Características clínicas de reanimações cardiopulmonares intra-hospitalares registradas em prontuário: estudo transversal / Clinical characteristics of in-hospital cardiopulmonary resuscitations recorded in medical records: a cross-sectional study / Características clínicas de las reanimaciones cardiopulmonares intrahospitalarias registradas en las historias clínicas: estudio transversal

Objetivo: identificar características clínicas das paradas cardiopulmonares e reanimações cardiopulmonares ocorridas em ambiente intra-hospitalar. Método: estudo quantitativo, prospectivo e observacional, a partir de informações de prontuários de pacientes submetidos a manobras de reanimação devido à parada cardiopulmonar entre janeiro e dezembro de 2021. Utilizou-se um instrumento baseado nas variáveis do modelo de registro Utstein. Resultados: em 12 meses foram registradas 37 paradas cardiopulmonares. A maioria ocorreu na unidade de terapia intensiva respiratória, com causa clínica mais prevalente hipóxia. 65% dos pacientes foram intubados no atendimento e 57% apresentaram ritmo atividade elétrica sem pulso. A duração da reanimação variou entre menos de cinco a mais de 20 minutos. Como desfecho imediato, 57% sobreviveram. Conclusão: dentre os registros analisados, a maior ocorrência de paradas cardiopulmonares foi na unidade de terapia intensiva respiratória, relacionada à Covid-19. Foram encontrados registros incompletos e ausência de padronização nas condutas.

Objective: identify the clinical characteristics of cardiopulmonary arrests and cardiopulmonary resuscitations in the in-hospital environment. Method: this is a quantitative, prospective and observational study based on information from the medical records of patients who underwent resuscitation maneuvers due to cardiopulmonary arrest between January and December 2021. An instrument based on the variables of the Utstein registration protocol was used. Results: thirty-seven cardiopulmonary arrests were recorded in 12 months. The majority occurred in a respiratory intensive care unit, with hypoxia being the most prevalent clinical cause. Sixty-five percent of the patients were intubated and 57% had pulseless electrical activity. The duration of resuscitation ranged from less than five to more than 20 min. As for the immediate outcome, 57% survived. Conclusion: among the records analyzed, the highest occurrence of cardiopulmonary arrests was in respiratory intensive care units, and they were related to Covid-19. Moreover, incomplete records and a lack of standardization in cardiopulmonary resuscitation procedures were found.

Objetivo: Identificar las características clínicas de paros cardiopulmonares y reanimaciones cardiopulmonares que ocurren en un ambiente hospitalario. Método: estudio cuantitativo, prospectivo y observacional, realizado a partir de información presente en historias clínicas de pacientes sometidos a maniobras de reanimación por paro cardiorrespiratorio entre enero y diciembre de 2021. Se utilizó un instrumento basado en las variables del modelo de registro Utstein. Resultados: en 12 meses se registraron 37 paros cardiopulmonares. La mayoría ocurrió en la unidad de cuidados intensivos respiratorios, la causa clínica más prevalente fue la hipoxia. El 65% de los pacientes fue intubado durante la atención y el 57% presentaba un ritmo de actividad eléctrica sin pulso. La duración de la reanimación varió entre menos de cinco y más de 20 minutos. Como resultado inmediato, el 57% sobrevivió. Conclusión: entre los registros analizados, la mayor cantidad de paros cardiopulmonares se dio en la unidad de cuidados intensivos respiratorios, relacionada con Covid-19. Se encontraron registros incompletos y falta de estandarización en el procedimiento.

Case report of dental intervention in intensive care unit in patient with face burns / Relato de caso de intervenção odontológica em unidade de terapia intensiva em paciente com queimadura de face

ABSTRACT Burns are identified as a trauma that has a high degree of mortality and disability, both functionally and aesthetically. In the head and neck region, burn injuries can evolve mainly due to hypertrophic scars and contractures This study aimed to observe the progression and outcome of healing in face burns with the use of a low-power laser and oral splint. A descriptive and observational study was carried out, which corresponds to the case report of a severely burned patient with burns in the orofacial region. Early odontologic treatment care during hospitalization is essential to reduce hypertrophic scars and contractures in a severely burned patient with burns in the orofacial region.

RESUMO As queimaduras são identificadas como um trauma que possui alto grau de mortalidade e incapacidade, tanto no aspecto funcional quanto na estética. Em região de cabeça e pescoço, as lesões por queimadura podem evoluir principalmente com cicatrizes hipertróficas e contraturas. O Objetivo foi avaliar a progressão e o desfecho do reparo tecidual em queimadura de face com o uso do laser de baixa potência e splint oral. Trata-se de um estudo observacional descritivo, que corresponde ao relato de caso de um paciente grande queimado. A intervenção odontológica é fundamental para que se diminua cicatrizes hipertróficas e contraturas, restabelecendo da melhor forma possível a função do sistema estomatognático.

Impact of motion correction on [18F]-MK6240 tau PET imaging.

Objective. Positron emission tomography (PET) imaging of tau deposition using [18F]-MK6240 often involves long acquisitions in older subjects, many of whom exhibit dementia symptoms. The resulting unavoidable head motion can greatly degrade image quality. Motion increases the variability of PET quantitation for longitudinal studies across subjects, resulting in larger sample sizes in clinical trials of Alzheimer's disease (AD) treatment.Approach. After using an ultra-short frame-by-frame motion detection method based on the list-mode data, we applied an event-by-event list-mode reconstruction to generate the motion-corrected images from 139 scans acquired in 65 subjects. This approach was initially validated in two phantoms experiments against optical tracking data. We developed a motion metric based on the average voxel displacement in the brain to quantify the level of motion in each scan and consequently evaluate the effect of motion correction on images from studies with substantial motion. We estimated the rate of tau accumulation in longitudinal studies (51 subjects) by calculating the difference in the ratio of standard uptake values in key brain regions for AD. We compared the regions' standard deviations across subjects from motion and non-motion-corrected images.Main results. Individually, 14% of the scans exhibited notable motion quantified by the proposed motion metric, affecting 48% of the longitudinal datasets with three time points and 25% of all subjects. Motion correction decreased the blurring in images from scans with notable motion and improved the accuracy in quantitative measures. Motion correction reduced the standard deviation of the rate of tau accumulation by -49%, -24%, -18%, and -16% in the entorhinal, inferior temporal, precuneus, and amygdala regions, respectively.Significance. The list-mode-based motion correction method is capable of correcting both fast and slow motion during brain PET scans. It leads to improved brain PET quantitation, which is crucial for imaging AD.

Comparing and linking machine learning and semi-mechanistic models for the predictability of endemic measles dynamics.

Measles is one the best-documented and most-mechanistically-studied non-linear infectious disease dynamical systems. However, systematic investigation into the comparative performance of traditional mechanistic models and machine learning approaches in forecasting the transmission dynamics of this pathogen are still rare. Here, we compare one of the most widely used semi-mechanistic models for measles (TSIR) with a commonly used machine learning approach (LASSO), comparing performance and limits in predicting short to long term outbreak trajectories and seasonality for both regular and less regular measles outbreaks in England and Wales (E&W) and the United States. First, our results indicate that the proposed LASSO model can efficiently use data from multiple major cities and achieve similar short-to-medium term forecasting performance to semi-mechanistic models for E&W epidemics. Second, interestingly, the LASSO model also captures annual to biennial bifurcation of measles epidemics in E&W caused by susceptible response to the late 1940s baby boom. LASSO may also outperform TSIR for predicting less-regular dynamics such as those observed in major cities in US between 1932-45. Although both approaches capture short-term forecasts, accuracy suffers for both methods as we attempt longer-term predictions in highly irregular, post-vaccination outbreaks in E&W. Finally, we illustrate that the LASSO model can both qualitatively and quantitatively reconstruct mechanistic assumptions, notably susceptible dynamics, in the TSIR model. Our results characterize the limits of predictability of infectious disease dynamics for strongly immunizing pathogens with both mechanistic and machine learning models, and identify connections between these two approaches.

Reorganization of nursing work in an intensive care unit during the COVID-19 pandemic.

OBJECTIVE: To describe the reorganization of nursing work in an intensive care unit of a public hospital due to the COVID-19 pandemic. METHOD: Report of the experience from February to April 2020, about the reorganization of a unit. RESULTS: The description of the experience was divided into four moments: Definition of the cohort isolation; Reorganization of the intensive care units as General and Respiratory; Health care teams and work shifts; and Wearing and removing protective clothing by the teams. CONCLUSION: The COVID -19 pandemic brought numerous challenges to the management of intensive care units. The socialization of management experiences can contribute to the definition of new strategies, including in the post-pandemic period.

Cerebellar atrophy and its implications on gait in cerebral amyloid angiopathy.

OBJECTIVE: Recent data suggest that cerebral amyloid angiopathy (CAA) causes haemorrhagic lesions in cerebellar cortex as well as subcortical cerebral atrophy. However, the potential effect of CAA on cerebellar tissue loss and its clinical implications have not been investigated. METHODS: Our study included 70 non-demented patients with probable CAA, 70 age-matched healthy controls (HCs) and 70 age-matched patients with Alzheimer's disease (AD). The cerebellum was segmented into percent of cerebellar subcortical volume (pCbll-ScV) and percent of cerebellar cortical volume (pCbll-CV) represented as percent (p) of estimated total intracranial volume. We compared pCbll-ScV and pCbll-CV between patients with CAA, HCs and those with AD. Gait velocity (metres/second) was used to investigate gait function in patients with CAA. RESULTS: Patients with CAA had significantly lower pCbll-ScV compared with both HC (1.49±0.1 vs 1.73±0.2, p<0.001) and AD (1.49±0.1 vs 1.66±0.24, p<0.001) and lower pCbll-CV compared with HCs (6.03±0.5 vs 6.23±0.6, p=0.028). Diagnosis of CAA was independently associated with lower pCbll-ScV compared with HCs (p<0.001) and patients with AD (p<0.001) in separate linear regression models adjusted for age, sex and presence of hypertension. Lower pCbll-ScV was independently associated with worse gait velocity (ß=0.736, 95% CI 0.28 to 1.19, p=0.002) in a stepwise linear regression analysis including pCbll-CV along with other relevant variables. INTERPRETATION: Patients with CAA show more subcortical cerebellar atrophy than HC or patients with AD and more cortical cerebellar atrophy than HCs. Reduced pCbll-ScV correlated with lower gait velocity in regression models including other relevant variables. Overall, this study suggests that CAA causes cerebellar injury, which might contribute to gait disturbance.

Exploring Risk Factors in Suicidal Ideation and Attempt Concept Cooccurrence Networks.

Suicide is a significant and rising threat to public health. In the United States, 47,500 people died from suicide in 2019, a 10-year increase of 30%. Many researchers are interested in studying the risk factors associated with suicidal ideation and suicide attempt to help inform clinical screening, intervention, and prevention efforts. Many suicide risk factor analyses draw from clinical subdomains and quantify risk factors independently. While traditional modeling approaches might assume independence between risk factors, current suicide research suggests that the development of suicidal intent is a complex, multifactorial process. Thus, it may be beneficial to how suicide risk-factors interact with one another. In this study, we used network analysis to generate visual suicidality risk relationship diagrams. We extract medical concepts from free-text clinical notes and generate cooccurrence-based risk networks for suicidal ideation and suicide attempt. In addition, we generate a network of risk factors for suicidal ideation which evolves into a suicide attempt. Our networks were able to replicate existing risk factor findings and provide additional insight into the degree to which risk factors behave as independent morbidities or as interacting comorbidities with other risk factors. These results highlight potential avenues for risk factor analyses of complex outcomes using network analysis.

Reorganization of nursing work in an intensive care unit during the COVID-19 pandemic / Reorganización del trabajo de enfermería en una unidad de atención intensiva durante la pandemia COVID-19 / Reorganização do trabalho da enfermagem em uma unidade de terapia intensiva durante a pandemia de Covid-19

ABSTRACT Objective: To describe the reorganization of nursing work in an intensive care unit of a public hospital due to the COVID-19 pandemic. Method: Report of the experience from February to April 2020, about the reorganization of a unit. Results: The description of the experience was divided into four moments: Definition of the cohort isolation; Reorganization of the intensive care units as General and Respiratory; Health care teams and work shifts; and Wearing and removing protective clothing by the teams. Conclusion: The COVID -19 pandemic brought numerous challenges to the management of intensive care units. The socialization of management experiences can contribute to the definition of new strategies, including in the post-pandemic period.

RESUMEN Objetivo: Describir la reorganización del trabajo de enfermería en una unidad de cuidados intensivos de un hospital público debida a la pandemia de COVID-19. Método: Relato de la experiencia que ocurrió de febrero a abril de 2020, sobre la reorganización de una unidad. Resultados: La descripción de la experiencia se dividió en cuatro momentos: Definición del aislamiento por cohorte, Reorganización de las unidades de cuidados intensivos en general y respiratoria, Equipos de asistencia y horarios de servicio, y Poner y remover el EPP. Conclusión: La pandemia de COVID-19 trajo numerosos desafíos al manejo de las unidades de cuidados intensivos. Compartir las experiencias de gestión puede contribuir a la definición de nuevas estrategias, incluso en el período posterior a la pandemia.

RESUMO Objetivo: Descrever a reorganização do trabalho da enfermagem de uma unidade de terapia intensiva de um hospital público em função da pandemia de Covid-19. Método: Relato da experiência vivenciada no período de fevereiro a abril de 2020, acerca da reorganização de uma unidade. Resultados: A descrição da experiência está dividida em quatro momentos: Definição do isolamento por coorte, Reorganização das unidades de terapia intensiva em Geral e Respiratória, Equipes assistenciais e escalas de serviço e Paramentação e desparamentação das equipes. Conclusão: A pandemia de Covid-19 trouxe inúmeros desafios para a gestão das unidades de terapia intensiva. Socializar as experiências de gestão pode contribuir para a definição de novas estratégias, inclusive no período pós-pandemia.

Elementos facilitadores no processo de doação de órgãos na perspectiva dos profissionais / Facilitating elements in the organ donation process from the perspective of professionals

Objetivou identificar os elementos facilitadores no processo de doação de órgãos e tecidos para transplante, na perspectiva dos profissionais das Comissões Hospitalares de Transplantes. Estudo descritivo, qualitativo, realizado com 20 profissionais que compõem as Comissões Intra-Hospitalares de Doação de Órgãos e Tecidos para Transplante. A coleta de dados ocorreu por meio de entrevista semiestruturada, analisados por meio da técnica do Discurso do Sujeito Coletivo. Emergiram três ideias centrais que versaram sobre os profissionais atuantes na Terapia Intensiva e Emergência como membros da Comissão Hospitalar de Transplantes; Suporte da Central Estadual de Transplante; Coordenação da Comissão Hospitalar de Transplantes. Identificou-se como elementos facilitadores no processo de doação de órgãos e tecidos os profissionais das comissões do quadro funcional das respectivas unidades envolvidas no processo. É necessário um serviço organizado e articulado, de profissionais capacitados e de liderança resolutiva para garantir sucesso no processo de doação de órgãos e tecidos para transplantes.

This work has aimed to identify the facilitating elements in the organ and tissue donation process for transplantation from the perspective of professionals from Brazilian Hospital Transplantation Commissions. This is a descriptive, qualitative study conducted with twenty professionals who make up the In-Hospital Commissions for Organ and Tissue Donation for Transplantation. Data collection took place through semi-structured interviews analyzed using the Collective Subject Discourse technique. Three central ideas have emerged, which address the professionals working in Intensive Care and Emergency as members of the Hospital Transplantation Commission (CHT), the Support from the State Transplant Center (CET), and the Coordination of the Hospital Transplantation Commission. The facilitating elements of the organ and tissue donation process were the professionals of the commissions from the respective units involved in the process. An organized and articulated service, with trained professionals and resolute leadership, is necessary to ensure the success in the organ and tissue donation process for transplantation.

In Vivo Tau, Amyloid, and Gray Matter Profiles in the Aging Brain.

UNLABELLED: We provide a comparative in vivo examination of the brain network-based distribution of two hallmarks of Alzheimer's disease (AD) pathology in cognitively normal individuals: (1) Tau, detected with a novel positron emission tomography (PET) tracer known as (18)F-AV-1451; and (2) amyloid-ß, quantified with (11)C-PiB PET. We used a high-resolution graph-based approach to investigate local-to-local and local-to-distributed cortical associations between the maps of Tau, amyloid-ß, and gray matter intensity. Our study shows that Tau and amyloid-ß deposits are associated with distinctive spatial patterns of brain tissue loss. Moreover, Tau and amyloid-ß accumulations have strong network interdigitations in heteromodal and associative areas of the cortical mantle, particularly the inferior-lateral temporal lobe. These findings contribute significantly to our understanding of how these two main hallmarks of AD pathology propagate across the elderly human brain. SIGNIFICANCE STATEMENT: It has been postulated that Alzheimer's disease (AD) pathology interacts and resides within system-level circuits of the human brain, long before the onset of cognitive symptoms. However, a side-by-side comparison of tissue loss, amyloid-ß, and Tau deposition in early stages of the disease has been precluded until the recent advent of Tau tracer-based neuroimaging. In this study, we used Tau positron emission tomography and network analyses to disentangle these pathological relationships. We found that Tau and amyloid-ß deposits are associated with distinctive spatial patterns of brain tissue loss. Moreover, we uncovered the network interdigitations of Tau and amyloid-ß in the cortical mantle. These findings contribute significantly to our understanding of how two main hallmarks of AD pathology propagate across the elderly human brain.

In vivo characterization of the early states of the amyloid-beta network.

Alzheimer's disease is a neurodegenerative disease that is associated with the abnormal accumulation of amyloid-ß. Much is known about regional brain atrophy in Alzheimer's disease, yet our knowledge about the network nature of Alzheimer's disease-associated amyloid-ß accumulation is limited. We use stepwise connectivity analysis of Pittsburgh Compound B positron emission tomography images to reveal the network properties of amyloid-ß deposits in normal elderly subjects and clinical patients with Alzheimer's disease. We found that amyloid-ß accumulation in the medial temporal lobe is associated with accumulation in cortical regions such as orbitofrontal, lateral temporal and precuneus/posterior cingulate cortices in Alzheimer's disease. In normal subjects, there was a predominant association between amyloid-ß deposits in the hippocampus and the midline prefrontal/orbitofrontal regions, even in those with very low amyloid-ß burden. Moreover, the orbitofrontal cortex, amygdala nucleus and hippocampus exhibit hub properties in the amyloid-ß network that may be critical to understanding the putative spreading mechanisms of Alzheimer's disease pathology in early stages.

Cerebral amyloid angiopathy burden associated with leukoaraiosis: a positron emission tomography/magnetic resonance imaging study.

OBJECTIVE: We hypothesized that vascular amyloid contributes to chronic brain ischemia, therefore amyloid burden measured by Pittsburgh compound B retention on positron emission tomography (PiB PET) would correlate with the extent of magnetic resonance imaging (MRI) white matter hyperintensities (WMH; or leukoaraiosis) in patients with high vascular amyloid deposition (cerebral amyloid angiopathy [CAA]) but not in patients with high parenchymal amyloid deposition (Alzheimer disease [AD]; mild cognitive impairment [MCI]) or in healthy elderly (HE) subjects. METHODS: Forty-two nondemented CAA patients, 50 HE subjects, and 43 AD/MCI patients had brain MRI and PiB PET. Multivariate linear regression was used to assess the independent association between PiB retention and white matter disease volume, controlling for age, gender, apolipoprotein E genotype, and vascular risk factors within each group. RESULTS: CAA patients were younger than HE and AD subjects (68 ± 10 vs 73.3 ± 7 and 74 ± 7.4, p < 0.01) but had higher amounts of WMH (median = 21 vs 3.2 and 10.8 ml, respectively, p < 0.05 for both comparisons). Global PiB retention and WMH showed strong correlation (rho = 0.52, p < 0.001) in the CAA group but not in HE or AD. These associations did not change in the multivariate models. Lobar microbleed count, another marker of CAA severity, also remained as an independent predictor of WMH volume. INTERPRETATION: Our results indicate that amyloid burden in CAA subjects (with primarily vascular amyloid) but not AD subjects (with primarily parenchymal amyloid) independently correlates with WMH volume. These findings support the idea that vascular amyloid burden directly contributes to chronic cerebral ischemia and highlights the possible utility of amyloid imaging as a marker of CAA severity.

Predicting sites of new hemorrhage with amyloid imaging in cerebral amyloid angiopathy.

OBJECTIVE: We aimed to determine whether amyloid imaging can help predict the location and number of future hemorrhages in cerebral amyloid angiopathy (CAA). METHODS: We performed a longitudinal cohort study of 11 patients with CAA without dementia who underwent serial brain MRIs after baseline amyloid imaging with Pittsburgh compound B (PiB). Mean distribution volume ratio (DVR) of PiB was determined at the sites of new micro/macrobleeds identified on follow-up MRI and compared with PiB retention at "simulated" hemorrhages, randomly placed in the same subjects using a probability distribution map of CAA-hemorrhage location. Mean PiB retention at the sites of observed new bleeds was also compared to that in shells concentrically surrounding the bleeds. Finally the association between number of incident bleeds and 3 regional amyloid measures were obtained. RESULTS: Nine of 11 subjects had at least one new microbleed on follow-up MRI (median 4, interquartile range [IQR] 1-9) and 2 had 5 new intracerebral hemorrhages. Mean DVR was greater at the sites of incident bleeds (1.34, 95% confidence interval [CI] 1.23-1.46) than simulated lesions (1.14, 95% CI 1.07-1.22, p < 0.0001) in multivariable models. PiB retention decreased with increasing distance from sites of observed bleeds (p < 0.0001). Mean DVR in a superior frontal/parasagittal region of interest correlated independently with number of future hemorrhages after adjustment for relevant covariates (p = 0.003). CONCLUSIONS: Our results provide direct evidence that new CAA-related hemorrhages occur preferentially at sites of increased amyloid deposition and suggest that PiB-PET imaging may be a useful tool in prediction of incident hemorrhages in patients with CAA.

The effect of argon and nitrogen ion implantation on nickel-titanium rotary instruments.

INTRODUCTION: This qualitative study investigated the effect of N(2)(+) and Ar(+) ion implantation on morphologic alterations and fatigue resistance in Pro Taper S1 NiTi (Dentsply-Maillefer, Ballaigues, Switzerland) rotary instruments. METHODS: Instruments were divided into three groups: N(2)(+) implanted, Ar(+) implanted, and unmodified control group. All instruments were used to prepare five curved canals in epoxy resin blocks with brushing motion. The instruments were examined in a scanning electron microscope (SEM) before use, after first use, and after the fifth use. A more demanding cyclic fatigue test was undertaken, submitting the instruments to 15-second periods of continuous rotation inside the curved canals without a brushing motion. Crack formation was analyzed with the SEM, and the number of 15-second periods required to fracture each instrument was recorded. RESULTS: No significant morphologic alterations were observed in the instruments after the preparation of five canals. Crack density was similar in all groups. In the subsequent cyclic fatigue test, instruments implanted with nitrogen performed worse than those implanted with argon and the control group. Fracture faces show differences in the fracture modes. CONCLUSIONS: Ar(+) implantation improved the performance of S1 files moderately, whereas nitrogen ion-implanted files performed worse in the fatigue test. A reduction in file performance seems to be caused by nitrogen diffusion in the grain boundaries, instead of the desired improvement caused by titanium nitride formation.

Efeito da esterilização sobre a eficiência de corte dos instrumentos endodônticos ProTaper® e K3® / Effect of the sterilization on the cutting efficiency of ProTaper® and K3® endodontic instruments

Objetivo: Avaliar o efeito da esterilização sobre a eficiência de corte dos instrumentos endodônticos rotatórios, ProTaper® (Dentsply Maillefer Instruments S.A., Ballaigues, Suíça) e K3® (Sybron/Kerr, Orange, CA, USA), através do método tempo X pesagem. Método: Para isso, foram utilizados 60 canais simulados e 66 instrumentos, sendo 36 do sistema ProTaper® (Dentsply Maillefer Instruments S.A., Ballaigues, Suíça) e 30 do sistema K3 (Sybron/Kerr, Orange, CA, USA). Os instrumentos rotatórios foram divididos em quatro grupos experimentais. Nos instrumentos do grupo A (K3®, Sybron/Kerr, Orange, CA, USA) e do grupo B (ProTaper®, Dentsply Maillefer Instruments S.A., Ballaigues, Suíça), foi realizado o processo de limpeza e esterilização. Já nos instrumentos do grupo C (K3®, Sybron/Kerr, Orange, CA, USA) e do grupo D (ProTaper®, Dentsply Maillefer Instruments S.A., Ballaigues, Suíça), foi realizado apenas o processo de limpeza, não sendo esterilizados. Resultados: Quanto à análise dos resultados, foi utilizado o teste t-Student, através do qual se pôde verificar que os instrumentos do grupo A tiveram uma maior eficiência de corte em relação aos do grupo B, da mesma forma que os instrumentos do grupo C em relação aos do grupo D, embora não tenha ocorrido diferença estatística significativa. Além disso, em relação ao número de usos, também não houve diferença estatística entre os grupos experimentais, porém em todos os grupos houve um decréscimo na eficiência de corte com o decorrer dos usos. Conclusão: Assim, a capacidade de corte dos instrumentos endodônticos rotatórios ProTaper® (Dentsply Maillefer Instruments S.A., Ballaigues, Suíça) e K3® (Sybron/Kerr, Orange, CA, USA) não foi afetada estatisticamente após o emprego de seis ciclos de esterilizações em autoclave.

Objective: This objective of this study was to evaluate the effect of sterilization on the cutting efficiency of rotary endodontic instruments, ProTaper® (Dentsply Maillefer Instruments S.A., Ballaigues, Suíça) and K3® (Sybron/Kerr, Orange, CA, USA), by the time X weighing method.Method: For this purpose, 60 simulated canals and 66 instruments were used (36 of the ProTaper® system, (Dentsply Maillefer Instruments S.A., Ballaigues, Switzerland) and 30 of the K3® system (Sybron/Kerr, Orange, CA, USA). The rotary instruments were divided into four experimental groups. The instruments in Group A (K3®, Sybron/Kerr, Orange, CA, USA) and Group B (ProTaper®, Dentsply Maillefer Instruments S.A., Ballaigues, Switzerland), were subjected to a process of cleaning and sterilization. Whereas the instruments in Group C (K3®, Sybron/Kerr, Orange, CA, USA) and Group D (ProTaper®, Dentsply Maillefer Instruments S.A., Ballaigues, Switzerland), were subjected to the cleanness process only, and were not sterilized. Results: As regards analysis of the results, the Student's-t test was used, by which it was verified that the instruments in Group had greater cutting efficiency in comparison with those in Group B. Similarly the instruments in Group C had greater cutting efficiency in comparison with those in Group D, nevertheless, there was no statistically significant difference. Moreover, as regards the number times of use, there was also no statistically significant difference between the experimental groups. However in all the groups there was a decrease in the cutting efficiency with an increasing number of times of use. Conclusion: Thus, the cutting efficiency of rotary endodontic instruments K3® (Sybron/Kerr, Orange, CA, USA) and ProTaper® (Dentsply Maillefer Instruments S.A., Ballaigues, Suição) was not statistically affected after the use of 6 autoclave sterilization cycles.

Aplicação do laser na terapia endodôntica / Application of the laser in the endodontic therapy

Este trabalho consiste numa revisão de literatura sobre a utilização do laser durante arealização do tratamento endodôntico. Neste artigo, mostraremos algumas etapas da terapia endodôntica em que esses aparelhos podem ser utilizados, suas influências nas estruturas dentárias e as suas contra-indicações.

This work consists in a literature review on the use of the laser during the accomplishment ofthe endodontics treatment. In this article, we will show someone stages of the endodontics therapy where if they use these devices, it’s influences in the dental structures and it’s against indications.

Análise da concentração e do pH de diferentes soluções de hipoclorito de sódio encontradas no mercado / Analysis of the concentration and pH of different solutions of sodium hypochlorite found in the market

Verificou-se o teor de cloro ativo e o pH de 11 soluções de hipoclorito de sódio de diferentes marcas e concentrações existentes no mercado. Nove destas soluções foram adquiridas em casas dentárias da cidadede Porto Alegre/RS e duas na Farmácia Escola da ULBRA – campus Canoas/RS. O teor de cloro ativo foiverificado através da titulação iodométrica, e o pH, através de um aparelho denominado peagâmetro. Osvalores encontrados foram anotados e comparados aos valores existentes nos rótulos dos produtos e tam-bém com valores considerados ideais pela literatura consultada. Pode-se verificar que das 11 soluções de hipoclorito de sódio analisadas, apenas 5 apresentaram valores da concentração quimicamente aceitáveispara uso; os valores do pH mostraram-se adequados para todas as soluções analisadas.

One verified the active chlorine content and pH of 11 solutions of sodium hypochlorite of different marks and concentrations existing in the market. Nine of these solutions had been acquired in dental houses of the city of Porto Alegre/RS and two in the Pharmacy School of the ULBRA – Canoas/RS. Theactive chlorine content was verified through the titrimetry and pH through a called device pH-metro.The found values had been written and compared with the values existing in the labels of the product sand with values also considered ideal for consulted literature. It can be verified that of the 11 solutionsof sodium hypochlorite analyzed, only 5 had presented acceptable values of the concentration for use; the values of pH had revealed adequate for all the analyzed solutions.

Influência da esterilização e da solução de hipoclorito de sódio nas propriedades dos instrumentos endodônticos / Influence of sterilization and sodium hypochlorite solution in properties of endodontics instruments

Este artigo visa discutir, baseado em uma revisão de literatura, a influência da esterilização e dasolução de hipoclorito de sódio sobre as propriedades dos instrumentos endodônticos. Pode-se verificarque não houve alterações significativas nas propriedades dos instrumentos endodônticos quando subme-tidos a vários ciclos de esterilização e ao contato com a solução de hipoclorito de sódio.

This paper aims to discuss by means of a literature review, influence of sterilization and sodium hypochlorite solution in properties of endodontics instruments. Can be verified that didn’t have significant alterations in properties of endodontics instruments when submitted to some cycles of sterilization and sodium hypochlorite solution.

Utilização e forma de armazenamento da solução de hipoclorito de sódio por cirurgiões-dentistas / Use and form of storage of the sodium hypochlorite solution by dentists

O propósito deste estudo foi verificar a utilização e a forma de armazenamento da solução dehipoclorito de sódio empregada durante o preparo químico mecânico de canais radiculares por cirurgi-ões dentistas. Um questionário foi preparado e entregue pessoalmente para cada participante, totalizando350 entrevistas. Somente participaram da pesquisa cirurgiões dentistas formados que realizavam trata-mento endodôntico. Verificou-se que 99,42% dos profissionais entrevistados utilizam a solução dehipoclorito de sódio para irrigação de canais radiculares, sendo que a concentração mais utilizada foide 1%. Observou-se, também, que a solução é adquirida pela maioria dos profissionais em casas dentárias,mantida em plástico branco e à temperatura ambiente. Devido à alta instabilidade da solução dehipoclorito de sódio, cabe aos cirurgiões dentistas conscientizarem-se da correta forma de armazenamento,o que pode minimizar a perda de cloro livre e aumentar a eficácia da solução.

The aim of this study was verify the utilization and form of storage of sodium hypochloritesolution employed during mechanical chemical preparation of root canals by dentists. A questionnaire was prepared and individually delivered to each professional, totaling 350 interviews. Only participatedof the research dentists graduated which realized endodontic treatment. Was verified that 99,42% ofinterviewed professionals use sodium hypochlorite solution for irrigation of root canals, being that theconcentration more used was 1%. Was also observed that solution is acquired by the majority of theprofessionals in dental houses, kept in white plastic bottles and in ambient temperature. Due highinstability of the sodium hypochlorite solutions, fits to the dentists to be acquired knowledge of thecorrect form of storage of the sodium hypochlorite solutions, what can minimize the loss of free chlorineto increase the effectiveness of the solution.