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Background.Anecdotal reports are appearing in the scientific literature about cases of brain tumors in interventional physicians who are exposed to ionizing radiation. In response to this alarm, several designs of leaded caps have been made commercially available. However, the results reported on their efficacy are discordant.Objective.To synthesize, by means of a systematic review of the literature, the capacity of decreasing radiation levels conferred by radiation attenuating devices (RADs) at the cerebral level of interventional physicians.Methodology.A systematic review was performed including the following databases: MEDLINE, SCOPUS, EBSCO, Science Direct, Cochrane Controlled Trials Register (CENTRAL), WOS, WHO International Clinical Trials Register, Scielo and Google Scholar, considering original studies that evaluated the efficacy of RAD in experimental or clinical contexts from January 1990 to May 2023. Data selection and extraction were performed in triplicate, with a fourth author resolving discrepancies.Results.Twenty articles were included in the review from a total of 373 studies initially selected from the databases. From these, twelve studies were performed under clinical conditions encompassing 3801 fluoroscopically guided procedures, ten studies were performed under experimental conditions with phantoms, with a total of 88 procedures, four studies were performed using numerical calculations with a total of 63 procedures. The attenuation and effectiveness of provided by the caps analyzed in the present review varying from 12.3% to 99.9%, and 4.9% to 91% respectively.Conclusion.RAD were found to potentially provide radiation protection, but a high heterogeneity in the shielding afforded was found. This indicates the need for local assessment of cap efficiency according to the practice.
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Exposição Ocupacional , Doses de Radiação , Proteção Radiológica , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controleRESUMO
After WWII, global concerns about the uses of nuclear energy and radiation sources in agriculture, medicine, and industry brought about calls for radiation protection. At the beginning of the 1960s radiation protection involved the identification and measurement of all sources of radiation to which a population was exposed, and the evaluation and assessment of populations in terms of the biological hazard their exposure posed. Mexico was not an exception to this international trend. This paper goes back to the origins of the first studies on the effects of radiation and on radioprotective compounds in the Genetics and Radiobiology Program of the National Commission of Nuclear Energy founded in 1960, at a time when the effects of radiation on living beings and radiation protection demanded the attention of highly localized groups of scientists and the creation of international as well as national institutions, and its connection to dosimetry and radiation protection until the 1990s. This historical reconstruction examines the circulation of knowledge, scientists, and their material and cognitive resources, to show that radiobiology, with dosimetry and radiation protection as cases in point, not only were carried out with high international standards in parallel with international agencies, but also reflected local material needs, including the standardization of new experimental techniques.
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Energia Nuclear , Proteção Radiológica , História do Século XX , Agências Internacionais , México , RadiobiologiaRESUMO
RESUMEN Introducción: La Radiobiología es la ciencia perteneciente a la biología que estudia los efectos de los distintos tipos de radiación sobre la materia viva. Objetivo: Identificar la evidencia científica respecto a la radioterapia del paciente con cáncer en la región maxilofacial. Métodos : Se realizó una revisión de la de literatura acerca del tema en motores de búsqueda como: las bases de datos electrónicas PubMed, Medline, Cochrane, Hinari y SciELO. Para la búsqueda de la información se utilizaron las palabras clave: cáncer de cabeza y cuello, tratamiento del cáncer de la región maxilofacial, radioterapia, braquiterapia y tipos de radioterapia. Resultados: Para el tratamiento se necesita evaluar las características del tumor y determinar el estadio tumoral, la localización y extensión de la enfermedad, así como los hallazgos patológicos que dictan la conducta adecuada como la cirugía, radioterapia, quimioterapia, terapia hormonal, inmunoterapia y terapia dirigida. La dosis máxima tolerada en relación con los órganos críticos oscila entre 50 y 76 Gy. Con la braquiterapia se puede colocar la fuente radiactiva dentro del paciente en cavidades anatómicas cerca del tumor o en el lecho tumoral. Esto permite administrar dosis elevadas de irradiación muy eficaces, al tumor o zona de riesgo. Los efectos adversos de las radiaciones ionizantes según la célula afectada pueden ser daño genético y somático. Conclusiones: En el tratamiento del cáncer la radioterapia es una opción primordial, siempre con el precepto que ofrezca buenos resultados en cuanto a eficacia, tolerabilidad y calidad de vida, al causar el menor daño posible a los enfermos y con las nuevas tecnologías puede incrementar el éxito y garantizar que el procedimiento continúe con calidad.
Introduction: Radiobiology is the science belonging to the biology that studies the effects of the different types of radiation on the lively matter. Objective: Identifying the scientific evidence in relation to radiation therapy of the patient with cancer of the maxillofacial region. Methods: A literature revision was carried out in search engines as: The electronic data bases PubMed, Medline, Cochrane, Hinari, and SciELO. For the search for information the key words used were head and neck cancer, treatment of the cancer of the maxillofacial region, radiation therapy, brachytherapy and types of radiation therapy. Results: For the treatment it is needed to evaluate the characteristics of the tumor and to determine the tumor stage, the location and extension of disease, as well as the pathological findings that dictate the conduct made suitable like the surgery, radiation therapy, chemotherapy, hormonal therapy, immunotherapy and directive therapy. The maximum dose tolerated relating to the critical organs oscillates between 50 and 76 Gy. With the brachytherapy the radioactive source inside the patient can place itself in reservoirs, close to the tumor or in the tumor area. This allows managing dose lifted of irradiation very effective, to the tumor or zone of risk. The adverse effects of the ionizing radiations according to the impaired cell can be genetic and somatic damage. Conclusions: In the treatment of cancer, radiation therapy is a primary option, always with the precept that offers good results as to efficacy, tolerance and quality of life, causing the smaller possible damage to the sick and with the new technologies it can increase success and guarantee that a procedure keeps on being high-quality.
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Resumen El uso de rayos X juega un papel esencial en el diagnóstico y planificación de tratamientos dentales. Los avances tecnológicos de los equipos de rayos X han contribuido al mayor uso de este tipo de radiación en la práctica odontológica. Aunque la exposición a la radiación es baja en estos procedimientos, todavía existe un riesgo que debe reducirse al mínimo necesario a fin de obtener una imagen adecuada para el diagnóstico y a la vez evitar efectos nocivos para el paciente y el personal involucrado. Debido al alto y creciente número de radiografías dentales, el hecho de que niños y adolescentes sean el foco de la mayoría de estas, la subestimación de la cantidad de exámenes radiológicos reportados y la supuesta baja conciencia de estudiantes y profesionales de la odontología sobre los peligros del uso indiscriminado de los rayos X, es necesario adoptar medidas de protección radiológica para mitigar los efectos biológicos radioinducidos. Este artículo tiene como objetivo revisar los principios básicos de la radioprotección que deben considerarse en la práctica dental, con el fin de garantizar el menor daño posible a trabajadores ocupacionalmente expuestos, pacientes y miembros del público.
Resumo O uso dos raios X desempenha um papel essencial no diagnóstico e planejamento de tratamentos dentários. O avanço tecnológico nos equipamentos de raios-X tem contribuído para o aumento do uso deste tipo de radiação na prática odontológica. Embora a exposição à radiação seja baixa nestes procedimentos, ela representa um risco e deve ser reduzida ao mínimo valor necessário para se obter a imagem adequada para o diagnóstico, evitando efeitos nocivos ao paciente e ao pessoal envolvido. Devido ao elevado e crescente número de radiografias odontológicas, ao fato de crianças e adolescentes serem o foco de grande parte delas, a subestimação do número de exames radiológicos notificados e a suposta baixa conscientização de estudantes e profissionais da odontologia sobre os perigos dos uso indiscriminado de raios-x, é precisa a adoção de medidas de radioproteção para mitigar o risco de efeitos nocivos radioinduzidos. Este artigo tem como objetivo revisar os princípios básicos da radioproteção a serem considerados na prática odontológica, a fim de garantir o menor prejuízo possível para trabalhadores ocupacionalmente expostos, pacientes e membros do público.
Abstract The use of X-rays plays an essential role in the diagnosis and planning of dental treatments. Technological advances in X-ray equipment have contributed to the increased use of this type of radiation in dental practice. Although radiation exposure is low in these procedures, there is still a risk. The reduction of the risk to the minimum value possible is necessary to obtain an adequate image for the diagnosis and avoiding harmful effects on the patient and the personnel involved. Due to the high and growing number of dental X-rays, the fact that children and adolescents are the focus of most of them, the underestimation of the number of radiological examinations reported and the supposed low awareness of dental students and professionals about the dangers the indiscriminate use of X-rays, it is necessary to adopt radioprotection measures to mitigate the risk of harmful radioinduced effects. This article aims to review the basic principles of radioprotection to be considered in dental radiology, in order to ensure the least possible damage to occupationally exposed workers, patients and public members.
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Five decades ago, Franz Halberg conceived the idea of ââa circadian-based therapy for cancer, given the differential tolerance to treatment derived from the intrinsic host rhythms. Nowadays, different experimental models have demonstrated that both the toxicity and efficacy of several anticancer drugs vary by more than 50% as a function of dosing time. Accordingly, it has been shown that chemotherapeutic regimens optimally timed with the circadian cycle have jointly improved patient outcomes both at the preclinical and clinical levels. Along with chemotherapy, radiation therapy is widely used for cancer treatment, but its effectiveness relies mainly on its ability to damage DNA. Notably, the DNA damage response including DNA repair, DNA damage checkpoints, and apoptosis is gated by the circadian clock. Thus, the therapeutic potential of circadian-based radiotherapy against cancer is mainly dependent upon the control that the molecular clock exerts on DNA repair enzymes across the cell cycle. Unfortunately, the time of treatment administration is not usually considered in clinical practice as it varies along the daytime working hours. Currently, only a few studies have evaluated whether the timing of radiotherapy affects the treatment outcome. Several of these studies show that it is possible to reduce the toxicity of the treatment if it is applied at a specific time range, although with some inconsistencies. In this Perspective, we review the main advances in the field of chronoradiotherapy, the possible causes of the inconsistencies observed in the studies so far and provide some recommendations for future trials.
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The Granada group in BNCT research is currently performing studies on: nuclear and radiobiological data for BNCT, new boron compounds and a new design for a neutron source for BNCT and other applications, including the production of medical radioisotopes. All these activities are described in this report.
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Terapia por Captura de Nêutron de Boro/métodos , Aceleradores de Partículas , Humanos , Método de Monte Carlo , NêutronsRESUMO
BACKGROUND: Calvaria skin has a reduced thickness, and its initial damage produced by irradiation was scarcely reported. We aimed to identify the initial effects of x-ray irradiation in the rat calvaria skin. METHODS: After approval by the Animal Ethical Committee, calvaria skin sections of five Wistar rats per time point were evaluated on days 4, 9, 14, and 25 following a single 15-Gy x-ray irradiation of the head. The control group was composed of five rats and evaluated on day 4. Sections were assessed using hematoxylin-eosin and Masson's trichrome staining for morphology, inflammation, and fibrosis. Fibrosis was also evaluated by the collagen maturation index from Picrosirius red staining and by cell proliferation using the immunohistochemistry, after 5-bromo-2-deoxyuridine intraperitoneal injection. RESULTS: In irradiated rats, we observed a reduction in epithelial cell proliferation (p = 0.004) and in matrix metalloproteinase-9 expression (p < 0.001), an increase in the maturation index, and with a predominance in the type I collagen fibers, on days 9 and 14 (1.19 and 1.17, respectively). A progressive disorganization in the morphology of the collagen fibers at all time points and changes in morphology of the sebaceous gland cells and hair follicle were present until day 14. CONCLUSIONS: The initial damage produced by a single 15-Gy x-ray irradiation to the rat calvaria skin was a change in the normal morphology of collagen fibers to an amorphous aspect, a temporary absence of the sebaceous gland and hair follicles, and without a visible inflammatory process, cell proliferation, or fibrosis process in the dermis.
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Lesões por Radiação/patologia , Pele/efeitos da radiação , Animais , Proliferação de Células , Masculino , Ratos , Ratos Wistar , Crânio/efeitos da radiação , Coloração e Rotulagem , Raios XRESUMO
PURPOSE: To investigate the effects of high dose rate (HDR) brachytherapy on cellular progression of a radioresistant human squamous cell carcinoma in vitro, based on clinical parameters. MATERIALS AND METHODS: An acrylic platform was designed to attach tissue culture flasks and assure source positioning during irradiation. At exponential phase, A431cells, a human squamous cell carcinoma, were irradiated twice up to 1100 cGy. Cellular proliferation was assessed by Trypan blue exclusion assay and survival fraction was calculated by clonogenic assay. DNA content analysis and cell cycle phases were assessed by flow cytometry and gel electrophoresis, respectively. Cellular death patterns were measured by HOPI double-staining method. RESULTS: Significant decreasing cellular proliferation rate (p < 0.05) as well as reduced survival fraction (p < 0.001) in irradiated cells were observed. Moreover, increased percentage of cells arrested in the G2/M phase (32.3 ± 1.5%) in the irradiated group as compared with untreated cells (8.22 ± 1.2%) was detected. Also, a significant (p < 0.0001) nuclei shrinking in irradiated cells without evidence of necrosis or apoptosis was found. CONCLUSION: HDR brachytherapy led to a decreased proliferation rate and cell survival and also hampered cellular progression to mitosis suggesting that tumor cell death mainly occurred due to mitotic death and G2/M cell cycle arrest.
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Apoptose/efeitos da radiação , Braquiterapia/métodos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Ciclo Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Humanos , Hipofracionamento da Dose de Radiação , Resultado do TratamentoRESUMO
Objetivo: Avaliar o conhecimento de cirurgiões-dentistas da cidade de Patos-PB acerca da biossegurança em radiologia odontológica e métodos de proteção utilizados. Métodos: Foi utilizada uma abordagem indutiva com procedimento estatístico descritivo e técnica de documentação direta através da pesquisa de campo, utilizando o formulário como instrumento. Participaram do estudo 50 cirurgiões-dentistas que trabalhavam em consultórios particulares com aparelho de raios X intraoral na cidade de Patos-PB. Após a assinatura do Termo de Consentimento Livre e Esclarecido pelos profissionais, foram aplicados questionários para avaliação do conhecimento dos mesmos sobre biossegurança em radiologia e práticas de proteção utilizadas. Os dados foram tabulados e foi feita análise descritiva das variáveis qualitativas pelas medidas de proporção, frequências e porcentagens. Resultados: Observou-se que todos os profissionais mostraram preocupação em relação à radioproteção e que buscavam realizar os exames radiográficos seguindo os princípios de cada técnica radiográfica a fim de se evitar a repetição das mesmas. Para proteção do paciente, a maioria relatou utilizar avental de chumbo, incluindo protetor de tireóide, além de reduzir o tempo de exposição. Acerca da proteção própria, a maior parte afirmou possuir paredes com revestimento de chumbo. Conclusão: Observouse que a maioria dos profissionais tem conscientização acerca dos aspectos de radioproteção, contudo, alguns cirurgiões-dentistas ainda desconhecem os mesmos e não praticam a biossegurança em radiologia, colocando em risco sua própria saúde e a dos pacientes.(AU)
Aim: To assess the knowledge of dentists in the city of Patos, PB, Brazil, about biosafety in radiology and applied protection methods. Methods: This study involved an inductive approach with a descriptivestatistical procedure and a research technique for direct documentation in the field, using a questionnaire as the main instrument. This study included 50 dentists who work in private practices with intraoral X-ray units in Patos, PB. After the professionals had signed the Free and Informed Consent Form, questionnaires were applied to evaluate the dentists' knowledge about biosafety in radiology and their protection practices. The data were tabulated, and a descriptive analysis was performed regarding the qualitative variables measured by proportion, frequencies, and percentages. Results: It was observed that all of the staff were concerned about their own radioprotection and that they sought to comply with the principles of each radiographic technique in order to avoid repeating radiographs. For patient protection, the majority reported using lead aprons, including a thyroid shield, in addition to reducing exposure time. Regarding their own protection, most facilities have walls with lead casing. Conclusion: It was observed that most professionals are aware of the aspects of radiological protection; however, some are still unfamiliar with these procedures and do not practice biosafety in radiology, putting their own health and that of their patients at risk.(AU)
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Odontólogos , Proteção Radiológica , Radiologia , Conhecimentos, Atitudes e Prática em Saúde , RadiobiologiaRESUMO
Understanding the fundamental mechanisms involved in the induction of biological damage by ionizing radiation remains a major challenge of today's radiobiology research. The Monte Carlo simulation of physical, physicochemical and chemical processes involved may provide a powerful tool for the simulation of early damage induction. The Geant4-DNA extension of the general purpose Monte Carlo Geant4 simulation toolkit aims to provide the scientific community with an open source access platform for the mechanistic simulation of such early damage. This paper presents the most recent review of the Geant4-DNA extension, as available to Geant4 users since June 2015 (release 10.2 Beta). In particular, the review includes the description of new physical models for the description of electron elastic and inelastic interactions in liquid water, as well as new examples dedicated to the simulation of physicochemical and chemical stages of water radiolysis. Several implementations of geometrical models of biological targets are presented as well, and the list of Geant4-DNA examples is described.
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DNA/química , Modelos Moleculares , Método de Monte Carlo , Água/química , Fenômenos Químicos , HumanosRESUMO
The advance of medical imaging technology has led to an increase in the medical radiation exposure, especially derived from computed tomography (CT). Recent studies confirm a small but significant increase of cancer cases induced by CT radiation. Children are markedly more sensitive to radiation than adults and in addition, their life expectancy is longer, so we must use all resources to optimize and reduce the exposure dose using the ALARA concept. CT is an important diagnostic tool in medical practice and its benefits far outweigh the costs of radiation if the indication is properly justified.
El avance tecnológico de las imágenes para evaluación de enfermedades ha llevado a un aumento considerable de la radiación de origen médica, principalmente la proveniente de la tomografía computada (TC). Estudios recientes confirman un pequeño pero significativo incremento de casos de cáncer inducidos por radiación generada por la TC. Siendo los niños reconocidamente más sensibles a la radiación que los adultos y sumado a su mayor expectativa de vida, es que debemos usar todos los recursos para optimizar y reducir la dosis de exposición aplicando el concepto de ALARA. La TC es una herramienta diagnóstica importantísima en la práctica médica, y sus beneficios superan ampliamente los costos de la radiación si su indicación está adecuadamente justificada.
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Humanos , Criança , Neoplasias Induzidas por Radiação/etiologia , Tomografia Computadorizada por Raios X/efeitos adversos , Doses de Radiação , Neoplasias Induzidas por Radiação/prevenção & controle , Medição de Risco , Radiografia/efeitos adversosRESUMO
Stereotactic body radiation therapy (SBRT) evolved from the application of stereotactic radiosurgery, which is focused intracranial radiation. SBRT offers high doses of specific radiation with oligofractions (five or less) to a specified target, providing local control to circumscribed tumors while sparing surrounding normal tissue. Commonly treated cancers include tumors of the lung and liver. The challenge with SBRT is to account for organ motion and the achievement of precise targeting. SBRT uses three-dimensional radiation therapy planning, intensity-modulated radiation therapy, as well as image-guided organ motion and gating. SBRT is based on the premise of geometric avoidance, targeting the tumor with the goal of complete avoidance of the surrounding normal tissues and critical organs. An SBRT course of treatment ranges from one to five treatments (hypofractionated) and, therefore, differs from conventional radiation, which is usually a prolonged course ranging from two to six weeks of daily treatment.
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Neoplasias/cirurgia , Radiocirurgia , HumanosRESUMO
Desde hace aproximadamente una década, la oncología ha entrado en una etapa de revolución de la medicina de precisión, donde las características genéticas del tumor son evaluadas para la selección individual de los mejores tratamientos en beneficio del paciente y de los sistemas de salud. La radioterapia es una modalidad terapéutica que es empleada en alrededor del 80% de los pacientes con cáncer. La personalización de la radioterapia se ha basado en las últimas décadas en la búsqueda de mejores formas de entregar dosis de radiación al tumor, mientras se evita exposición de los tejidos sanos mediante sorprendentes y novedosas plataformas tecnológicas, como el desarrollo de intensidad modulada o la radiocirugía, radioterapia intraoperatoria, entre otras. Un área que se ha iniciado, pero que no ha tenido una aplicación inmediata o masiva en la práctica diaria, es la incorporación de la radiogenómica, condiciones radiobiológicas o del micro ambiente tumoral, en la toma de decisiones en la radioterapia. En este art¡culo de revisión exploramos el potencial empleo de bio-marcadores que podrían incorporarse a las nuevas tecnolog¡as en el futuro inmediato con la finalidad de optimizar el tratamiento con radioterapia en procura del mejor control loca.
Since approximately one decade ago, oncology has entered in a period of revolution of precision medicine where genetic characteristics of tumor are evaluated for individual selection of best treatments for the benefit of patients and health systems. Radiation therapy is a therapeutic method which is employed in about 80% of cancer patients. On the last decades, personalization of radiotherapy has been based in the search for better ways to deliver radiation doses to the tumor, while exposing healthy tissue is prevented by surprising and novel technology platforms, such as development or intensity-modulated radiation, radiosurgery, intraoperative radiation therapy, among others. One area that has been initiated but has not had an immediate and massive application in daily practice is the incorporation of radiogenomics, radiobiology conditions or tumor micro environment status in decision-making in radiotherapy. In this review article we explore the potential use of biomarkers that could be incorporated into the new technologies in the near future in order to optimize radiotherapy treatment in pursuit of better local control of disease and lower occurrence of complications.
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Radiobiologia , RadioterapiaRESUMO
La biodosimetría citogenética se aplica en la evaluación médica de las personas involucradas en situaciones radiológicas anormales, con el fin de evaluar las dosis recibidas, el peligro inminente para la salud y aplicar los tratamientos médicos más adecuados. Además, contribuye al esclarecimiento de sucesos cuando existen dudas respecto a los resultados de la dosimetría física por dosímetros defectuosos, no calibrados o ausentes. Es el método más preciso de dosimetría biológica, ya que existe una relación matemática que permite calcular la dosis, establecer el grado de homogenidad de la exposición y, en caso de exposiciones no homogéneas, establecer la fracción del cuerpo irradiada y la dosis que recibió esa fracción mediante la cuantificación del número y tipos de aberraciones cromos¢micas y de micronúcleos y su distribución en los linfocitos de la sangre periférica. Para este análisis se establecen las relaciones dosis-efecto y un sistema automatizado para el cálculo de las dosis de radiación recibidas. Actualmente se está desarrollando un proyecto conjunto Universidad de Costa Rica-Hospital San Juan de Dios, con el objetivo de explorar los efectos cromosómicos de la radiación, en pacientes expuestos por razones el objetivo de explorar los efectos cromosómicos de la radiación, en pacientes expuestos por razones terapéuticas y atendidos en este hospital. De igual modo, se hará la curva de calibración dosis-respuesta in vitro para rayos gama y se validar mediante la intercomparación con el Laboratorio de Dosimetría Citogenética de Centro para la Protección e Higiene de las Radiaciones de Cuba...
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Humanos , Citogenética , Liberação Nociva de Radioativos/classificação , Exposição à Radiação , Radiação Ionizante , Radiobiologia , RadiometriaRESUMO
Objetivo: Presentar los principales conceptos de radiobiología, radioterapia en cavidadoral y complicaciones asociadas, para llevar a cabo acciones seguras de tipo preventivo yterapéutico por parte del profesional o del equipo tratante. Método: La revisión se llevó acabo en diferentes bases de datos y revistas acerca del manejo odontológico de pacientessometidos a radioterapia. Resultados: Actualmente, el tratamiento para el cáncer tiene unenfoque multidisciplinario, en el cual participan distintos profesionales de la salud (incluidoel odontólogo) en las fases de diagnóstico, tratamiento específico mediante extirpaciónquirúrgica, tratamiento citotóxico con quimioterapia y radiaciones ionizantes, y rehabilitación.La radioterapia trae consigo complicaciones producto de la interacción de las radiacionesionizantes con el organismo: efectos de tipo físico, químico y biológico, debido a lainteracción entre las partículas cargadas y los átomos del tejido irradiado. Adicionalmente,se llevan a cabo reacciones enzimáticas que reparan la mayoría de las lesiones radioinducidas,como daños en el ADN, y los principales efectos radiobiológicos negativos o adversos.En la cavidad oral se presentan complicaciones de tipo agudo como mucositis, xerostomíay riesgo de infección; al igual que reacciones tardías como alteración en la vascularizaciónde hueso y mucosa, daño en glándulas salivares, reducción celular en el tejido conectivo yriesgo de incremento en la síntesis de colágeno, lo que resulta en fibrosis y produce tejidoshipovasculares, hipocelulares e hipóxicos, que afectan al hueso, pues reduce su capacidadde remodelación e incrementa su riesgo de infección y osteorradionecrosis...
Objective: To introduces the main concepts in radiobiology, radiotherapy in the oral cavity,and complications associated with them, in order to carry out preventive and curativeactions safely by the health professional and team. Method: The review was performed inseveral databases and journals on the dental care of patients undergoing radiotherapy. Results:Currently, treatment for cancer is carried out through a multidisciplinary approach withdifferent health professionals (including dentists) participating to determine its diagnosis,specific treatment through surgical removal, cytotoxic treatment with chemotherapy and/or ionizing radiation, and rehabilitation. Radiotherapy produces complications as a reactionbetween the ionizing radiation and the body: Physical, chemical and biological effects due tointeractions between the charged particles and the atoms of the irradiated tissue; in addition,enzymatic reactions take place to repair most of the radioinduced lesions, like damagein the DNA, the main negative or adverse radiobiological effects. In the oral cavity, there areacute reactions such as mucositis, xerostomia and risk of infection, as well as late reactionssuch as alterations of bone and mucose vascularization, saliva gland damage, cell reductionin connective tissue, and risk of collagen synthesis increase, which results in fibrosis andhypovascular, hypocellular and hypoxic tissues that affect bones because its remodelingcapacity is diminished and the risk of infection and osteor adionecrosis is incr eased...
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Braquiterapia/métodos , Mucosite , Neoplasias Bucais , Neoplasias Bucais/tratamento farmacológico , Osteonecrose , Radioterapia de Intensidade Modulada , XerostomiaRESUMO
OBJETIVO: Avaliar os efeitos da radiação ionizante sobre o paladar, em pacientes que foram submetidos a radioterapia na região de cabeça e pescoço. MATERIAIS E MÉTODOS: Foram selecionados 20 pacientes que possuíam diagnóstico de tumor na região de cabeça e pescoço, que iniciaram tratamento no Setor de Radioterapia da Santa Casa de Misericórdia de Belo Horizonte, MG, Brasil. Para testes do paladar, foram manipuladas quatro soluções (salgada - NaCl; doce - sacarose; azeda - ácido cítrico; amarga - ureia) em três concentrações diferentes (fraca, média e forte), administradas por meio de conta-gotas, três gotas de cada solução de maneira aleatória, respeitando a ordem das concentrações fracas, médias e fortes. Após a aplicação de cada solução, o paciente relatava o sabor que sentia. O procedimento foi realizado semanalmente durante as três primeiras semanas de radioterapia. RESULTADOS: Foi observada diferença estatisticamente significante na perda do paladar dos pacientes em tratamento radioterápico, quando se compararam a 1ª e 4ª semanas de tratamento na solução salgada, nas três concentrações, na solução doce nas concentrações fracas e médias e nas soluções azedas e amargas, apenas quando se testaram as concentrações fracas. CONCLUSÃO: A radiação ionizante altera o paladar de pacientes submetidos a radioterapia de cabeça e pescoço.
OBJECTIVE: To evaluate the effects of ionizing radiation on the taste function in patients submitted to radiotherapy in the head and neck region. MATERIALS AND METHODS: Twenty patients diagnosed with head and neck tumors and undergoing treatment in the Division of Radiotherapy at Santa Casa de Misericórdia de Belo Horizonte, MG, Brazil, were selected. For their taste function testing, four solutions were manipulated with salt (NaCl), sugar (sucrose), citric acid (for acidity), and urea (for bitterness), at three different (low, medium and high) concentrations. Weekly tests were performed during the first three weeks of radiotherapy, with random administration of the solutions (three drops each) respecting the order of their concentration levels (low, medium and high). After the application of each solution, the patient reported which flavor he/she tasted. RESULTS: A statistically significant difference was observed in the loss of taste function as the results in the 1st and 4th weeks of treatment were compared, with salty solution at the three concentration levels, with the sweet solution at low and medium concentrations, and with the sour and bitter solutions, only at low concentration. CONCLUSION: Ionizing radiation alters the taste function of patients submitted to head and neck radiotherapy.
Assuntos
Humanos , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Ageusia , Ageusia/complicações , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço , Anamnese , Radiação Ionizante , Radiobiologia , Radioterapia/efeitos adversos , PaladarRESUMO
Objetivo: Realizar uma pesquisa em consultórios odontológicos na cidade de São José do Rio Preto - SP sobre conhecimento e atitudes dos profissionais sobre proteção radiológica e comparar os dados com as recomendações da Portaria 453 do Ministério da Saúde. Material e Método: Cento e cinqüenta consultórios odontológicos foram visitados e foi aplicado um questionário. Resultados: Observou-se que 26% dos entrevistados não conheciam a lei, 23% não avaliavam radiografias existentes do paciente, 21% não usavam vestimenta plumbífera nos pacientes, 49% não usavam posicionadores de filmes, 58% ainda utilizavam processamento visual; 93% utilizavam filme E ou F, entretanto a média de tempo de exposição foi 0.5 segundo, 14% dos equipamentos possuíam cone localizador e 83% seletor de tempo manual, 17% dos dentistas não se protegiam durante a exposição do paciente e 64% ainda utilizavam disparador com retardo. Conclusão: Há falta de conhecimento sobre proteção radiológica; um programa educacional em Radiologia pode produzir mudanças nas atitudes dos profissionais em relação ao uso da radiação ionizante.
Objective: To perform a research in dental offices in the city of São José do Rio Preto-SP about the practitioners' knowledge and attitudes related to radiological protection and compare the data with the recommendations of Ordinance 453 of the Health Ministry. Material and Methods: One hundred and fifty dental offices were visited and a questionnaire was applied. Results: Was observed that 26% of the interviewed did not know the law, 23% did not evaluate the patient's existing radiographs, 21% did not wear lead clothing in patients, 49% did not use film positioners, 58% still used visual processing, 93% used film E or F, however the average exposure time was 0.5 second, 14% of the equipment had locator cone and 83% had manual time selector, 17% of dentists do not protect themselves during the patient's exposure and 64% still used delayed trigger. Conclusion: There Atitudes dos Cirurgiões-Dentistas em Relação à Proteção Radiológica, de Acordo com a Lei Brasileira Pesquisa Rev Odontol Bras Central 2010;19(51) 305 is a lack of knowledge about radiological protection. An educational program in Radiology can produce changes in attitudes of professionals regarding the use of ionizing radiation.