22 research outputs found
Efetividade de escovas dentais de baixo custo, com ou sem o uso de dentifrício, na remoção da placa bacteriana em dentes decíduos
O principal objetivo deste estudo foi comparar a efetividade de uma escova dental de baixo custo (monobloco) à efetividade de uma escova convencional, com ou sem adição de dentifrício, em relação à remoção da placa dentária.Participaram deste estudo trinta e duas crianças de 4 a 6 anos de idade, que foram avaliadas sob quatro condições experimentais, definidas pela combinação de dois fatores: escova dental (convencional ou monobloco) e uso de dentifrício (com ou sem dentifrício). A efetividade dos tratamentos foi definida em termos de redução do índice de placa bacteriana, avaliado antes e após a escovação.Não foram encontradas diferenças estatisticamente significativas entre os dois tipos de escovas no que diz respeito à redução de placa bacteriana. Similarmente, não houve evidências estatísticas de que o uso de dentifrício aumenta o controle mecânico da placa. Esses resultados são importantes do ponto de vista de saúde pública, principalmente em países em desenvolvimento, onde a disseminação de técnicas educacionais e preventivas de baixo custo são fundamentais.The main objective of this study was to compare the effectiveness of a low cost toothbrush ("monoblock") to that of a conventional toothbrush with and without addition of dentifrice with respect to the removal of dental plaque. Thirty-two 4- to 6-year-old children took part in this study: they were evaluated under four experimental conditions defined by the combinations of the values of two factors, toothbrush (conventional or monoblock) and use of dentifrice (with or without). The effectiveness of the treatments was defined in terms of the reduction of a bacterial plaque index evaluated before and after toothbrushing. No statistically significant differences were detected between the two types of toothbrushes with respect to the reduction of the bacterial plaque index. Similarly, there were no statistical evidences that the use of dentifrice improves the mechanical control of dental plaque. These results are important from a public health point of view, specially in developing countries, where the dissemination of educational and preventive techniques of low cost are fundamental
Estudo da correlação dos índices de placa e gengival em mães e filhos
This study aimed to compare the periodontal condition between plaque and gingival indexes in 30 pairs of mother and child with mixed dentition, as well as to correlate the findings with some of their social and oral hygiene habits. Mother's and child's plaque and gingival indexes were recorded during clinical examination. Periapical and bitewing radiographs were taken in order to assess the presence of any pathologic bone loss. Questionnaires answered by the mothers were used to collect information regarding the mother's and the child's habits of tooth hygiene and the mother's job, instruction level and family income. The data collected from the mothers' group and from the children's group were statistically analyzed both separately and with the two groups together. From the statistical analyses (Pearson correlation test, student test and Covariance analysis), it was possible to conclude that there was a greater correlation between the plaque and gingival indexes in the mothers' group than in the children's group. No significant correlation between plaque and gingival indexes could be found between the pairs. Also, bone loss and plaque and gingival indexes in the children did not show any correlation. The mothers' plaque indexes increased with age and decreased when they flossed everyday and when they had a job. The children's plaque indexes were lower when they had their tooth hygiene done by their mothers, when the latter had declared that they flossed their children's teeth everyday, and also when the mothers had a job. Children's gingival indexes increased with age and decreased when they brushed their teeth more often, when their mothers had a job and when their mothers declared they are used to flossing every day.O objetivo deste estudo foi comparar a condição periodontal em 30 pares de mães e crianças com dentição mista, através dos índices de placa e gengival, bem como verificar sua correlação com alguns aspectos sociais e hábitos de higiene oral. No exame clínico foram registrados o índice de placa (IP) e índice gengival (IG) e, em seguida, foram realizadas tomadas radiográficas periapicais e interproximais que possibilitaram avaliar a possível presença de perdas ósseas em mães e crianças. Através de questionários, foram colhidas informações a respeito dos hábitos de higiene oral das mães e crianças, nível de escolaridade da mãe, se a mãe trabalhava fora e a renda familiar. Após análise estatística (Teste de Correlação de Pearson; test t de Student; Análise de Covariância), concluiu-se que houve maior correlação entre os índices de placa e gengival composto por adultos do que no grupo de crianças. Não foi encontrada correlação significante entre os índices de placa e gengival nos pares de mães e crianças. Não foi encontrada nenhuma correlação significante entre perda óssea e os índices de placa ou gengival dos pares. O índice de placa total das mães aumentou a idade e diminuiu quando a mãe utilizava fio dental diariamente e quando esta trabalhava fora. O índice gengival total das mães também foi reduzido quando elas trabalhavam fora. Houve redução no índice de placa total da criança quando a mãe a auxiliava durante a escovação, quando a mãe utilizava fio dental diariamente e quando esta trabalhava fora. O índice gengival total da criança foi maior com o aumento da idade e foi reduzido com aumento da sua freqüência de escovação, quando a mãe utilizava fio dental diariamente e quando a mãe trabalhava fora
Avaliação clínica de um cimento de ionômero de vidro utilizado como selante oclusal: a clinical evaluation
Since fluoride’s properties are widely known in the field of Preventive Dentistry, fluoride-releasing materials have been extensively investigated. Among the occlusal sealants, there is great expectation regarding the results that can be achieved with light-curing glass-ionomer cements due to their excellent properties. The aim of this study was to assess the use of one of these cements, Vitremer (3M) as an occlusal sealant. The material was applied using two different techniques; either associated or not with an adhesive system. After 6 and 12 months of observation, an evaluation was performed in 159 teeth to verify its retention as well as the presence of caries lesions. The technique that included the adhesive system showed better retention than the conventional one. Total retention was 84.9% for the experimental technique and 37.2% for the conventional technique after 12 months. There was no difference between bicuspids and molars regarding retention. Caries lesion was observed in a single tooth, for which a total loss of material was observed after one year.Sabendo-se do papel do flúor na Odontologia Preventiva, cada vez mais procuram-se materiais restauradores com propriedades de liberação deste íon. Dentre os selantes oclusais, grande expectativa existe em relação aos cimentos de ionômero de vidro, particularmente os fotopolimerizáveis, por possuírem melhores propriedades. O objetivo deste trabalho foi testar um destes cimentos, Vitremer (3M), aplicado em: combinação ou não com um adesivo. A avaliação foi realizada em 159 dentes, 6 e 12 meses após a aplicação do selante, observando-se sua retenção e a presença ou ausência de lesão de cárie. Concluiu-se que a técnica modificada, com adesivo, propiciou significativamente melhor retenção após 6 e 12 meses que a técnica convencional, não havendo diferença entre molares e pré-molares. Apenas um dente do grupo sem adesivo desenvolveu lesão de cárie após a perda do material
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4
While the increasing availability of global databases on ecological communities has advanced our knowledge
of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In
the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of
Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus
crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced
environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian
Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by
2050. This means that unless we take immediate action, we will not be able to establish their current status,
much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
Pervasive gaps in Amazonian ecological research
Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Use of chewing gum containing 15% of xylitol and reduction in mutans streptococci salivary levels
Frequent use of Xylitol may decrease the S. mutans levels. However, very little is known about whether this effect on the levels of cariogenic bacteria is maintained after the interruption of short-term usage of xylitol. This study aimed at evaluating changes in mutans streptococci (MS) salivary levels after using a chewing gum containing xylitol. Twelve volunteers harboring > 10(5) CFU MS/ml saliva levels were asked to chew Happydent-xylit® for 5 minutes, 5 X/day, for 30 days. Saliva samples were collected at baseline, at 30 days after xylitol usage began, and at 30 days beyond its interruption. MS salivary levels were estimated. The average salivary levels of MS in the ten subjects who completed the study were 13.17 (NL-CFU) at baseline (A). After the 30 days experimental period (B), this average decreased to 9.45 (NL-CFU). Nine of ten subjects studied showed a reduction in MS salivary levels in relation to baseline, whereas salivary levels were maintained in the remaining subject. At thirty days beyond the interruption of xylitol usage (C), the average levels of MS were still reduced to 10.31 (NL-CFU). Multiple sample comparison using the Bonferroni test revealed that the decrease in MS levels observed from baseline (A) to the time immediately after 30 days of xylitol usage (B) was statistically significant (p < 0.05), and those levels were still decreased between baseline and 30 days beyond the interruption of xylitol usage (C). So, the use of xylitol induced a reduction in MS salivary levels after a short period of usage which persisted beyond its interruption
Efficacy of 1.23% APF gel applications on incipient carious lesions: a double-blind randomized clinical trial
The aim of this double-blind randomized clinical trial was to evaluate the efficacy of 1.23% APF gel application on the arrest of active incipient carious lesions in children. Sixty 7- to 12-year-old children, with active incipient lesions were included in the study. Children were divided randomly into 2 groups: 1.23% APF gel and placebo gel applications. Each group received 8 weekly applications of treatment. The lesions were re-evaluated at the 4th and 8th appointments. Poisson regression analysis was used to estimate relative risks of the presence of active white spot lesions. Groups showed similar results (PR = 1.67; CI 95% 0.69–3.98). The persistence of at least 1 active lesion was associated with a higher number of lesions in the baseline (PR = 2.67; CI 95% 1.19–6.03), but not with sugar intake (PR = 1.06; CI 95% 0.56–2.86) and previous exposure to fluoride dentifrice (PR = 1.26; CI 95% 0.49–2.29). The trial demonstrates the equivalence of the treatments. The use of the APF gel showed no additional benefits in this sample of children exposed to fluoridated water and dentifrice. The professional dental plaque removal in both groups may also account for the resulting equivalence of the treatments