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1.
J Int Soc Prev Community Dent ; 4(Suppl 2): S126-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25558453

RESUMO

BACKGROUND: Presence of plaque may be the culprit for dental caries, gingivitis, periodontal problems, and halitosis. Many mechanical aids are practiced worldwide to remove or control plaque, including tooth brushes, dental floss, mouth rinses, and dentifrices. The objective of this clinical study was to investigate the effectiveness of herbal toothpaste (Dabur Red) in controlling plaque and gingivitis, as compared to conventional (non-herbal) dentifrice (Pepsodent). MATERIALS AND METHODS: In this study, 30 subjects aged 35-43 years with established gingivitis and at least 20 natural teeth, and having a probing depth <3 mm were investigated. After the washout period, plaque and gingival index (PI and GI, respectively) scores were assessed at days 0 and 30. Differences between groups were compared with Mann-Whitney U test and the mean scores of PI and GI by Wilcoxon test. Statistical difference between the weights of dentifrices tubes on days 0 and 30 was evaluated by Student's t-test. RESULTS: At the end of 30 days of the study, there was statistically significant difference between both the groups for plaque and gingival scores. CONCLUSION: After 30 days of trial, both test and control groups showed effective reduction of plaque and gingivitis, which was statistically significant. No adverse reactions to dentifrices products were observed during the trial. It was concluded that herbal dentifrice was as effective as non-herbal dentifrices in the control of plaque and gingivitis.

2.
J Contemp Dent Pract ; 13(4): 452-5, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23151691

RESUMO

AIM: The aim of the present study was to evaluate the in vitro caries preventive effect of fluoridated orthodontic resins under pH cycling with two types of acid demineralizing saliva. MATERIALS AND METHODS: Brackets were bonded to 120 extracted human premolars, using Rely-a-bond (n = 40), Tru- Bond (n = 40) and Ortho-one (n = 40) orthodontic bonding agents. Each group of resin was divided into 2 subgroups (n = 20): immersion in remineralizing artificial saliva for 14 days and acid saliva with pH 4.3. After 14 days of pH cycling the caries preventive effect on the development of white spot lesion was evaluated considering the presence of inhibition zones to white spot lesions using two scores: 0 = absence and 1 = presence. Kruskal-Wallis ANOVA and Mann-Whitney U tests were used. RESULTS: Formation of white spot lesions was observed only under pH cycling using acid saliva with pH 4.3; with Rely-a-bond and Tru-Bond being significantly more effective in preventing the appearance of white spot lesions effect than Ortho-one. CONCLUSION: The acidity of the demineralizing solution influenced the formation of white spot lesions around orthodontic brackets under highly cariogenic conditions. Rely-a-bond and Tru-bond presented higher caries-preventive effect than Orthoone. CLINICAL SIGNIFICANCE: The development of fluoride-containing materials cannot be regarded as a permanent means to control dental caries lesions, but a complement along with other preventive methods.


Assuntos
Cárie Dentária/prevenção & controle , Fluoretos/uso terapêutico , Cimentos de Resina/química , Cimentos de Resina/uso terapêutico , Análise de Variância , Bis-Fenol A-Glicidil Metacrilato/uso terapêutico , Colagem Dentária , Cárie Dentária/etiologia , Resinas Epóxi/uso terapêutico , Humanos , Braquetes Ortodônticos/efeitos adversos , Polietilenoglicóis/uso terapêutico , Saliva Artificial/efeitos adversos , Saliva Artificial/química , Estatísticas não Paramétricas
3.
Environ Monit Assess ; 184(8): 4889-901, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21912870

RESUMO

The level of arsenic (As) contamination and the geochemical composition of groundwater in Shuklaganj area located on the banks of the Ganges Delta of Kanpur-Unnao district were elucidated. Samples (n = 59) were collected from both India Mark II hand pumps (depth, 30-33 m) and domestic hand pump tube wells (10-12 m) located within 5 km from the banks of Ganges. Samples were analyzed for various parameters, including total inorganic As, sulfate, nitrate, alkalinity, ammonia, and iron. Hydrochemistry of the groundwater aquifer was studied through the trilinear plots between monovalent and divalent cations and anions. In Indian mark II hand pumps, arsenic concentration ranged from below detection limit to 448 µg/L. Most of the samples contained both As(III) and As(V). The pH of the samples ranged from 7.1 to 8.2. Except for a few, most of the samples were reducing in nature as evident by their negative oxidation reduction potentials. A positive correlation for arsenic with iron, ammonia, and dissolved organic carbon shows the probability of biodegradation of organic matter and reductive dissolution of Fe oxyhydroxide processes to leach As in aquifers. For confirmation of the suggested arsenic mobilization mechanism, the presence and absence of sulfate-reducing bacteria and iron-reducing bacteria were also tested.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , Índia , Cinética , Modelos Químicos , Nitratos/análise , Sulfatos/análise , Movimentos da Água
4.
Water Res ; 43(15): 3862-70, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19577786

RESUMO

A study on the removal of arsenic from real life groundwater using iron-chitosan composites is presented. Removal of arsenic(III) and arsenic(V) was studied through adsorption at pH 7.0 under equilibrium and dynamic conditions. The equilibrium data were fitted to Langmuir adsorption models and the various model parameters were evaluated. The monolayer adsorption capacity from the Langmuir model for iron chitosan flakes (ICF) (22.47+/-0.56 mg/g for As(V) and 16.15+/-0.32 mg/g for As(III)) was found to be considerably higher than that obtained for iron chitosan granules (ICB) (2.24+/-0.04 mg/g for As(V); 2.32+/-0.05 mg/g for As(III)). Anions including sulfate, phosphate and silicate at the levels present in groundwater did not cause serious interference in the adsorption behavior of arsenate/arsenite. The column regeneration studies were carried out for two sorption-desorption cycles for both As(III) and As(V) using ICF and ICB as sorbents. One hundred and forty-seven bed volumes of As(III) and 112 bed volumes of As(V) spiked groundwater were treated in column experiments using ICB, reducing arsenic concentration from 500 to <10 microg/l. The eluent used for the regeneration of the spent sorbent was 0.1M NaOH. The adsorbent was also successfully applied for the removal of total inorganic arsenic down to <10 microg/l from real life arsenic contaminated groundwater samples.


Assuntos
Arseniatos/análise , Arsenitos/análise , Quitosana/química , Ferro/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água/química , Adsorção , Arseniatos/química , Arsenitos/química , Recuperação e Remediação Ambiental , Fosfatos/química , Silicatos/química , Sulfatos/química
5.
Chemosphere ; 75(1): 83-91, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19135229

RESUMO

Threat to human health worldwide due to the natural contamination of arsenic in ground waters has led to extensive studies on factors controlling the distribution of arsenic and conditions leading to arsenic mobilization in different arsenic contaminated areas. Another aspect of the arsenic crisis, especially in South Asia, is the degree of spatial variability of ground water arsenic concentrations. Thus it becomes necessary to study the source and the processes involved in arsenic mobilization into ground water under such conditions. An arsenic contaminated area namely, Ballia district of UP was chosen for this study. A set of 56 samples were collected from India Mark II hand pumps (30-33 m depth) thrice in a year namely pre-monsoon (April '07), monsoon (July '06) and winter seasons (December '06). Nine samples were also collected from deep bore well hand pumps (66-75 m) to study the difference in geochemistry with the shallow pumps. Various water quality parameters like As(III), As(V), sulfate, nitrate, phosphate, bicarbonate, ammonia, were determined. Arsenic concentrations ranged from 0 to 468 microg L(-1) in ground water collected from depths of 30-33 m. In the deeper wells (66-75 m), arsenic concentrations ranged from 12 to 20 microg L(-1). Most samples contained both As(III) and As(V) and the concentration of As(III) was generally equal/higher than As(V). Not much variation of arsenic concentration was observed when sampled in summer, monsoon and winter seasons. Correlation studies among various water quality parameters revealed that reductive dissolution of FeOOH was the most probable mechanism for release of arsenic.


Assuntos
Arsênio/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Monitoramento Ambiental , Humanos , Índia , Estações do Ano
6.
J Hazard Mater ; 139(1): 103-7, 2007 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-16872741

RESUMO

Investigations were carried out on the defluoridation of fluoride-spiked ground water in domestic defluoridation units (DDU) with activated alumina (AA). Specific safe water yield (SSY) was determined as a function of AA amount and adsorbent depth. Reuse potential of exhausted AA was assessed by regenerating and reusing AA in multiple defluoridation cycles. High fluoride uptake capacity (FUC) from ground water matrix as well as retaining approximately 95% FUC up to five cycles showed the suitability of AA for defluoridation in DDU. SSY, liters of safe water/kg AA, was dependent on the AA amount and its depth. There was a significant decrease in SSY with the decrease in AA depth in different DDUs, even though the amount was maintained constant. The derived data from four DDUs, with 3-5 kg AA and depth ranging from 5 to 13 cm, showed that DDU design is one of the most important parameter to be considered for optimizing SSY.


Assuntos
Óxido de Alumínio/química , Fluoretação/instrumentação , Fluoretos/isolamento & purificação , Adsorção , Óxido de Alumínio/análise , Conservação dos Recursos Naturais , Fluoretos/análise , Concentração de Íons de Hidrogênio , Água/química
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