Spelling suggestions: "subject:"cleaner"" "subject:"leaner""
1 |
Benchmarking to trigger and sustain the introduction of cleaner production in small to medium sized enterprisesAltham, William Ashley January 2003 (has links)
This thesis investigates benchmarking (and associated capacity building activities) as a trigger for the diffusion and implementation of Cleaner Production. The critical success factors for the environmental benchmarking process are: The identification of gaps in environmental performance in areas important to the long-term future of the businesses; Providing and/or promoting the drivers to close the performance gaps; Ensuring business managers possess the ability and tools to close the performance gap. A program was developed implementing these factors and delivered to the drycleaning industry in Western Australia. This program identified large performance gaps for the different Eco-Efficiency indicators. The participants accepted the benchmarks (which are amended for 'economies of scale' if required) as suitable targets and committed their businesses to achieving these in their action plans. Economic benefits, managing environmental risk and maintaining their licence to operate were found to be important drivers. Participants on average reduced hazardous waste generation by 48%, improved their chemical efficiency by 30% and their energy efficiency by 9%, while individual business manager's levels of Eco-Efficiency improvements varied widely. The businesses with the higher levels of productivity and the greatest experience in the industry obtained the greatest improvements in Eco-Efficiency from the program. Furthermore, the business managers involved in the program had a significantly higher uptake of Cleaner Production in comparison with control groups, both inside the drycleaning sector as well as in 3 other sectors dominated by small to medium-sized enterprises. / This research indicates that benchmarking for small businesses needs to be part of an on-going industry specific capacity building program with the opportunity to network in a supportive atmosphere. When this is the case, improved environmental accounting practices and benchmarking can trigger and sustain the uptake of Cleaner Production to improve the Eco-Efficiency of small businesses.
|
2 |
Tecnologia mais limpa aplicada ao tratamento de água em sistemas de resfriamento abertos com recirculação / Cleaner technology applied to water treatment in open recirculating cooling systemsCésar Augusto Pereira 23 July 2007 (has links)
Os estudos destinados à aplicação de uma tecnologia mais limpa ao tratamento de águas em sistemas de resfriamento abertos com recirculação resultaram no desenvolvimento de uma filosofia de tratamento baseada na busca de uma operação com ciclo de concentração ideal. Assim, por meio do controle do balanço material no sistema de resfriamento, seria alcançado um nível de concentração em que a água de circulação apresentaria, naturalmente e ao mesmo tempo, baixa tendência à corrosão do ferro e baixa tendência à formação de incrustação de carbonato de cálcio. O tratamento com inibidores de corrosão e de formação de depósitos seria apenas complementar e, conseqüentemente, reduzido o emprego de produtos químicos para o condicionamento da água. O presente trabalho procura demonstrar que o critério de tratamento baseado apenas no índice de estabilidade não leva em conta o fato de que as espécies solúveis em água não se concentram de uma mesma forma, principalmente como decorrência de reações de conversão envolvendo o íon bicarbonato e de precipitação do íon cálcio. Como suporte desse trabalho, foram realizados ensaios de campo em um sistema de resfriamento aberto com recirculação em operação normal, porém sem tratamento químico da água. Foi possível, desse modo, observar a variação da concentração de cada espécie crítica presente na água com a vazão de descarga efetuada. Os resultados obtidos e o estudo realizado mostram que a metodologia tradicional pode apresentar desvios da realidade que podem comprometer a qualidade do tratamento, obrigando o emprego de maiores concentrações de produtos químicos para condicionamento da água, contrariando, assim, o próprio propósito original de execução de um tratamento dentro dos princípios de uma produção mais limpa. Este trabalho procura, ainda, salientar a importância qualitativa e quantitativa das espécies presentes, na água de reposição, na qualidade do tratamento, alertando que o emprego de reúso de água, como reposição de um sistema de resfriamento, deve ser criteriosamente analisado, pois uma água de má qualidade pode tornar o tratamento interno impraticável, exigindo a execução de um tratamento prévio muitas vezes inviável do ponto de vista econômico e causador de impacto ambiental / The studies for the use of cleaner technology to water treatment in open recirculating systems lead to the development of a treatment philosophy based on the search of an operation with ideal cycle of concentration. In this way, the material balance control in the cooling system, would be reached a concentration level which the circulating water exhibit naturally, and at the same time, low iron corrosion tendency and low calcium carbonate scale formation. The treatment using corrosion and deposit formation inhibitors would be only a complement, reducing the chemicals addition for the water conditioning. The present work intents to demonstrate that the treatment criteria based only on the stability index do not consider the fact that water-soluble species do not concentrate by the same way, mainly due to conversion reactions involving the carbonate ion and the calcium ion precipitation. To support this work, field tests were done in an open recirculating cooling system during its normal operation, without water chemical treatment. It was possible to observe the concentration variation of each critical species present in the water with blow-down flow rate. The obtained results and the study done showed that the traditional methodology can present deviations from the true values, which may affect the water treatment quality, leading to the use of higher concentration of chemical products for the water conditioning, in an opposite way of the original purpose for the treatment execution within the principles of a cleaner production. This work also emphasize the qualitative and quantitative species relevance, present at the make-up water, on the treatment quality, advising that the water reuse as make-up of a cooling system should be criteriously analyzed, because a low quality water can lead to an impracticable internal treatment, demanding a previous treatment many times economically unviable and causing environmental impacts
|
3 |
Investigation of the reasons for copper and gold loss in the cleaner tail, at Ok Tedi, Papua New GuineaErepan, Peter January 2004 (has links)
Ok Tedi Mining Limited generates a copper and gold concentrate from its porphyry and skarn ore deposits located at Mt. Fublian, Western Province, PNG. The predominant porphyry ore-type is blended with high grade skarn ores to optimize copper and gold feed grades to the concentrator. Current operation (2003) is to blend 80% porphyry with 20% skarn ores, resulting in an acceptable concentrate grade and recovery. However, when the proportion of skarn ore in the plant feed exceeds 20%, low flotation recovery is often observed. Approximately 20% of the copper and 30% gold losses occur through the rougher flotation circuit. However, losses via the cleaner tailing stream are 8% and 9% for copper and gold, respectively, and augment value mineral losses to the final tailing. It may be noted that the cleaner tailing stream contains value minerals which have already been successfully floated in the rougher section of the concentrator, and are therefore recoverable. This study has the objective of determining the reasons for copper and gold loss in the cleaner tailing. The focus is therefore on the cleaner flotation bank and related streams. The project strategy commenced with characterization of the cleaner circuit performance under various operating conditions. This would provide evidence for any proposed mechanisms to explain the losses of valuable minerals to the cleaner tailing. The second part of the project strategy was to evaluate potential methods for improvement of cleaner flotation performance via laboratory flotation tests. To complete the work, plant trials of methods showing benefit in the laboratory were conducted. / Characterisation surveys of the cleaner flotation bank were conducted as a function of ore blend, pulp and surface chemistry, mineralogy, flotation kinetics, particle size distribution, cleaner flotation cell hydrodynamic characterisation and residence time. These studies indicated that for greater than 20% pyrite skarn in the concentrator feed blend, lower than expected gold and copper recoveries were achieved in the cleaner bank. Pulp and surface chemical analytical techniques indicated layers of oxide coatings existed on all particles, depressing flotation. Oxide coatings had also resulted in the copper activation of pyrite (CuS rimming), making separation from copper sulfides difficult. Losses included coarse composite particles, also suggesting possible liberation issues. However, liberated copper sulfides were also lost, supporting the notion of depression via oxide coatings. Residence time calculations for the cleaner flotation bank suggested that the flotation capacity was less than adequate, particularly at high mill throughput rates. Hydrodynamic characterisation indicated improvements in cell hydrodynamics were warranted. In contrast to the oxidised ore feed blend described above, when less than 20% pyrite skarn was contained in the ore blend, high copper and gold recoveries were achieved in the cleaner bank. Laboratory tests suggested that increasing cleaner feed pH from 10.5 to 11.5, and 1 or collector addition to the cleaner feed, would result in improved cleaner flotation performance. These changes were trialed in the plant, with the pH adjustment being successful. High cleaner feed pH continues as a permanent modification to plant operating conditions.
|
4 |
Tecnologia mais limpa aplicada ao tratamento de água em sistemas de resfriamento abertos com recirculação / Cleaner technology applied to water treatment in open recirculating cooling systemsCésar Augusto Pereira 23 July 2007 (has links)
Os estudos destinados à aplicação de uma tecnologia mais limpa ao tratamento de águas em sistemas de resfriamento abertos com recirculação resultaram no desenvolvimento de uma filosofia de tratamento baseada na busca de uma operação com ciclo de concentração ideal. Assim, por meio do controle do balanço material no sistema de resfriamento, seria alcançado um nível de concentração em que a água de circulação apresentaria, naturalmente e ao mesmo tempo, baixa tendência à corrosão do ferro e baixa tendência à formação de incrustação de carbonato de cálcio. O tratamento com inibidores de corrosão e de formação de depósitos seria apenas complementar e, conseqüentemente, reduzido o emprego de produtos químicos para o condicionamento da água. O presente trabalho procura demonstrar que o critério de tratamento baseado apenas no índice de estabilidade não leva em conta o fato de que as espécies solúveis em água não se concentram de uma mesma forma, principalmente como decorrência de reações de conversão envolvendo o íon bicarbonato e de precipitação do íon cálcio. Como suporte desse trabalho, foram realizados ensaios de campo em um sistema de resfriamento aberto com recirculação em operação normal, porém sem tratamento químico da água. Foi possível, desse modo, observar a variação da concentração de cada espécie crítica presente na água com a vazão de descarga efetuada. Os resultados obtidos e o estudo realizado mostram que a metodologia tradicional pode apresentar desvios da realidade que podem comprometer a qualidade do tratamento, obrigando o emprego de maiores concentrações de produtos químicos para condicionamento da água, contrariando, assim, o próprio propósito original de execução de um tratamento dentro dos princípios de uma produção mais limpa. Este trabalho procura, ainda, salientar a importância qualitativa e quantitativa das espécies presentes, na água de reposição, na qualidade do tratamento, alertando que o emprego de reúso de água, como reposição de um sistema de resfriamento, deve ser criteriosamente analisado, pois uma água de má qualidade pode tornar o tratamento interno impraticável, exigindo a execução de um tratamento prévio muitas vezes inviável do ponto de vista econômico e causador de impacto ambiental / The studies for the use of cleaner technology to water treatment in open recirculating systems lead to the development of a treatment philosophy based on the search of an operation with ideal cycle of concentration. In this way, the material balance control in the cooling system, would be reached a concentration level which the circulating water exhibit naturally, and at the same time, low iron corrosion tendency and low calcium carbonate scale formation. The treatment using corrosion and deposit formation inhibitors would be only a complement, reducing the chemicals addition for the water conditioning. The present work intents to demonstrate that the treatment criteria based only on the stability index do not consider the fact that water-soluble species do not concentrate by the same way, mainly due to conversion reactions involving the carbonate ion and the calcium ion precipitation. To support this work, field tests were done in an open recirculating cooling system during its normal operation, without water chemical treatment. It was possible to observe the concentration variation of each critical species present in the water with blow-down flow rate. The obtained results and the study done showed that the traditional methodology can present deviations from the true values, which may affect the water treatment quality, leading to the use of higher concentration of chemical products for the water conditioning, in an opposite way of the original purpose for the treatment execution within the principles of a cleaner production. This work also emphasize the qualitative and quantitative species relevance, present at the make-up water, on the treatment quality, advising that the water reuse as make-up of a cooling system should be criteriously analyzed, because a low quality water can lead to an impracticable internal treatment, demanding a previous treatment many times economically unviable and causing environmental impacts
|
5 |
Design průmyslového vysavače / Design of Industrial Vacuum CleanerRašínová, Jitka January 2017 (has links)
The thesis is focused on design of industrial vacuum cleaner for use in workshops. The thesis includes design and technical reaserch of current vacuum cleaners. The main part contains original design solution with regard to technical and ergonomics requirements.
|
6 |
Mechanický čistící stroj / Mechanical cleaner-machineČejda, Robert January 2009 (has links)
The aim of my diploma thesis is to design a construction of a mechanical fine rack cleaner machine including an appropriate design of gear mechanism and its attachment to the frame. The cleaner machine is located in the inflow system of a turbine in front of the object of small hydro power station. The design of the construction of the cleaner machine will be based on a drawing documentation and a report with needed analytic and FEM calculations.
|
7 |
A needs assessment of the market for resource efficiency and cleaner production services in the Vaal Triangle / Theunis Christoffel BothaBotha, Theunis Christoffel January 2014 (has links)
Major energy-consuming countries implemented new laws on energy-efficiency during the course of 2013. The new energy-efficiency law make provision for a 16% reduction in energy intensity by 2015 in China. New law in the United States of America requires new fuel-economy standards. European Union law aims for a cut of 20% in energy demand for the countries forming part of the European Union. Japan, with the country's new energy strategy aims to decrease electricity demand with 10% by 2030 as stipulated in the new energy strategy.
South Arica is currently experiencing a shortage in electricity generating capacity and operates within its reserve margin. The construction of new power stations is in process to address the shortage but Eskom must finance these assets by increasing the electricity tariff. Electricity prices are predicted to double from 2013 to 2017. In addition to the tariff increases, the Energy Conservation Scheme (ECS) is also planned by Eskom whereby all electricity consumers have to reduce their electricity consumption by 10% or face penalties.
Energy efficiency initiatives in South Africa will help meet some of the country's social, economic, and environmental goals. These initiatives are important as they immediately tackle the problem of electricity shortages and are a cost-effective way of increasing available electricity supply.
The aim of this study was to determine the need for businesses in the Vaal Triangle to be resource efficient and practice clean production in order to be able to capitalise on that need. With the current knowledge and technology available, Resource Efficiency and Cleaner Production (RECP) will prove to be a future necessity for industry. To determine the perceived readiness towards a green economy contribution is thus of importance.
The study did a review on RECP, energy efficiency, supply of energy in South Africa, focus areas for energy efficiency and the benefits thereof. The study discussed energy efficiency incentive schemes and subsidisation funds available in South Africa. The study assessed the primary fields for RECP, the drivers and barriers to RECP and the willingness to participate in RECP initiatives in the Vaal Triangle. The study concluded that there exists a need in the Vaal Triangle for RECP initiatives and that there exists potential for the start of a green economy in the region. The research indicated the reaction towards RECP initiatives to be very positive in the studied region. / MBA, North-West University, Potchefstroom Campus, 2015
|
8 |
A needs assessment of the market for resource efficiency and cleaner production services in the Vaal Triangle / Theunis Christoffel BothaBotha, Theunis Christoffel January 2014 (has links)
Major energy-consuming countries implemented new laws on energy-efficiency during the course of 2013. The new energy-efficiency law make provision for a 16% reduction in energy intensity by 2015 in China. New law in the United States of America requires new fuel-economy standards. European Union law aims for a cut of 20% in energy demand for the countries forming part of the European Union. Japan, with the country's new energy strategy aims to decrease electricity demand with 10% by 2030 as stipulated in the new energy strategy.
South Arica is currently experiencing a shortage in electricity generating capacity and operates within its reserve margin. The construction of new power stations is in process to address the shortage but Eskom must finance these assets by increasing the electricity tariff. Electricity prices are predicted to double from 2013 to 2017. In addition to the tariff increases, the Energy Conservation Scheme (ECS) is also planned by Eskom whereby all electricity consumers have to reduce their electricity consumption by 10% or face penalties.
Energy efficiency initiatives in South Africa will help meet some of the country's social, economic, and environmental goals. These initiatives are important as they immediately tackle the problem of electricity shortages and are a cost-effective way of increasing available electricity supply.
The aim of this study was to determine the need for businesses in the Vaal Triangle to be resource efficient and practice clean production in order to be able to capitalise on that need. With the current knowledge and technology available, Resource Efficiency and Cleaner Production (RECP) will prove to be a future necessity for industry. To determine the perceived readiness towards a green economy contribution is thus of importance.
The study did a review on RECP, energy efficiency, supply of energy in South Africa, focus areas for energy efficiency and the benefits thereof. The study discussed energy efficiency incentive schemes and subsidisation funds available in South Africa. The study assessed the primary fields for RECP, the drivers and barriers to RECP and the willingness to participate in RECP initiatives in the Vaal Triangle. The study concluded that there exists a need in the Vaal Triangle for RECP initiatives and that there exists potential for the start of a green economy in the region. The research indicated the reaction towards RECP initiatives to be very positive in the studied region. / MBA, North-West University, Potchefstroom Campus, 2015
|
9 |
Proposta de diretrizes para integração entre a Produção Enxuta e Produção mais Limpa / Guidelines proposal for the integration between Lean Production and Cleaner ProductionCobra, Raphael Laraia Rocha de Barros 10 September 2015 (has links)
As operações industriais são objeto de muitas estratégias de gestão que visam melhorar o desempenho da empresa. Dentre estas estratégias podem ser encontradas a Produção Enxuta (Lean) e a Produção mais Limpa (P+L), implementadas de forma independente segundo objetivos distintos. Contudo, na prática, é frequente observar que as estratégias interagem dentro do contexto das indústrias, potencializando o ganho de desempenho operacional/ambiental ou prejudicando uma a outra quanto a seus objetivos. A academia vem recentemente evidenciando o possível relacionamento entre Lean e P+L dando principal atenção às interações positivas entre as estratégias, havendo poucos trabalhos que observam as interações negativas ou estudam os mecanismos pelos quais é possível descrever seu relacionamento. Como resposta a esta lacuna, esta pesquisa tem por objetivo principal propor diretrizes para a integração entre o Lean e P+L nas empresas. Esta proposta de diretrizes se baseia no levantamento do estado da arte da integração entre as estratégias, que fornece as informações sobre o seu relacionamento, que são, por sua vez, verificadas empiricamente. Para executar essa estratégia de pesquisa foi feita a aplicação de dois métodos científicos: a Revisão Bibliográfica Sistemática (RBS) e o estudo de caso. A RBS, desenvolvida para analisar o conhecimento disponível sobre a integração entre Lean e P+L, investigou 5 bases de dados científicas através das quais foram avaliados 380 estudos, que após a aplicação de filtros e adição de estudos citados por estudos selecionados foi possível chegar a 38 relevantes para a avaliação da integração entre Lean e P+L. A partir desses estudos, que reúnem desde artigos em periódicos e conferências até relatórios de agências governamentais, foi possível obter informações iniciais sobre o relacionamento entre o Lean e P+L, por exemplo os principais temas de convergência e divergência e o fenômeno compartilhado entre as teorias, definidos segundo a literatura. Para verificação empírica dessas informações, foram feitos estudos de caso em duas empresas brasileiras e duas empresas inglesas para observar a integração em contextos diferentes e setores diferentes. Os estudos mostraram que, de maneira geral, os departamentos ambientais, onde a P+L é praticada, e de Lean se encontram distantes. Dessa forma, nos casos não havia iniciativa de integração entre o Lean e a P+L, mas sim interações espontâneas que levavam a benefícios os prejuízos de uma ou outra estratégia. O conhecimento, primeiramente obtido na literatura e depois submetido a uma avaliação empírica, foi reunido em diretrizes de integração dentro dos temas de integração entre o Lean e a P+L: Objetivos, Custos, Desperdícios, Ciclo de Vida, Risco Ambiental, Impactos Ambientais, Práticas, Consumidor e Sociedade, Cultura, Recursos Humanos, Requisitos Legais e Cadeia de suprimentos. Estes resultados contribuem para que, ao invés de uma abordagem segregada entre as estratégias, a sustentabilidade possa ser inserida diretamente dentro dos sistemas produtivos. Desta forma, a integração entre o Lean e a P+L passa a ser tanto uma resposta à demanda do consumidor por melhor desempenho ambiental quanto uma alternativa para que as empresas aumentem a eficiência de seus processos. / Industrial operations are the subject of many management strategies aimed at improving the company\'s performance. Among these strategies are Lean Manufacturing (Lean) and Cleaner Production (CP), implemented independently according to different goals. However, in practice, it is often observed that the strategies interact within the industries´ context, increasing the operational/environmental performance improvements or harming each others´ goals. The academy has recently started emphasizing the possible relationship between Lean and CP giving primary attention to the positive interactions between strategies, having few studies observed negative interactions or studied the mechanisms through which it is possible to describe their relationship. In response to this gap this research´s main objective is to propose guidelines for the integration between Lean and CP in companies. This guidelines proposition is based on a study of the state of the art of the integration between the two strategies which provided information about their relationship, that was in turn verified empirically. To run this search strategy two scientific methods were applied, the Systematic Literature Review (SLR) and the case study. The RBS was performed to analyze the available knowledge about the integration between Lean and CP investigated 5 scientific databases in which 380 studies were evaluated. After applying filters and adding studies cited by the selected studies, 38 studies were reached, which were the most relevant to the evaluation of the integration between Lean and CP. These studies ranged from journal and conference articles to government agencies reports, and from them it was possible to obtain the initial information about the relationship between strategies such as their main themes and the shared phenomenon defined according to the literature. For empirical verification of this information, case studies were performed in two Brazilian companies and two English companies to observe the integration in different contexts and different sectors. The studies have shown that in general the environmental departments, where CP is practiced, and Lean are distant. Thus no integration initiative between Lean and CP was observed, but spontaneous interactions that led to randomly to convergences and divergences. The knowledge obtained first literature and then subjected to an empirical evaluation was gathered in integration guidelines displayed according to the integration themes between Lean and CP: Objectives, Cost, Waste, Life Cycle, Environmental Risk, Environmental Impacts, Practices, Consumer and Society, Culture, Human Resources, Legal Requirements and Supply Chain. These results contribute to, rather than maintaining a segregated approach between strategies, inserting sustainability directly into the production systems. Consequently, the integration between Lean and CP becomes both a response to consumer demand for a better environmental performance and an alternative for companies that want increase processes efficiency.
|
10 |
Avaliação clínica em estudo cruzado e randomizado de diferentes métodos para a redução da halitose matinal / Effect of different treatment methods for reducing morning bad breath. A randomized crossover clinical trial.Oliveira Neto, Jeronimo Manço de 01 October 2010 (has links)
O objetivo deste estudo foi de comparar a eficácia clínica de enxaguatórios bucais a higienizadores linguais e à escovação com dentifrício para higiene convencional, medidos por um monitor portátil de sulfetos BreathAlert™. Vinte voluntários saudáveis, com idade entre 18 e 50 anos (média de 35,9 anos), de ambos os gêneros, foram aleatoriamente alocados em um ensaio cruzado de cinco períodos. Foram testados: um higienizador de língua convencional (Kolbe®), um higienizador integrado à escova dental (Johnson´s Professional Extreme®), dois enxaguatórios bucais: 0,05% de cloreto de cetilpiridínio (Oral-B®) e 0,12% de digluconato de clorexidina (Periotherapy®- Bitufo) e uma escova dental (Johnson´s Professional Extreme®) com dentifrício fluoretado (Contente®) como controle positivo. Todos os voluntários foram orientados a permanecer por 20 horas sem qualquer tipo de higiene bucal, para registro dos índices iniciais de halitose. Cada produto foi utilizado uma vez seguido por uma semana de washout. O hálito foi mensurado antes (00), imediatamente após (0) e após 1, 2 e 3 horas do procedimento. Os produtos e os tempos foram comparados entre si pelo teste de Friedman (p<0,05) e, havendo diferenças significantes, foram analisados aos pares pelo teste de Wilcoxon, com ajuste de Bonferroni. Imediatamente após o uso dos produtos, somente o higienizador lingual acoplado à escova foi capaz de reduzir significantemente o hálito (p=0.0031) e seu efeito perdurou por até 2 horas. A clorexidina reduziu o hálito somente no final da segunda hora (p=0.004) e durou até três horas, enquanto que a higienização bucal com escova e dentifrício foi eficaz em reduzir o hálito já na primeira hora (p=0.002), perdurando por até 3 horas. Conclui-se que a higiene mecânica da língua foi capaz de reduzir imediatamente o hálito, porém com duração relativamente curta de seu efeito, enquanto que a clorexidina e a higienização da boca conseguiram reduzir o hálito por períodos maiores do que os observados na literatura que trabalha com halitose persistente. / The aim of this study was to compare the chemical effect of antimicrobial agents in mouthrinses and mechanical effect of tongue scrapers along with toothbrushing and dentifrice for conventional oral hygiene, measured by a handheld sulphide monitor BreathAlert™. Twenty healthy volunteers, from 18 to 50 years-old (the mean age was 35,9 years-old), of either gender, were randomly allocated into a five period cross-over trial. They were tested a conventional tongue scraper (Kolbe®), a tongue scraper coupled at the back of a toothbrushs head (Johnson′s Professional Extreme®), two mouthwashes: 0,05% cetylpyridinium chloride (Oral-B®) and 0,12% chlorhexidine digluconate (PerioTherapy®); and a soft-bristle toothbrush (Johnson′s Professional Extreme®) with fluoride toothpaste (Contente®) as a positive control. All the volunteers were asked to refrain from any kind of oral hygiene for a 20-hours period for baseline scores. Each product was used at once, followed by a one-week washout period. The breath was measured before (00), immediately after (0) and after 1, 2 and 3 hours after the procedure. A Friedman′s test (p <0.05) was used to compare the products and the times and, when significant differences were detected, a Wilcoxon′s test with Bonferroni correction was used (group to group). Immediately after the products use, only the toothbrush′s tongue scraper was able to significantly reduce the breath (p=0.0031) and its effect lasted for up to two hours. Chlorhexidine reduced the breath only at the final of the second hour (p=0.004) and lasted for three hours, while oral hygiene with toothbrush and toothpaste was effective in reducing the breath at the first hour (p=0.002) and lasted for up to three hours. It can be concluded that the mechanical cleaning of the tongue was able to immediately reduce the breath, but with relatively short duration of its effect, while chlorhexidine and the association of mechanical with chemical agents in oral hygiene can reduce the breath for longer periods than those observed in the literature which deals with chronic halitosis.
|
Page generated in 0.0427 seconds