This document discusses radiation and its uses in dentistry. It begins with an overview of the electromagnetic spectrum and different types of radiation. Radiation has benefits in medical diagnosis and treatment through uses like x-rays, gamma rays for sterilization, and nuclear medicine. In dentistry, x-rays are commonly used for diagnostic purposes to detect issues like dental caries, periodontal disease, cysts and tumors. Radiation also has therapeutic uses in dentistry through procedures like radiotherapy for malignant diseases. The document outlines several specific diagnostic imaging techniques used in dentistry like bitewings, periapicals and panoramic x-rays.
This document summarizes the biological effects of radiation at various levels of organization. It discusses:
1. The interaction of radiation with DNA and cells, including direct and indirect effects on DNA.
2. The cellular response to radiation damage, including stochastic and deterministic effects, DNA repair mechanisms, and factors influencing radiosensitivity.
3. Tissue and organ responses like acute radiation syndrome and late effects like fibrosis and osteoradionecrosis.
4. Genetic and carcinogenic risks of radiation exposure, especially for children and developing embryos.
The term LASER is an acronym for ‘Light Amplification by the Stimulated Emission of Radiation’. As its first application in dentistry by Miaman, in 1960, the laser has seen various hard and soft tissue applications. In the last two decades, there has been an explosion of research studies in laser application. In hard tissue application, the laser is used for caries prevention, bleaching, restorative removal and curing, cavity preparation, dentinal hypersensitivity, growth modulation and for diagnostic purposes, whereas soft tissue application includes wound healing, removal of hyperplastic tissue to uncovering of impacted or partially erupted tooth, photodynamic therapy for malignancies, photostimulation of herpetic lesion. Use of the laser proved to be an effective tool to increase efficiency, specificity, ease, and cost and comfort of the dental treatment.
Role of oral radiology in forensic dentistry [autosaved]/ oral surgery courses Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
Digital imaging has advantages over conventional radiography. Digital images can be enhanced by adjusting contrast and brightness or applying filters. Measurements can also be performed directly on digital images. This allows for image analysis functions like linear measurements. Digital imaging also decreases radiographic working time as images are available immediately and there is no film processing. However, digital images have less contrast compared to conventional films.
explained with Limited matter moreover I have included all the images. if you go through a standard textbook and referred to this PPT it will help you so much I hope It helps you
Theranostics involves using radiolabeled agents for both diagnosing and treating diseases. Iodine-131 was one of the first theranostic agents used for both imaging and treating thyroid conditions. Other promising theranostic nuclides discussed include iodine-123, iodine-124, gallium-68, lutetium-177, copper-64, copper-67, tin-117m, and fluorine-18 FDG which shows potential for imaging and cytotoxic effects against cancer cells. Effective theranostic agents require properties like appropriate half-lives and radiation types to enable both diagnostic imaging and therapeutic doses to diseased sites.
This document provides an overview of lasers used in dentistry, including their history, mechanisms of action, applications, and safety measures. It discusses how lasers were first developed in the 1960s and introduced to dentistry in the 1990s. The main types of lasers used include CO2, Nd:YAG, Er:YAG, and KTP lasers. Lasers can be used for both hard and soft tissue procedures, such as caries removal, gingivectomies, and lesion removal, with advantages like reduced pain, bleeding, and recovery time compared to traditional techniques. Safety precautions must be followed when using lasers to protect patients and operators.
This document summarizes the biological effects of radiation at various levels of organization. It discusses:
1. The interaction of radiation with DNA and cells, including direct and indirect effects on DNA.
2. The cellular response to radiation damage, including stochastic and deterministic effects, DNA repair mechanisms, and factors influencing radiosensitivity.
3. Tissue and organ responses like acute radiation syndrome and late effects like fibrosis and osteoradionecrosis.
4. Genetic and carcinogenic risks of radiation exposure, especially for children and developing embryos.
The term LASER is an acronym for ‘Light Amplification by the Stimulated Emission of Radiation’. As its first application in dentistry by Miaman, in 1960, the laser has seen various hard and soft tissue applications. In the last two decades, there has been an explosion of research studies in laser application. In hard tissue application, the laser is used for caries prevention, bleaching, restorative removal and curing, cavity preparation, dentinal hypersensitivity, growth modulation and for diagnostic purposes, whereas soft tissue application includes wound healing, removal of hyperplastic tissue to uncovering of impacted or partially erupted tooth, photodynamic therapy for malignancies, photostimulation of herpetic lesion. Use of the laser proved to be an effective tool to increase efficiency, specificity, ease, and cost and comfort of the dental treatment.
Role of oral radiology in forensic dentistry [autosaved]/ oral surgery courses Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com
Digital imaging has advantages over conventional radiography. Digital images can be enhanced by adjusting contrast and brightness or applying filters. Measurements can also be performed directly on digital images. This allows for image analysis functions like linear measurements. Digital imaging also decreases radiographic working time as images are available immediately and there is no film processing. However, digital images have less contrast compared to conventional films.
explained with Limited matter moreover I have included all the images. if you go through a standard textbook and referred to this PPT it will help you so much I hope It helps you
Theranostics involves using radiolabeled agents for both diagnosing and treating diseases. Iodine-131 was one of the first theranostic agents used for both imaging and treating thyroid conditions. Other promising theranostic nuclides discussed include iodine-123, iodine-124, gallium-68, lutetium-177, copper-64, copper-67, tin-117m, and fluorine-18 FDG which shows potential for imaging and cytotoxic effects against cancer cells. Effective theranostic agents require properties like appropriate half-lives and radiation types to enable both diagnostic imaging and therapeutic doses to diseased sites.
This document provides an overview of lasers used in dentistry, including their history, mechanisms of action, applications, and safety measures. It discusses how lasers were first developed in the 1960s and introduced to dentistry in the 1990s. The main types of lasers used include CO2, Nd:YAG, Er:YAG, and KTP lasers. Lasers can be used for both hard and soft tissue procedures, such as caries removal, gingivectomies, and lesion removal, with advantages like reduced pain, bleeding, and recovery time compared to traditional techniques. Safety precautions must be followed when using lasers to protect patients and operators.
Early detection of oral cancer can save lives. Oral cancer involves regions in the oral cavity and oropharynx, including the lips, tonsils, tongue, cheeks and other areas. Precancerous lesions and conditions can be detected through visual examination techniques like toluidine blue staining, VELscope, chemiluminescence and the Identafi system. Salivary biomarkers like proteins, genes, microbiota, oxidative stress markers and interleukins also show promise for early detection of oral cancer. Genetic changes in oncogenes and tumor suppressor genes influence tumor proliferation, progression, angiogenesis and metastasis.
This document discusses staging and grading systems for oral squamous cell carcinoma. It describes the TNM and STNMP staging systems which classify tumors based on size, nodal involvement, and metastasis. Grading systems discussed include Broder's, WHO, Jakobsson's, Anneroth's, Bryne's, and histologic risk models which classify tumors based on differentiation and other microscopic features. Accurately staging and grading tumors is important for prognostication, treatment planning, and evaluating treatment response.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses digital radiography in dentistry. It provides an introduction to digital radiography, comparing analog and digital images. It describes the various components of a digital system including sensors, imaging systems, and advantages/disadvantages over analog radiography. The document discusses the different types of sensors in detail and their uses in digital imaging techniques. It also addresses legal aspects and concludes that while film-based imaging is still used, digital imaging offers advantages and is becoming more widely accepted.
This document discusses osteoradionecrosis of the jaws, which is bone necrosis caused by radiation therapy for head and neck cancer. It defines osteoradionecrosis and describes its classification, types, risk factors, and theories of pathophysiology. The document outlines protocols for preventing and treating osteoradionecrosis, including conservative management, hyperbaric oxygen therapy, pentoxifyllin and tocopherol supplements, and surgical interventions. Hyperbaric oxygen therapy is described as an adjuvant treatment involving intermittent high-pressure oxygen sessions to promote revascularization and healing.
This document provides an overview of digital radiography. It begins with an introduction to the history and advantages of digital radiography compared to traditional film-based radiography. It then describes different types of digital image receptors including CCD, CMOS, flat panel detectors, and photostimulable phosphor plates. The document explains the process of analog to digital conversion and pixel formation. It provides details on the structure and functioning of different digital receptors. Advantages and disadvantages of each receptor type are also summarized.
transcrestal sinus lift with implant placement-balloon techniquespsangeetaporiya
The document summarizes a study on using a balloon technique for transcrestal sinus lift. The technique involves inserting a latex balloon through the alveolar crest and insufflating it with saline to detach the sinus membrane. The study found the technique was effective for lifting the sinus membrane up to 10 mm in height and had few complications. It performed the technique in 6 patients with 3 mm or less of residual bone, gaining an average of 8.7 mm in height, and found a 100% implant success rate one year after loading. The document concludes the balloon technique is a minimally invasive option that is well-suited for sinus lifting when residual bone is 3 mm or less.
This document provides an overview of cone beam computed tomography (CBCT) including its history, components, principles, and applications in dentistry. Some key points:
- CBCT was first introduced in the 1990s and provides 3D imaging with lower radiation dose than medical CT. It works by generating a cone-shaped X-ray beam and using a detector to record attenuation data, which is then reconstructed into 3D images.
- Components include an X-ray generator, image sensor, and software for image reconstruction. Images are stored in DICOM format.
- Advantages include rapid scan time, interactive display modes, and ability to view structures in multiple planes. Disadvantages include potential artifacts and inability to view
This document discusses the various applications of lasers in endodontics. It outlines 10 main uses of lasers including analgesia, pulp diagnosis, pulpotomy, pulpectomy, root canal treatment, apical surgery, bleaching, dentinal hypersensitivity, sterilization of dental instruments, and treatment of incomplete tooth fractures. For each use, it provides details on the specific lasers used (such as Nd:YAG, Er:YAG), how they work, and their advantages over traditional methods. It also lists some contraindications and references several textbooks and studies on the topic.
1. The document classifies and describes several diseases that can affect the jaw bone, including inflammatory, hereditary, metabolic, and neoplastic diseases.
2. Several primary bone tumors are described in detail, including osteoma, osteoid osteoma, osteoblastoma, osteosarcoma, osteochondroma, chondroma, chondrosarcoma, giant cell tumor, Ewing's sarcoma, and multiple myeloma.
3. For each tumor, the clinical features, radiographic appearance, and histopathology are summarized to aid in diagnosis and classification of jaw bone diseases.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses oral squamous cell carcinoma (OSCC). It begins with an introduction stating OSCC is the 8th most common cancer in males and 15th in females worldwide. Tobacco, alcohol, HPV infection, iron deficiency, and vitamin deficiencies are identified as risk factors. The document then discusses the pathogenesis of OSCC in more detail for different risk factors. Clinical features, histopathological features, variants of OSCC, and staging are also summarized. References are provided at the end.
this contains the occlusal radiography methods for both maxillary and mandibular different occusal radiographic techniques, principles, classification, indications
Review on the applications of ultrasonography in dentistry - Dr Sanjana RavindraDr. Sanjana Ravindra
Ultrasonography has various applications in the dentomaxillofacial region for evaluating soft tissue masses, salivary gland and duct calculi, vascular structures, and assisting with biopsies. It can assess conditions like TMJ disorders, intraosseous lesions, lymph node metastasis, and soft tissue lesions. Ultrasonography is a useful imaging technique as it uses non-ionizing sound waves to generate real-time images without radiation exposure. However, its ability to image deep structures and penetrate bone is limited compared to other modalities.
Advanced radiographic aids in periodonticsSwati Gupta
Digital radiography and imaging techniques like digital subtraction radiography, computer-assisted densitometric image analysis, and computed tomography provide more accurate and quantitative assessments of periodontal bone levels compared to conventional radiography. These advanced techniques allow for early detection of bone loss, longitudinal monitoring of treatment outcomes, and three-dimensional imaging. However, many require specialized equipment and high levels of standardization for calibration.
This presentation gives an outline about all advanced imaging modalities of Head and Neck which includes both hard tissue and soft tissue. Their basic principles, indications, advantages and limitations.
This document outlines various medical imaging techniques and their uses in surgery. It discusses the history of imaging, including the discoveries of x-rays and CT scans. The main imaging modalities covered are x-rays, ultrasound, CT, MRI, and nuclear medicine. The document explores how different specialties like general surgery, urology, and orthopedics use imaging for diagnostic and interventional purposes. It concludes by noting that imaging is a valuable tool but not a substitute for clinical skills, and that communication between surgeons and radiologists is important.
This document provides an introduction to diagnostic radiography. It discusses what diagnostic radiography is, the early history of radiography dating back to Wilhelm Roentgen's discovery of x-rays in 1895. It then describes several common diagnostic imaging modalities used today including conventional x-ray, fluoroscopy, ultrasound, CT scanning, and MRI. Each modality is briefly explained in terms of its benefits, risks, and applications. The document concludes with a short section on the history and current state of diagnostic radiography in Ghana.
Early detection of oral cancer can save lives. Oral cancer involves regions in the oral cavity and oropharynx, including the lips, tonsils, tongue, cheeks and other areas. Precancerous lesions and conditions can be detected through visual examination techniques like toluidine blue staining, VELscope, chemiluminescence and the Identafi system. Salivary biomarkers like proteins, genes, microbiota, oxidative stress markers and interleukins also show promise for early detection of oral cancer. Genetic changes in oncogenes and tumor suppressor genes influence tumor proliferation, progression, angiogenesis and metastasis.
This document discusses staging and grading systems for oral squamous cell carcinoma. It describes the TNM and STNMP staging systems which classify tumors based on size, nodal involvement, and metastasis. Grading systems discussed include Broder's, WHO, Jakobsson's, Anneroth's, Bryne's, and histologic risk models which classify tumors based on differentiation and other microscopic features. Accurately staging and grading tumors is important for prognostication, treatment planning, and evaluating treatment response.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses digital radiography in dentistry. It provides an introduction to digital radiography, comparing analog and digital images. It describes the various components of a digital system including sensors, imaging systems, and advantages/disadvantages over analog radiography. The document discusses the different types of sensors in detail and their uses in digital imaging techniques. It also addresses legal aspects and concludes that while film-based imaging is still used, digital imaging offers advantages and is becoming more widely accepted.
This document discusses osteoradionecrosis of the jaws, which is bone necrosis caused by radiation therapy for head and neck cancer. It defines osteoradionecrosis and describes its classification, types, risk factors, and theories of pathophysiology. The document outlines protocols for preventing and treating osteoradionecrosis, including conservative management, hyperbaric oxygen therapy, pentoxifyllin and tocopherol supplements, and surgical interventions. Hyperbaric oxygen therapy is described as an adjuvant treatment involving intermittent high-pressure oxygen sessions to promote revascularization and healing.
This document provides an overview of digital radiography. It begins with an introduction to the history and advantages of digital radiography compared to traditional film-based radiography. It then describes different types of digital image receptors including CCD, CMOS, flat panel detectors, and photostimulable phosphor plates. The document explains the process of analog to digital conversion and pixel formation. It provides details on the structure and functioning of different digital receptors. Advantages and disadvantages of each receptor type are also summarized.
transcrestal sinus lift with implant placement-balloon techniquespsangeetaporiya
The document summarizes a study on using a balloon technique for transcrestal sinus lift. The technique involves inserting a latex balloon through the alveolar crest and insufflating it with saline to detach the sinus membrane. The study found the technique was effective for lifting the sinus membrane up to 10 mm in height and had few complications. It performed the technique in 6 patients with 3 mm or less of residual bone, gaining an average of 8.7 mm in height, and found a 100% implant success rate one year after loading. The document concludes the balloon technique is a minimally invasive option that is well-suited for sinus lifting when residual bone is 3 mm or less.
This document provides an overview of cone beam computed tomography (CBCT) including its history, components, principles, and applications in dentistry. Some key points:
- CBCT was first introduced in the 1990s and provides 3D imaging with lower radiation dose than medical CT. It works by generating a cone-shaped X-ray beam and using a detector to record attenuation data, which is then reconstructed into 3D images.
- Components include an X-ray generator, image sensor, and software for image reconstruction. Images are stored in DICOM format.
- Advantages include rapid scan time, interactive display modes, and ability to view structures in multiple planes. Disadvantages include potential artifacts and inability to view
This document discusses the various applications of lasers in endodontics. It outlines 10 main uses of lasers including analgesia, pulp diagnosis, pulpotomy, pulpectomy, root canal treatment, apical surgery, bleaching, dentinal hypersensitivity, sterilization of dental instruments, and treatment of incomplete tooth fractures. For each use, it provides details on the specific lasers used (such as Nd:YAG, Er:YAG), how they work, and their advantages over traditional methods. It also lists some contraindications and references several textbooks and studies on the topic.
1. The document classifies and describes several diseases that can affect the jaw bone, including inflammatory, hereditary, metabolic, and neoplastic diseases.
2. Several primary bone tumors are described in detail, including osteoma, osteoid osteoma, osteoblastoma, osteosarcoma, osteochondroma, chondroma, chondrosarcoma, giant cell tumor, Ewing's sarcoma, and multiple myeloma.
3. For each tumor, the clinical features, radiographic appearance, and histopathology are summarized to aid in diagnosis and classification of jaw bone diseases.
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.
This document discusses oral squamous cell carcinoma (OSCC). It begins with an introduction stating OSCC is the 8th most common cancer in males and 15th in females worldwide. Tobacco, alcohol, HPV infection, iron deficiency, and vitamin deficiencies are identified as risk factors. The document then discusses the pathogenesis of OSCC in more detail for different risk factors. Clinical features, histopathological features, variants of OSCC, and staging are also summarized. References are provided at the end.
this contains the occlusal radiography methods for both maxillary and mandibular different occusal radiographic techniques, principles, classification, indications
Review on the applications of ultrasonography in dentistry - Dr Sanjana RavindraDr. Sanjana Ravindra
Ultrasonography has various applications in the dentomaxillofacial region for evaluating soft tissue masses, salivary gland and duct calculi, vascular structures, and assisting with biopsies. It can assess conditions like TMJ disorders, intraosseous lesions, lymph node metastasis, and soft tissue lesions. Ultrasonography is a useful imaging technique as it uses non-ionizing sound waves to generate real-time images without radiation exposure. However, its ability to image deep structures and penetrate bone is limited compared to other modalities.
Advanced radiographic aids in periodonticsSwati Gupta
Digital radiography and imaging techniques like digital subtraction radiography, computer-assisted densitometric image analysis, and computed tomography provide more accurate and quantitative assessments of periodontal bone levels compared to conventional radiography. These advanced techniques allow for early detection of bone loss, longitudinal monitoring of treatment outcomes, and three-dimensional imaging. However, many require specialized equipment and high levels of standardization for calibration.
This presentation gives an outline about all advanced imaging modalities of Head and Neck which includes both hard tissue and soft tissue. Their basic principles, indications, advantages and limitations.
This document outlines various medical imaging techniques and their uses in surgery. It discusses the history of imaging, including the discoveries of x-rays and CT scans. The main imaging modalities covered are x-rays, ultrasound, CT, MRI, and nuclear medicine. The document explores how different specialties like general surgery, urology, and orthopedics use imaging for diagnostic and interventional purposes. It concludes by noting that imaging is a valuable tool but not a substitute for clinical skills, and that communication between surgeons and radiologists is important.
This document provides an introduction to diagnostic radiography. It discusses what diagnostic radiography is, the early history of radiography dating back to Wilhelm Roentgen's discovery of x-rays in 1895. It then describes several common diagnostic imaging modalities used today including conventional x-ray, fluoroscopy, ultrasound, CT scanning, and MRI. Each modality is briefly explained in terms of its benefits, risks, and applications. The document concludes with a short section on the history and current state of diagnostic radiography in Ghana.
Forensic radiography uses medical imaging techniques like x-rays, CT scans, MRI, and fluoroscopy to assist with legal investigations and identification of remains. It has applications in determining cause of death, identifying fractures and foreign objects, and aiding in personal identification through analysis of bones and teeth. Radiographers play an important role in forensic radiology by properly recording diagnostic quality images and following ethical standards and safety protocols when working with human remains. Key techniques described include using dental x-rays and analysis of unique bone structures to assist in personal identification of remains.
Radiation has benefits for medical imaging but can harm healthy cells. Proper protection techniques like time, distance and shielding can avoid overexposure, especially for pregnant technicians. Technicians are at risk of radiation exposure and need protection including lead aprons, gloves, glasses and shields to block scatter radiation and stay under exposure limits. New suspended shielding systems aim to improve radiation protection.
This document discusses advances in diagnostic aids for periodontal diseases. It begins by defining diagnostic aids and explaining their importance. It then discusses various categories of diagnostic aids including clinical aids like probing, radiographic aids like digital radiography and subtraction radiography, and microbial diagnostic aids like bacterial culturing, DNA probes, and immunoassays. Newer diagnostic techniques discussed include the perioscope, optical coherence tomography, near-infrared spectroscopy, ultrasound, and confocal laser scanning microscopy. The document emphasizes that while many new techniques show promise, no single tool currently meets all the ideal criteria of an effective diagnostic aid.
Imaging RADIOKLOGY and US for Protozoal Diseases.pptxIbrahimAboAlasaad
To identify the common imaging findings in protozoal diseases, such as malaria, leishmaniasis, amoebiasis, trypanosomiasis, toxoplasmosis, cryptosporidiosis, giardiasis, pneumocystis pneumonia, and babesiosis.
To discuss the strengths and limitations of each imaging technique in the diagnosis and management of protozoal diseases.
RADIOLOGY and US Imaging for Protozoal Diseases.pptxIbrahimAboAlasaad
To understand the basic principles of imaging techniques used in medical parasitology, including X-ray imaging, CT scanning, MRI, ultrasound, endoscopy, and radionuclide imaging.
To identify the common imaging findings in protozoal diseases, such as malaria, leishmaniasis, amoebiasis, trypanosomiasis, toxoplasmosis, cryptosporidiosis, giardiasis, pneumocystis pneumonia, and babesiosis.
This pilot study evaluated the accuracy and correlation of ultrasound (US) imaging in measuring periodontal structures, compared to direct clinical measurements and cone-beam computed tomography (CBCT). 20 participants scheduled for single implant surgery had their papilla height, crestal bone level, soft tissue height, and mucosal thickness measured using US, direct probing, and CBCT. Strong correlations were found between US and direct measurements. US also showed fair to good agreement with CBCT. The study demonstrates US may be a valuable tool for real-time, cross-sectional evaluation of periodontal tissues without radiation. Further research is needed to evaluate US for differentiating healthy from diseased periodontal status.
Radioisotopes have many important medical uses including medical imaging and therapy. Medical imaging techniques like PET scans, SPECT scans, x-rays, MRI, and CT scans use radioactive tracers to create detailed images of the body. Approximately 10% of medical procedures use radiation therapy to treat diseases like cancer. Common radiation therapy methods include external beam radiation, brachytherapy where radioactive sources are placed inside the body, and boron neutron capture therapy. Radioisotopes are crucial for diagnosing and treating millions of patients worldwide each year.
This document discusses radiotherapy techniques for treating various cancers. It begins with statistics on global cancer incidence and mortality. It then describes different radiotherapy techniques including conventional radiotherapy, 3D conformal radiotherapy, intensity-modulated radiotherapy (IMRT), image-guided radiotherapy (IGRT), volumetric modulated arc therapy (VMAT), and PET-guided radiotherapy. Specific techniques for treating head and neck cancers, orbital cancers, and retinoblastoma are also summarized.
When it comes to choosing X-ray machine manufacturers, hospitals follow a rigorous selection process to ensure they make the best decision for their imaging department. Understanding the factors that hospitals consider can shed light on this complex decision-making process. First and foremost, hospitals prioritize the quality and reliability of X-ray machines
Bikrant Roy's physics investigatory project discusses several medical imaging techniques and how physics principles are applied. The document includes sections on X-rays, MRI, CT scans, and some other related areas. It provides details on how each technique works, including diagrams of the machines. Applications and advantages/disadvantages of each method are described. The project was completed under a teacher's guidance and aims to fulfill curriculum requirements for the Central Board of Secondary Education.
This document provides information from a radiation oncologist about cancer treatment. It discusses various types of cancers like lung cancer, breast cancer, colon cancer and their global incidence and mortality rates. It then discusses the role of different specialists in cancer treatment and the role of radiotherapy in head and neck cancers. It provides details about different radiotherapy techniques like 3D conformal radiotherapy, IMRT, IGRT and their advantages. It also discusses radiotherapy procedures for various other cancers like orbital lymphoma, uveal melanoma, retinoblastoma and techniques like plaque brachytherapy.
Dose radiation concern in dental applications from new imaging technologies Osama Albedaiwi
Dental radiology plays an important role in diagnosis but also exposes patients and staff to radiation risks. New dental imaging technologies like CBCT provide more effective 3D imaging but also increase radiation exposure levels. It is important to use the minimum radiation dose needed for quality images and to follow standard protocols to minimize risks from dental radiography.
This document discusses the history and techniques of radiotherapy in ENT. It begins with the discovery of x-rays in 1895 and progresses to modern technologies like IMRT, IGRT, proton beam therapy and SBRT. It covers the physics, biology and mechanisms of radiation therapy. Key aspects of radiotherapy for head and neck cancers like dosimetry, fractionation schedules, acute and chronic toxicities are summarized. Newer conformal techniques aim to reduce normal tissue damage while adequately treating tumors.
Radiation Protection by Irum Khan (Medical Imaging Technologist)irumk746
Radiation Protection
Introduction:Since the announcement of the discovery of X Rays by Röntgen in December 1895, X-rays and the radiological techniques associated with their use have become increasingly central tools in medical diagnosis and management.
As a result of the growth in the usefulness of imaging, other, non-radiation-based, imaging techniques have been developed (e.g. ultrasound and magnetic resonance imaging), and image-guided interventional means of treating patients have become common place. The benefits to patients from these methods of investigation and treatment have been immeasurable.
However, it would be unwise to imagine that no harm can come to patients from the use of radiation-based and other imaging techniques, or from interventional radiology procedures.
Radiation protection is a key aspect of maintaining the safety of patients and Radiation worker in diagnostic and interventional radiology.
Human Responses to Ionizing Radiation DETERMINISTIC EFFECTS OF RADIATION ON HUMANS
1. Acute radiation syndrome
a. Hematologic syndrome
b. Gastrointestinal syndrome
c. Central nervous system syndrome
2. Local tissue damage
a. Skin
b. Gonads
c. Extremities
3. Hematologic depression
4. Cytogenetic damage
STOCHASTIC EFFECTS OF RADIATION ON HUMANS
. Leukemia
2. Other malignant disease
a. Bone cancer
b. Lung cancer
c. Thyroid cancer
d. Breast cancer
3. Local tissue damage
a. Skin
b. Gonads
c. Eyes
4. Shortening of life span
5. Genetic damage
EFFECTS OF FETAL IRRADIATION
Prenatal death
2. Neonatal death
3. Congenital malformation
4. Childhood malignancy
5. Diminished growth and development
Purpose Of Radiation Protection
The principle purpose of radiation protection are
To minimize patient exposure in medical diagnostic radiology
To ensure adequate protection of person operating or using x ray equipment.(Radiologist, Medical Imaging Technologist, Radiographer)
To ensure adequate protection of the general public in the vicinity areas where diagnostic procedure are in progress.
The three fundamental principles of radiation protection of patients are
Justification
Optimisation
The application of Dose Limit
The International Commission on Radiological Protection (ICRP) is responsible for the development of these principles.
Justification
The justification principle is anecdotally known as the benefit vs risk principle; that is, an individual's exposure to medical radiation should always have a greater benefit to the patient as to outweigh the negative consequences of the proposed examination. For example, the benefit in requesting a CT brain for a patient that has suffered significant head trauma generally outweighs any negative outcomes associated with that radiation exposure.
If the exposure has no justification then it should be avoided regardless of how small the dose might be.
This document discusses the importance of risk-benefit dialogue in medical imaging involving radiation. It provides background on radiation types, doses, and risks, as well as concepts like justification and optimization of radiation exposure. The document emphasizes that while individual radiation risk is generally low, large numbers of medical imaging exams warrant discussion of risks and benefits. It explores approaches for radiation risk communication, comparing dose to natural exposure or other activities. Overall, the document stresses the ethical need for healthcare providers to optimize the risk-benefit ratio when using medical imaging involving radiation.
The purpose of radiation protection is to provide an appropriate level of protection for humans without unduly limiting the beneficial actions giving rise to radiation exposure. Radiation protection is to prevent the occurrence of harmful deterministic effects and to reduce the probability of occurrence of stochastic effects (e.g. cancer and hereditary effects).The ICRP recommends, develops and maintains the International System of Radiological Protection, based on evaluation of the large body of scientific studies available to equate risk to received dose levels. The system's health objectives are "to manage and control exposures to ionising radiation so that deterministic effects are prevented, and the risks of stochastic effects are reduced to the extent reasonably achievable The ICRP's recommendations flow down to national and regional regulators, which have the opportunity to incorporate them into their own law; this process is shown in the accompanying block diagram. In most countries a national regulatory authority works towards ensuring a secure radiation environment in society by setting dose limitation requirements that are generally based on the recommendations of the ICRP.There are three basic principles of radiation protection: justification, optimization, and dose limitation. Justification involves an appreciation for the benefits and risks of using radiation for procedures or treatments. Physicians, surgeons, and radiologic personnel all play a key role in educating patients on the potential adverse effects of radiation exposure. The benefits of exposure should be well known and accepted by the medical community. Often, procedures that expose patients to relatively higher doses of radiation—for example, interventional vascular procedures—are medically necessary, and thus the benefits outweigh the risks. The As Low as Reasonably Achievable (ALARA) principle, defined by the code of federal regulations, was created to ensure that all measures to reduce radiation exposure have been taken while acknowledging that radiation is an integral part of diagnosing and treating patients. Any amount of radiation exposure will increase the risk of stochastic effects, namely the chances of developing malignancy following radiation exposure. These effects are thought to occur as a linear model in which there is no specific threshold to predict whether or not malignancy will develop reliably. For these reasons, the radiologic community teaches protection practices under the ALARA principle.The duration of radiation exposure, distance from the radiation source, and physical shielding are the key facets in reducing exposure. The exposure duration can be minimized in several ways. When exposing a patient to radiation, the technician or physician should preplan the required images to avoid unnecessary and redundant exposure. Magnification significantly increases the exposure to the patient; therefore, magnification should be used judiciously and gently.
Lasers in orthodontics /certified fixed orthodontic courses by Indian dental...Indian dental academy
The document discusses the history and various uses of lasers in orthodontics. It describes how lasers were initially developed in the 1960s and were first used in orthodontics for applications like laser scanning, holography, and soft and hard tissue procedures. Specifically, it outlines how different laser types like carbon dioxide, neodymium, erbium, and diode lasers can be used for soft tissue procedures with benefits like reduced pain and bleeding. It also discusses how lasers have been explored for applications in orthodontics like caries prevention, welding of dental materials, and as an alternative to plaster models.
Doses and Risks in Diagnostic Radiology, Interventional Radiology and Cardiol...DrAyush Garg
This document reviews doses and risks from natural background radiation as well as medical sources of radiation including diagnostic radiology, interventional radiology/cardiology, and nuclear medicine. It provides details on dose levels from various natural sources and medical procedures. The highest medical doses come from interventional fluoroscopy which can exceed skin dose limits and increase risks. Nuclear medicine procedures generally have lower doses than interventional methods but higher than diagnostic radiology. Risks to both patients and medical staff are discussed.
This document discusses various diagnostic imaging techniques for the temporomandibular joint (TMJ), including transcranial, transpharyngeal, transorbital, and reverse Towne's views. It provides details on positioning the patient, directing the central ray, and exposure parameters for each view. Computed tomography and magnetic resonance imaging are also summarized as they allow visualization of bony structures and soft tissues like the disc. The advantages and disadvantages of CT and MRI are compared. Signs and symptoms of temporomandibular disorders that can be evaluated with these imaging techniques are listed at the end.
The temporomandibular joint (TMJ) connects the mandible to the temporal bone. It has several components: the mandibular condyle, articular surfaces of the temporal bone, articular disc, capsule, ligaments, and muscles. The condyle and articular disc articulate with the articular eminence of the temporal bone. The TMJ is innervated by the auriculotemporal and masseteric nerves and supplied by branches of the external carotid artery. Key functions include mastication and speech which are facilitated by the rotating and translational movements of the joint.
Saliva and salivary analysis is discussed. There are 3 pairs of major salivary glands - parotid, submandibular, and sublingual glands. Saliva contains water, electrolytes, enzymes, immunoglobulins and mucins. Its functions include lubrication, digestion, antimicrobial activity, remineralization and maintenance of oral health. Salivary flow and composition can be assessed through tests such as salivary pH, microbial counts, enzyme activity assays and calcium dissolution tests to evaluate oral health status and risk of dental caries. Abnormal salivary function like hyposalivation or hypersalivation can have oral health implications.
This document provides an overview of urine analysis in dentistry. It discusses the processes of urine formation, reasons for performing urinalysis, sample collection methods, and the components evaluated in a urinalysis. Physical examination assesses volume, color, odor, turbidity, pH, and specific gravity. Biochemical examination tests for proteins, sugars, ketone bodies, bile, and blood. Microscopic tests identify cells, crystals, casts, and microorganisms. Together these evaluations can help diagnose and monitor diseases affecting the kidneys, urinary tract, and other body systems.
This document provides information about virus structure and classification. It begins with the history of virology and defines viruses. It describes the differences between bacteria and viruses, and between DNA and RNA viruses. It outlines the characteristics, structure, replication process, and reaction to physical and chemical agents of viruses. It discusses viral morphology, classification based on shape and presence of an envelope. It also covers bacteriophage structure and important human viruses classified by genome type and associated disease.
This document provides an overview of lasers in dentistry. It discusses the history and development of lasers, how lasers are designed and how laser light interacts with tissues. It describes common dental lasers like CO2 and argon lasers, and their applications. CO2 lasers are well absorbed in oral tissues and useful for soft tissue procedures. Argon lasers are absorbed by hemoglobin and melanin, making them good for coagulation. The document outlines the benefits of lasers for various dental procedures.
Lymph nodes of head and neck: Normal anatomy and applied aspectAshish Ranghani
Lymph nodes in the head and neck can be classified as either superficial or deep nodes. Superficial nodes include the submental, submandibular, buccal, mandibular, parotid, postauricular, occipital, anterior cervical, and superficial cervical nodes. Deep nodes include the prelaryngeal, pretracheal, paratracheal, jugulodigastric, and jugulo-omohyoid nodes. The lymph nodes drain various structures in the head and neck region and filter lymph before it returns to circulation. Lymph nodes are important for immune function and removing debris from tissues.
Lymph nodes of head & neck, Normal anatomy and its applied aspectAshish Ranghani
Lymph nodes in the head and neck can be classified as either superficial or deep nodes. Superficial nodes include the submental, submandibular, buccal, mandibular, parotid, postauricular, occipital, anterior cervical, and superficial cervical nodes. Deep nodes include the prelaryngeal, pretracheal, paratracheal, jugulodigastric, and jugulo-omohyoid nodes. The lymph nodes drain various structures in the head and neck region and filter lymph before it returns to circulation. Lymph nodes are important for immune function and removing debris from tissues.
Adhd Medication Shortage Uk - trinexpharmacy.comreignlana06
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Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
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share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
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Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
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Osteoporosis - Definition , Evaluation and Management .pdfJim Jacob Roy
Osteoporosis is an increasing cause of morbidity among the elderly.
In this document , a brief outline of osteoporosis is given , including the risk factors of osteoporosis fractures , the indications for testing bone mineral density and the management of osteoporosis
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Does Over-Masturbation Contribute to Chronic Prostatitis.pptxwalterHu5
In some case, your chronic prostatitis may be related to over-masturbation. Generally, natural medicine Diuretic and Anti-inflammatory Pill can help mee get a cure.
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Radiation as a friend or foe
1. RADIATION as
a friend or
foe
• ASHISH RANGHANI
• PG PART 2
• GDCH, AHMEDABAD
UNDER GUIDANCE OF
DR. J.S SHAH
PROFESSOR AND HEAD
ORAL MEDICINE AND RADIOLOGY
GDCH
DATE- 10/02/2017
2. CONTENTS
• Introduction
• Radiation and Types of Radiation
• Sources of Radiation
• Benefits And Risks of Radiation
• Uses of Electromagnetic waves
• Uses Of Radiation In Dentistry
• Radiotherapy
• Nuclear Medicine
• Types Of Radiation Effects
• Deterministic Effects
• Stochastic Effects
• Short Term Effects
• Long Term Effects
• In-utero Effects
• Radiation Effect On Cells
• General Effect Of Radiation
• Radiation Effect On Oral Cavity
3. DISCOVERY OF X-RADIATION
• Wilhelm Conrad Roentgen on
November 8, 1895 discovered x-rays
One of roentgen 1st experiments in
1895 was a film of his wife Bertha's
hand with a ring on her finger
4. • The first use of X rays was in medical diagnosis,
within six months of their discovery in 1895
• So a benefit from the use of radiation was
established very early on, but equally some of the
potential dangers of radiation became apparent in
the doctors who overexposed themselves to X rays
in the early 1900s.
5. What is radiation?....1,2
• Radiation refers to the propagation of energy
through space or a medium
• Ionizing radiation includes Gamma rays, X rays and
the radiation from radioactive materials.
• Non-ionizing radiation includes ultraviolet light,
radiant heat, radio waves and microwaves
6. Electromagnetic Spectrum1,2
• Gamma rays
• X – rays
• Ultraviolet
• Visible light
• Infra-red
• Microwaves
• Radio waves
Highest frequency
Shortest wavelength
Lowest frequency, Longest wavelength
8. Sources of ionizing radiation
Natural sources
• Cosmic rays
• Gamma rays from the
Earth
• Radon decay products
in the air
• Various radionuclides
found naturally in food
and drink
Artificial sources
• Medical X rays
• Fallout from the testing
of nuclear weapons in
the atmosphere
• Discharges of
radioactive waste from
the nuclear industry
• Industrial gamma rays
Radiation, people and environment, international atomic energy agency
9. source Dose (msv)
Nuclear industry
Uranium mining
Fuel fabrication
Nuclear reactors
Reprocessing
Medical uses
Radiology
Dentistry
Nuclear medicine
Radiotherapy
Industrial sources
Irradiation
Radiography
Isotope production
Luminizing
4.5
1.0
1.4
1.5
0.5
0.06
0.8
0.6
0.1
1.6
1.9
0.4
The average dose overall to
occupationally exposed workers
from artificial sources is less than
1 mSv in a year
Radiation, people and environment, international atomic energy agency
10. Benefits and risks
• The discovery of ionizing radiation and radioactive
materials has led to dramatic advances in medical
diagnosis and treatment, and they are used for a
wide range of procedures in industry, agriculture,
and research.
• They can be harmful to human beings, and people
must be protected from unnecessary or excessive
exposures.
Radiation, people and environment, international atomic energy agency
12. USES OF GAMMA RAYS 6
• Gamma rays kill
microbes, and are used
to sterilise food so that it
will keep fresh for longer.
This is known as
"irradiated" food
Gamma rays are also used to
sterilise medical equipment
Sterilization of plastic
syringes, hypodermic needles,
scalpels, surgical blades and
adhesive dressings & sutures
Gamma rays are the highest energy electromagnetic wave.
13. Gamma sterilization of human
tissue grafts
In industry, radioactive "tracer" substances can be put
into pipes and machinery, then we can detect where the
substances go
Study the nucleus in atoms
14. Ultraviolet Waves 6
• UV Light that is at a higher frequency and energy than violet light
• The main source of ultra-violet radiation is sunlight
• UV light can kill micro-organisms
• Ultra-violet radiation is used in hospitals to sterilize the surgical instruments and
operating theatres as it kills bacteria and viruses
• Too much exposure can cause:
• Sunburn and skin cancer
• As it damages cell DNA
15. Infra-red waves 6
• Infrared waves are heat waves
• Night vision goggles detect infrared
waves and allow the user to see the
movement of objects in the dark.
• Many TV remotes use infrared
• It shows a thermo-detector which is
placed outside hospitals/airport to
identify the warm and cool parts of a
person by analyzing infra-red radiation
emitted from the person’s body. And
through this we can see if someone is
having a fever
• For navigation through fog & haze as
it is less easily scattered compared to
visible light
16. Microwaves6
• One of their most common
uses is in microwave ovens.
• Other uses of microwaves:
• Radar communication
• Analysis of fine details of
molecular and atomic
structure
• Telephone communication
(mobile phones, etc)
17. Why are Radio Waves Important?6
The biggest use for radio
waves are communication,
such as phones, texts,
emails and instant
messaging.
Radio waves, that we use
every day. Such as-
• Television
• Wireless networks
• Mobile phones
• GPS systems
• Police radios
• Radio controlled toys
18. Dental uses of radiation
• Ionizing radiation has two very different uses in
dentistry — for diagnosis and therapy
• X-rays plays a vital role in the practice of dentistry
1. As part of routine examination,
2. Diagnostic purpose,
3. Treatment planning or for follow-up evaluation of
the patients
• Much higher doses are required to treat malignant
diseases in combination with other forms of
treatment.
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
19. Diagnostic radiology
• Radiographs are important in the routine investigation of dental
caries and its sequelae,
• Evaluation of periodontal diseases,
• Identification of osseous pathologies such as cysts and tumors
• Evaluation of traumatic injuries involving the jaws and facial
bones
• Radiographs are also useful in the evaluation of growth and
development
• From the foregoing it is very clear that radiographs are
sometimes referred to as the main diagnostic aids of the
clinician
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
20. DENTAL CARIES
• Intraoral radiography can reveal caries
lesions that otherwise might go
undetected, especially in case of proximal
lesions
• Various radiographs for caries detection:
• Bitewing: Aids in detecting caries in
interproximal areas and distal ends of
premolars and molars, and caries at CE
junction.
• Periapical: Aids in detecting gross carious
lesions, root caries and changes in the
apical and inter radicular bone due to
caries.
• OPG: Useful to examine a case with
multiple carious teeth or rampant caries.
21. Radiographic Assessment of Periodontal Conditions
Radiographs are especially helpful in the
evaluation of the following features:
• Amount of bone present
• Condition of the alveolar crests
• Bone loss in the furcation areas
• Width of the periodontal ligament space
• Poorly contoured or overextended
restorations
• Root length and morphology and the
crown-to-root ratio
• Open interproximal contacts, which may
be sites for food impaction
22. Inflammatory lesions of the jaws
• Periapical
inflammatory
lesions associated
with a mandibular
first molar
Occlusal film
demonstrates
chronic phase of
osteomyelitis
Panoramic film reveals
large sequestra (black
arrow) and a periosteal
reaction at the
inferior border of the
mandible in a case of
chronic osteomyelitis
23. Cysts of Jaw
Dentigerous cyst that is
expanding distally from
the involved third molar
Radicular Cyst
24. Benign Tumors of the Jaws
• Radiologic examination will
provide information regarding
the extent of the lesion, and
sometimes the characteristics are
so specific that a preliminary
diagnosis of the type of benign
tumor can be made
25. Malignant Diseases of the Jaws
• There are various diagnostic imaging modalities available to aid in
the diagnosis.
• Intraoral radiographs still provide the best image resolution and are
able to reveal malignant changes
• Panoramic radiographs provide an overall assessment of the
maxillofacial osseous structures and can reveal relevant changes such
as destruction of the boundaries of the maxillary sinus.
• Computed tomography (CT) images can provide a superior three-
dimensional analysis of the osseous structures and better determine
the position and extent of the tumor
• Positron emission tomographic (PET) scans, a technique capable of
detecting abnormal cellular metabolic activity associated with
malignant tumors, have been fused with CT images to provide an
accurate location of the tumor in preparation for radiotherapy.
• Magnetic resonance imaging (MRI) has provided three-dimensional
soft tissue images of tumors and information regarding perineural
spread and involvement of lymph nodes
26. • The purposes of TMJ imaging
are to evaluate the integrity
and relationships of the hard
and soft tissues, confirm the
extent or stage of progression
of known disease, and
evaluate the effects of
treatment
27. Trauma to Teeth and Facial Structures
• Radiologic examination is
essential for evaluating trauma
to the teeth and jaws.
• The presence, location, and
orientation of fracture planes
and fragments can be
determined, and the involvement
of nearby vital anatomic
structures can be assessed.
• Furthermore, foreign objects that
have become embedded within
the soft tissues as a result of
trauma can be detected.
28. SIALOGRAPHY
• Sialography is the radiographic
visualization of the salivary gland
following retrograde instillation of
soluble contrast material into the
ducts before imaging with plain
films, fluoroscopy, panoramic
radiography, CT
• Iodine which is used as a contrast
media
CONTRAST MEDIA
Two types of contrast media are presently available for contrast studies
Water soluble- Sinografin
Oil based- Ethiodol
29. Arthrography
• Arthrography is a technique
in which an indirect image of
the disk is obtained by
injecting a radiopaque
contrast agent into the joint
spaces under fluoroscopic
guidance.
• Magnetic resonance imaging
(MRI) has replaced
arthrography and is now the
imaging technique of choice
for the soft tissues of the
TMJ
30. SCINTIGRAPHY (Nuclear medicine)
• Scintigraphy with technetium (Tc) 99m is a dynamic and
minimally invasive diagnostic test to assess salivary gland
function and to determine abnormalities in gland uptake
and excretion
• Technetium is a pure gamma ray– emitting radionuclide
that is taken up by the salivary glands
• It has also been used to aid in the diagnosis of ductal
obstruction, sialolithiasis, gland aplasia and Sjögren’s
syndrome
31. • Salivary imaging is performed following the
injection of Tc 99m pertechnetate
• The uptake, concentration, and excretion of the
pertechnetate by the major salivary glands and
other organs is imaged with a gamma detector that
records both the number and the location of
gamma particles released in a given field during a
period of time
• A special detector called a gamma camera is used
to observe how the organs or tissue behave or how
quickly the radionuclide moves
32. Scintigraphy, 99m Tc-
pertechnetate
scan of the salivary glands (right
and left anterior oblique views)
demonstrates increased uptake of
radioisotope in the right parotid
gland (black arrowhead)
Scintigram taken after
administration
of a sialogog (lemon juice)
demonstrates
retention of isotope in right
parotid gland (white arrowheads).
This is a typical presentation of
salivary stasis
33. OBJECT LOCALIZATION
Two Dimensional Techniques
• Tube Shift Technique / Clark`s Technique
• Occlusal Radiography
• Right Angle Technique / Miller`s Technique
Three Dimensional Techniques
• Computed Tomography Scan (CT)
• CBCT ( Cone Beam Computed Tomography)
Frenny karjodkar, Text book of oral radiology. 2nd edition.
Methods Used to Localize Objects
34. Interpretation
When the dental structure or object seen in the second
radiograph appears to have moved in the same direction as
the shift of the position indicating device (PID), the structure
or the object in question is said to be positioned lingually.
But, if the object appears to have moved in a direction
opposite to the shift of the PID, then the object in question
is said to be positioned buccally.
SLOB rule: Same side Lingual - Opposite side Buccal.
Frenny karjodkar, Text book of oral radiology. 2nd edition.
35. Right angle technique
• Here two projections are taken at right angles to
each other, which helps to localize an object in the
maxilla or mandible.
Frenny karjodkar, Text book of oral radiology. 2nd edition.
Method
• A periapical radiograph is taken to show the position of
the object superio-inferiorly and anteroposteriorly.
• Next, an occlusal radiograph is taken which will show
the object’s buccolingual and anteroposterior
relationship.
36. A. The object appears to be located in
bone on the periapical radiograph.
B. The occlusal radiograph reveals
that the object is actually located
in the soft tissue lingual to the
mandible
Frenny karjodkar, Text book of oral radiology. 2nd edition.
37. Occlusal Radiography
• Locate roots and
supernumerary, unerupted,
and impacted teeth
• Stones in the ducts of
sublingual and
submandibular glands
• To determine the medial
and lateral extent of
disease
• Fractures of the mandible
and maxilla
38. ASSESSMENT OF FOLLOWING ANATOMIC PARAMETERS ON
RADIOGRAPHS
• Height of the alveolar bone
• Buccolingual dimension of the ridge at the implant
site
• Determine bone quality
• Determine long axis of alveolar bone
• Determine Jaw boundaries
• Pathology detection
• Position of inferior alveolar canal
Dental Implants
39. • periapical radiograph of
two successful dental
implants
• The close apposition of
the bone to the surface
of each implant.
Periapical radiograph of
bone loss around a root-
form dental implant (thin
radiolucent band
surrounding the implant),
indicating
failure of osseous
integration.
Periapical view of a
fractured endosseous
implant
40. What is Radiotherapy ?
• It is the medical use of ionizing radiation, generally
as part of cancer treatment to control or kill
malignant cells by destroying reproductive integrity
of the malignant cells.
• Radiotherapy can be given as
1. External radiotherapy (Teletherapy)
2. Internal radiotherapy (Brachytherapy)
Head and Neck Cancer Treatment, RadiologyInfo.org Reviewed: Mar-21-2016
41. • Head and neck cancer represents the 6th most
common malignancy & accounts for approx. 6% of
new cancer cases annually worldwide.
• The first patient was treated with radiation in 1896,
two months after the discovery of the X-ray.
Head and Neck Cancer Treatment, RadiologyInfo.org Reviewed: Mar-21-2016
42. • Patients with early-stage head and neck cancers are
treated with one modality—either radiation
therapy or surgery.
• Patients who have more extensive cancers are
often treated with chemotherapy and radiation
therapy.
• Sometimes, patients are treated with surgery
followed by postoperative radiation therapy and
chemotherapy
Head and Neck Cancer Treatment, RadiologyInfo.org Reviewed: Mar-21-2016
43. Intensity-modulated radiation therapy (IMRT)
• An advanced mode of high-precision radiotherapy
that utilizes computer-controlled x-ray accelerators
to deliver precise radiation doses to a malignant
tumor or specific areas within the tumor.
• The radiation dose is designed to confirm to the
three-dimensional (3-D) shape of the tumor by
modulating—or controlling—the intensity of the
radiation beam to focus a higher radiation dose to
the tumor while minimizing radiation exposure to
healthy cells
Head and Neck Cancer Treatment, RadiologyInfo.org Reviewed: Mar-21-2016
44. External beam therapy (EBT)
• A method for delivering a beam of high-energy x-rays to
the location of the tumor.
• The beam is generated outside the patient usually by a
linear accelerator targeted at the tumor site.
• These x-rays can destroy the cancer cells and careful
treatment planning allows the surrounding normal
tissues to be spared.
• No radioactive sources are placed inside the patient's
body.
Head and Neck Cancer Treatment, RadiologyInfo.org Reviewed: Mar-21-2016
45.
46. Other Uses of X rays-
• Examination of Baggage in Airports :
The use of X-rays in airports to
examine for the presence of
dangerous weapons or bombs is a
routine practice
• Industrial Use
• X-rays reveal structural information
about the material
• It can therefore be used to detect
structural deficits or cracks in metal
objects that are likely to be missed
by the human eye
47. Study the crystal structure of
crystalline substances
Examination and analysis of paintings, where
studies can reveal such details as the age of a
painting and underlying brushstroke
techniques that help to identify or verify the
artist
48. Health Concerns
• The widespread use of x-rays led to serious
injuries.
• Some early experimenters did tie x-ray exposure
and skin burns together.
49. How do X-rays cause damage?
• Two main mechanisms are thought to be
responsible:
• Direct damage to specific targets within the cell
• Indirect damage to the cell as a result of the
ionization
of water or other molecules within the cell.
• The first warning of possible adverse effects of x-
rays came from Thomas Edison, William J Morton,
and Nikola Tesla who each reported eye irritations
from experimentation with x-rays and fluorescent
substances.
50. Deterministic effects
• Nonstochastic effects (deterministic effects) are somatic
effects that have a threshold and that increase in severity
with increasing absorbed dose.
• Examples of nonstochastic effects include erythema, loss of
hair, cataract formation, and decreased fertility.
• Compared with stochastic effects, deterministic effects
require larger radiation doses to cause serious impairment
of health.
Eric Whaites.Essentials of Dental Radiography and Radiology.4th edition
51. Stochastic effects
• Their development is random and depends on the laws of chance or
probability. Examples of somatic stochastic effects include leukaemia
and certain tumours.
• These damaging effects may be induced when the body is exposed to
any dose of radiation.
• There is no threshold dose, and that every exposure to ionizing
radiation carries with the possibility of inducing a stochastic effect.
Eric Whaites.Essentials of Dental Radiography and Radiology.4th edition
52.
53. Short-Term Effects
• Following the latent period, effects that are seen within
minutes, days, or weeks are termed short-term effects.
Short-term effects are associated with large amounts of
radiation absorbed in a short time (e.g., exposure to a
nuclear accident or the atomic bomb).
• Acute radiation syndrome (ARS) is a short-term effect and
includes nausea, vomiting, diarrhea, hair loss, and
hemorrhage.
• Short-term effects are not applicable to dentistry.
Eric Whaites.Essentials of Dental Radiography and Radiology.4th edition
54. Long-term effects
• Effects that appear after years, decades, or generations are
termed long-term effects.
• Long-term effects are associated with small amounts of
radiation absorbed repeatedly over a long period.
• Repeated low levels of radiation exposure are linked to the
induction of cancer, birth abnormalities, and genetic
defects.
Eric Whaites. Essentials of Dental Radiography and Radiology.4th edition
55.
56. BIOLOGICAL EFFECTS
EFFECT ON CELLS
1.DNA
2.CYTOPLASM
3.NUCLEUS
4.CHROMOSOMES
GENERAL EFFECT OF
RADIATION
1.SKIN
2.BONE MARROW
3.Testicles
4.GONADAL
5.EYE
EFFECT ON ORAL TISSUES
1.ORAL MUCOSA-MUCOSITIS
2.TASTE BUDS
3.SALVARY GLANDS-
4.TEETH
5. RADIATION CARIES
6.BONES
7. MUSCULATURE
EFFECT ON WHOLE BODY
1.ACUTE RADIATION SYNDROME
57. CYTOPLASM
Increased permeability of plasma membrane to sodium
and potassium ions.
Swelling and disorganization of mitochondria.
Focal cytoplasmic necrosis.
58. NUCLEUS
• Nucleus is more radiosesitive than the cytoplasm
• Inhibition of cell division
59. Chromosome Aberrations
If radiation exposure
occurs after DNA synthesis
(I,e G2 or late s)only one
arm of the effected
chromosome is broken
If radiation occurs before
DNA synthesis (G1 or early
S) both arms are effected
60. The survivors of the atomic
bombings of Hiroshima and
Nagasaki have
demonstrated chromosome
aberrations in circulating
lymphocytes more than
two decades after the
radiation exposure.
62. SKIN
Physical foundations of radiology, Otto glasser, Third edition
Doses up to 1000 R or so given within a
few days leave little or no permanent
mark
Two or three times this amount may
leave permanent tanning and some
superficial blood vessel damage
Hair loss may be permanent and some
sweat gland destroyed
Hair loss
63. Skin: The reaction of the skin to radiation may be categorized as:
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
Early or acute signs
• Increased susceptibility to
chapping
• Intolerance to surgical
scrub
• Blunting and leveling of
finger ridges
• Brittleness and ridging of
finger nails
Late or chronic signs:
• Loosening of hair and
epilation
• Dryness and atrophy of skin,
due to destruction of the
sweat glands
• Progressive pigmentation,
telangiectasis and keratosis
• Indolent type of ulcerations
• Possibility of malignant
changes in tissue
64. • Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
HEMATOPOIETIC
INJURY
The usual picture of blood reaction to
radiation is leukopenia, which in some cases
may progress to leukemia, anemia,
lymphopenia, and loss of specific immune
response
The primary somatic risk from dental
radiography is leukemia induction, especially
in young individuals.
This is because at birth all bones contain
only red bone marrow. younger individuals
are at a greater risk of developing leukemia.
65. Eyes
• Epilation of eyelashes
• Inflammation, fibrosis and decreased flexibility
of the eyelid
• Damage to the lacrimal glands, leading to
dryness
• Ulceration of the cornea
• Initiation of cataract formation from the
periphery towards the center
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
66. Testicles
• Permanent sterility may be produced by acute dose
of 500 r to the reproductive organs
• Suppression of germinal activity
• Alteration in fertility
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
67. ORAL MUCOUS MEMBRANE
• The oral mucous membrane
contains a basal layer
composed of rapidly dividing,
radiosensitive stem cells.
• Near the end of the second
week of therapy, as some of
these cells die, the mucous
membranes begin to show
areas of redness and
inflammation (mucositis).
• Oral Radiology-Principles and Interpretation, White
and pharoh-6th Edition
68. • As then therapy continues, the
irradiated mucous membrane begins
to separate from the underlying
connective tissue, with the formation
of a white to yellow
pseudomembrane (the desquamated
epithelial layer).
• At the end of therapy the mucositis is
usually most severe, discomfort is at
a maximum, and food intake is
difficult.
• Oral Radiology-Principles and Interpretation, White
and pharoh-6th Edition
69. Taste Buds
• Taste buds are sensitive to radiation.
• Patients often notice a loss of taste
acuity during the second or third
week of radiotherapy.
• Bitter and acid flavors are more
severely affected when the posterior
two thirds of the tongue is irradiated
and salt and sweet when the anterior
third of the tongue is irradiated.
• Taste loss is reversible and recovery
takes 60 to 120 days
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
70. SALIVARY GLANDS
• The parenchymal component
of the gland is sensitive to
radiation. The gland
demonstrates progressive
fibrosis adiposis, loss of fine
vasculature and simultaneous
parenchymal degeneration.
• Parotid gland is more radio
sensitive than the other glands
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
71. • There is marked decrease in the salivary flow.
• The composition of saliva is affected.
• There is increased concentration of sodium,chloride,
calcium, magnesium ions and proteins.
• The saliva loses its lubricating properties.
• The mouth becomes dry and tender due to xerostomia.
• The pH of saliva is decreased which may initiate
decalcification of enamel.
• A compensatory hypertrophy of the salivary gland may
take place and the xerostomia may subside after six to
twelve months after therapy.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
72. Teeth
Exposure
Before calcification
completion - tooth bud may
be damaged
• At later stage of
development - may
arrest growth
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
Pulp shows decrease in vascular elements, with accompanying
fibrosis and atrophy
Pulpal response to infection, trauma, and various dental
procedures appears compromised
73. • Children receiving radiation therapy to the jaws may show
defects in the permanent dentition such as retarded root
development, dwarfed teeth, or failure to form one or
more teeth
• Eruptive mechanism of teeth is relatively radiation
resistant
• Adult teeth are resistant to the direct effects of radiation
exposure
• Radiation has no direct effect on the crystalline structure
of enamel, dentin, or cementum, and radiation does not
increase their solubility.
74. RADIATION CARIES
• Radiation caries is a rampant form of dental decay that may
occur in individuals who receive a course of radiotherapy
that includes exposure of the salivary glands
• Patients receiving radiation therapy to oral structures have
increases in Streptococcus mutans,Lactobacillus, and
Candida .
• Caries results from changes in the salivary glands and saliva,
including
• Reduced flow,
• Decreased pH,
• Reduced buffering capacity,
• Increased viscosity, and altered flora.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
75. TYPES
• Clinically, three types of radiation caries exist.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
• The most common is
widespread
superficial lesions
attacking buccal,
occlusal, incisal, and
palatal surfaces
• Another type
involves primarily
the cementum and
dentin in the cervical
region.
• These lesions may
progress around the
teeth
circumferentially
and result in loss of
the crown
• A final type appears
as a dark
pigmentation of the
entire crown. The
incisal edges may be
markedly worn
76. Radiation has a rapid effect on the
salivary glands
• In the first two weeks,
with a cumulative RT
dose of 20 Gy, around
80% of salivary function
is lost
• Above 58 Gy there was
a complete loss of
salivary gland function
77. Bone
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
Radiation acts by destroying
osteoblasts and to a lesser extent
osteoclasts
Subsequent to irradiation, Normal marrow may be
replaced with fatty marrow and fibrous connective
tissue.
The marrow tissue becomes hypo
vascular, hypoxic, and hypo cellular
78. • Osteoradionecrosis is the most serious clinical complication
that occurs in bone after irradiation.
• The decreased vascularity of the mandible renders it easily
infected by microorganisms from the oral cavity
• This bone infection may result from radiation-induced
breakdown of the oral mucous membrane, by tooth
extraction, a periodontal lesion, or from radiation caries
• This infection may cause a non healing wound in irradiated
bone
• It is more common in the mandible than in the maxilla,
probably because of the richer vascular supply to the
maxilla and the fact that the mandible is more frequently
irradiated
• The higher the radiation dose absorbed by the bone, the
greater the risk for osteoradionecrosis.
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
79. Musculature
• Restriction in mouth opening usually starts about 2 months after
radiotherapy is completed and progresses thereafter
• An exercise program may be helpful in increasing opening distance.
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
Radiation may causes inflammation and fibrosis
resulting in contracture and trismus in the
muscles of mastication
Usually the masseter or pterygoid muscles are
involved.
81. ACUTE RADIATION SYNDROME
Acute Radiation Syndrome (ARS) is an acute illness caused
by irradiation of the entire body (or most of the body) by a
high dose of penetrating radiation in a very short period of
time (usually a matter of minutes)
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
82. Acute Radiation Syndrome
• Oral Radiology-Principles and Interpretation, White and pharoh-6th Edition
DOSE (Gy) MANIFESTATION
1 to 2 Prodromal symptoms
2 to 4 Mild hematopoietic symptoms
4 to 7 Severe hematopoietic symptoms
7 to 15 Gastrointestinal symptoms
>50 Cardiovascular and central nervous system symptoms
83. STAGES OF ARS
• Prodromal stage (N-V-D stage): The classic
symptoms for this stage are nausea, vomiting,
as well as anorexia and possibly diarrhea
(depending on dose), which occur from
minutes to days following exposure. The
symptoms may last (episodically) for minutes
up to several days
• Latent stage: In this stage, the patient looks
and feels generally healthy for a few hours or
even up to a few weeks
• Manifest illness stage: In this stage the
symptoms depend on the specific syndrome
and last from hours up to several months
• Recovery or death: Most patients who do not
recover will die within several months of
exposure. The recovery process lasts from
several weeks up to two years
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
84. Bone marrow (hemopoietic) syndrome:
• (2 to7 Gy) Here severe damage may be caused to the circulatory
system.
• The bone marrow being radiosensitive, results in fall in the
number of granulocytes, platelets and erythrocytes.
• Granulocytes, with short lives in circulation, fall off in a few days,
whereas red blood cells, with long lives in circulation, fall off
slowly
• Clinically this is manifested as lymphopenia, granulocytopenia and
hemorrhage due to thrombocytopenia and anemia due to
depletion of the erythrocytes.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
85. GASTROINTESTINAL SYNDROME
• The gastrointestinal syndrome is caused by whole-body
exposures in the range of 7 to 15 Gy, which causes
extensive damage to the gastrointestinal system in
addition to the hematopoietic damage described
previously
• Because of the denuded mucosal surface, there is loss
of plasma and electrolytes, loss of efficient intestinal
absorption, and ulceration of the mucosal lining with
hemorrhaging into the intestines
• These changes are responsible for the diarrhea,
dehydration, and loss of weight
• Endogenous intestinal bacteria readily invade the
denuded surface, producing septicemia
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
86. • At about the time that developing damage to the
gastrointestinal system reaches a maximum, the effect of
bone marrow depression is beginning to be manifested.
• The result is a marked lowering of the body ’s defense
against bacterial infection and a decrease in effectiveness of
the clotting mechanism.
• The combined effects of damage to these hematopoietic
and gastrointestinal stem cell systems cause death within 2
weeks from fluid and electrolyte loss, infection, and possibly
nutritional impairment.
• Thirty of the firefighters at the accident site at Chernobyl,
Ukraine, died in the first few months of the hematopoietic
or gastrointestinal syndrome
87. Cardiovascular and central nervous system
syndrome
• (More than 50 Gy): This produces death within one or two
days.
• Individuals show incordination, disorientation and
convulsions suggestive of extensive damage to the nervous
system.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
88. Effects on the unborn child
• Embryos and fetuses are considerably more radio-sensitive than
adults because most embryonic cells are relatively undifferentiated
and rapidly mitotic
• The developing fetus is particularly sensitive to the effects of
radiation, especially during the period of organogenesis (2–9 weeks
after conception).
• These effects are deterministic in nature
• Exposures in the range of 2 to 3 Gy during the first few days after
conception are thought to cause undetectable death of the embryo.
• The period of maximal sensitivity of the brain is 8 to 15 weeks after
conception.
• Essentials of Oral and maxillofacial radiology, Freny R Karjodkar
89. • The major problems are:
1.Congenital abnormalities or death associated with
large doses of radiation
2.Mental retardation associated with low doses of
radiation.
There is also an Increased risk for childhood cancer,
(leukemia and solid tumors), after irradiation in
utero.
90. X-ray examination Estimated risk
of fatal cancer
Dental intraoral (x 2) 1 in 2 000 000
Dental panoramic
tomograph
1 in 2 000 000
Skull (PA) 1 in 670 000
Skull (Lat) 1 in 2 000 000
Chest (PA) 1 in 1 000 000
CT chest 1 in 2500
CT head 1 in 10000
A broad estimate of the magnitude of
the risk of developing a fatal radiation-
induced cancer, from various X-ray
examinations, was published in the
UK in 1999 by the NRPB in their
booklet
Guidelines on Patient Dose to Promote the Optimisation of Protection for Diagnostic
Medical Exposures, 1999
91. Chernobyl accident
• Despite all the safety
measures applied in using
radiation and radioactive
materials, accidents can
happen
• An explosion in a nuclear
reactor at the Chernobyl
nuclear power plant on 26
April 1986 caused the release
of substantial quantities of
radionuclides during a period
of ten days
• As the contaminated air
spread throughout Europe
and beyond, local weather
conditions largely determined
Radiation, people and environment, international atomic energy agency
92. • The accident had a catastrophic effect locally and high
radiation exposures of emergency workers led to the
deaths of 31 people.
• The firemen received large external doses from
deposited radionuclides, between 3 and 16 Sv, and
contamination on their skin lead to severe erythema
• A further 209 people were hospitalized of whom 106
were diagnosed as having acute radiation sickness
• The most significant radionuclides were iodine-131,
caesium-134 and caesium-137
93. • Between 1945 and 1999 there were some 140
serious reported accidents involving excessive
radiation exposure in the nuclear industry, military
facilities, hospitals, research facilities, and general
industry. The most frequent occurrence (about 70
in total) is the mishandling or misappropriation of
sealed sources used for radiography in industry and
radiotherapy in hospitals
Radiation, people and environment, international atomic energy agency
94. REFERENCES
1.White and pharoh-Oral Radiology-Principles and
Interpretation 6th
2.Essentials of Oral and maxillofacial radiology, Freny R
Karjodkar
3.Eric Whaites.Essentials of Dental Radiography and
Radiology.4th edition.
4. Physical foundations of radiology, Otto glasser, Third
edition
5. Head and Neck Cancer Treatment, RadiologyInfo.org
Reviewed: Mar-21-2016
6. Radiation, people and environment, international atomic
energy agency