6 +/- 2.0 years). INTERVENTIONS: All subjects were blinded to the study proposal, and answered autoapplicable forms dealing with healthy habits, smoking, and the 36-item short form questionnaire. RESULTS: Never-smokers showed higher mean quality-of-life scores than smokers in all domains. Statistically significant differences were observed for the domains physical functioning (86.5 +/- 12.9 vs 93.4 +/- 9.6), general health perceptions (64.3 +/- 19.8 vs 79.2 +/- 13.4), vitality (58.4 +/- 20.0 vs 64.6 +/- 16.5), social functioning (59.3 +/- 19.7 vs 76.3 +/- 19.6), and mental health index (66.4 +/- 21.1 vs 71.9 +/- 15.5). CONCLUSIONS: Healthy, light-to-moderate smokers with a short smoking history show significant impairment in physical and mental domains of HRQL in comparison to never-smokers. A better elucidation of these aspects may provide useful information for planning smoking-cessation interventions.


Asunto(s)
Actitud Frente a la Salud , Calidad de Vida , Fumar/epidemiología , Tabaquismo/epidemiología , Adolescente , Adulto , Distribución por Edad , Brasil/epidemiología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Estado de Salud , Indicadores de Salud , Encuestas Epidemiológicas , Humanos , Estilo de Vida , Masculino , Probabilidad , Valores de Referencia , Medición de Riesgo , Distribución por Sexo , Encuestas y Cuestionarios , Tabaquismo/diagnóstico
8.
J Am Dent Assoc ; 134(10): 1335-42, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14620012

RESUMEN

BACKGROUND: Different concentrations of carbamide peroxide (10 to 22 percent) have been used successfully as bleaching agents, but the adverse effects on enamel microhardness at different times are unknown. METHODS: The authors analyzed seven bleaching agents and a placebo. The agents were applied on the surface of human dental fragments for eight hours per day for 42 days and stored in vials containing artificial saliva. Microhardness measurements were performed at baseline, eight hours and seven, 14, 21, 28, 35 and 42 days, as well as at seven and 14 days after treatment had ended. RESULTS: Enamel treated with different bleaching agents or a placebo experienced a similar decrease in microhardness values over time, with the exception of fragments exposed to Opalescence PF 20 percent (Ultradent Products, South Jordan, Utah), or OPA20. Until the 49th day, the enamel exposed to OPA20 exhibited the lowest differences from baseline values. After 14 posttreatment days, enamel treated with placebo, Nite White 10 percent Excel (Discus Dental, Los Angeles), Nite White 16 percent Excel and Opalescence 10 percent exhibited the greatest differences from baseline values. An increase in enamel microhardness occurred at the end of the posttreatment period, although baseline values were not reached. CONCLUSIONS: Different concentrations of carbamide peroxide agents result in decreases in enamel microhardness. A post-bleaching period in artificial saliva resulted in recovery of baseline microhardness values (one agent) or an increase in values, although baseline values were not reached for these products. Clinical Implications. Higher concentrations of carbamide peroxide containing 0.11 percent ion fluoride can bleach teeth in a shorter period, with fewer hazardous effects on the enamel mineral content.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Oxidantes/efectos adversos , Peróxidos/efectos adversos , Blanqueamiento de Dientes/efectos adversos , Urea/análogos & derivados , Urea/efectos adversos , Peróxido de Carbamida , Combinación de Medicamentos , Dureza/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Oxidantes/administración & dosificación , Peróxidos/administración & dosificación , Saliva Artificial , Remineralización Dental , Urea/administración & dosificación
9.
Am J Dent ; 16(1): 42-6, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12744412

RESUMEN

PURPOSE: To evaluate the in vitro microhardness of enamel treated with a 10% carbamide peroxide agent and two desensitizing dentifrices at different bleaching times. MATERIALS AND METHODS: A 10% carbamide peroxide bleaching agent was evaluated (Rembrandt 10%) (REM). A placebo agent was used as a control group (PLA). The bleaching and the placebo agents were applied to human enamel dental fragments for 8 hours per day, followed by immersion for 5 minutes in a slurry solution of desensitizing dentifrices: Sensodyne (S) or Sensodyne Fluor (SF). During the remaining time, the enamel fragments were individually stored in 13.5 ml of artificial saliva. Knoop microhardness measurements were performed at baseline, 8 hours, 7, 14, 21, 28, 35 and 42 days of treatment and at 7 and 14 days of a post-treatment period. RESULTS: Analysis of variance and Tukey's test showed no differences in enamel microhardness for REM + SF (P=0.069) and PLA + SF (P=0.93) within each time interval. The dental fragments treated with REM + S and PLA + S showed an increase in microhardness values within each time interval (P<0.0001). There were significant differences among the treatment agents from the 28th to the 56th day. The use of 10% carbamide peroxide bleaching and a desensitizing dentifrice significantly increased the enamel microhardness values during the bleaching treatment and after 14 days after the completion of the treatment. After the post-treatment period, the enamel fragments treated with a placebo agent and with a 10% carbamide peroxide agent and with a desensitizing fluoride dentifrice maintained the baseline values.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Fluoruros/farmacología , Nitratos/farmacología , Peróxidos/farmacología , Fosfatos/farmacología , Urea/farmacología , Peróxido de Carbamida , Interpretación Estadística de Datos , Permeabilidad del Esmalte Dental/efectos de los fármacos , Dentífricos/farmacología , Dentífricos/uso terapéutico , Combinación de Medicamentos , Dureza/efectos de los fármacos , Humanos , Técnicas In Vitro , Polivinilos/farmacología , Blanqueamiento de Dientes/efectos adversos , Urea/análogos & derivados
10.
J Dent ; 30(5-6): 205-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12450711

RESUMEN

OBJECTIVE: The aim of this in vitro study was to evaluate the interaction between two sources of fluoride (restorative systems and dentifrices) in inhibiting artificial root caries development. METHODS: One hundred and eighty tooth segments were embedded in polyester resin, and sanded flat. Cylindrical cavities 1.0mm-deep and 1.5mm-diameter were prepared in root dentin and randomly restored by fluoride-containing restorative systems: Ketac-fil/Espe (Ke), Fuji II LC/GC Corp (Fj), F2000/3M (F2), Surefil/Dentsply (Su) or a control: Filtek Z250/3M (Z2). Ten experimental groups were made to test the association among the five restorative systems and two dentifrices: with F(-) (Sensodyne Baking Soda) or without F(-) (Sensodyne Original) (n=18). After surface polishing, a 1mm-wide margin around the restorations was demarcated and initial dentin surface Knoop microhardness values (KHN(i)) were obtained. The specimens were submitted to a pH-cycling model, and to applications of slurries of dentifrice. Afterwards the final dentin surface Knoop microhardness values (KHN(f)) were measured. RESULTS: The differences between KHN(i) and KHN(f), and the covariate KHN(i) were considered by the ANCOVA and Tukey's test (alpha=0.05). The interaction between restorative system and dentifrice was statistically significant (p=0.0026). All restorative systems provided some protection against artificial caries challenge when associated with the fluoride-containing dentifrice treatment. The means (standard deviation) of reductions in Knoop hardness values for systems associated with the fluoride-containing dentifrice were: Ke: 40.0(1.02)(a), Fj: 41.9(1.02)(b), F2: 43.3(1.04)(c), Su: 43.5(1.00)(c), Z2: 44.0(1.02)(c); and with the non-fluoride-containing dentifrice were: Ke: 42.9(1.02)(a), Fj: 44.7(1.01)(b), F2: 45.2(1.09)(bc), Su: 46.0(0.99)(c), Z2: 46.6(0.99)(c) (statistical differences were expressed by different letters). CONCLUSION: The cariostatic effect shown by the fluoride-containing dentifrice could enhance that shown by Ketac-fil and Fuji II LC, and could mask that shown by F2000.


Asunto(s)
Cariostáticos/uso terapéutico , Materiales Dentales/química , Restauración Dental Permanente , Dentífricos/uso terapéutico , Dentina/efectos de los fármacos , Fluoruros/uso terapéutico , Caries Radicular/prevención & control , Raíz del Diente/efectos de los fármacos , Análisis de Varianza , Cariostáticos/administración & dosificación , Compómeros/química , Resinas Compuestas/química , Pulido Dental , Dentina/ultraestructura , Combinación de Medicamentos , Fluoruros/administración & dosificación , Fluoruros/química , Cementos de Ionómero Vítreo/química , Dureza , Humanos , Concentración de Iones de Hidrógeno , Maleatos/química , Nitratos/química , Fosfatos/química , Cementos de Resina/química , Resinas Sintéticas/química , Estadística como Asunto , Raíz del Diente/ultraestructura
11.
Rev Saude Publica ; 36(3): 263-70, 2002 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-12131963

RESUMEN

OBJECTIVE: To analyze data on contraceptive use in the State of São Paulo, Brazil, collected by the Demographic and Health Survey (DHS) conducted in 1996. METHODS: The study data were compared to 1986 DHS and 1996 data on the Brazilian population. Contraceptive use among married or cohabiting women was evaluated focusing on age, number of children, schooling, and age and timing of female sterilization. Statistical analysis was performed using Student t-test and Kendall's non-parametric test. RESULTS: Unlike data on the Brazilian population, female sterilization rates were steady in the State of São Paulo during the studied period. The same contraceptive pattern is seen in both Brazil and São Paulo: women aged up to 30 years use largely pills; female sterilization predominates in women over 30, increasing with the number of children and decreasing with years of schooling. Male methods have also increased in recent years, being greater in São Paulo than in Brazil. São Paulo also shows a greater variety of reversible contraceptive methods. CONCLUSIONS: Although there were some differences, the prevalence of only two contraceptive methods in both Brazil and São Paulo suggests a tendency regarding the contraceptive methods offered and in reproductive health in the view of new regulations on family planning.


Asunto(s)
Anticoncepción/métodos , Anticonceptivos Femeninos , Adolescente , Adulto , Factores de Edad , Brasil , Anticoncepción/estadística & datos numéricos , Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Masculinos/administración & dosificación , Anticonceptivos Orales/administración & dosificación , Escolaridad , Femenino , Humanos , Masculino , Estado Civil , Persona de Mediana Edad , Paridad , Esterilización Reproductiva/métodos
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