This document discusses infection control in orthodontics. It describes the main pathways for cross-contamination between patients and dental staff, as well as the most important pathogens including hepatitis B virus, HIV, and herpes simplex virus. Proper sterilization of orthodontic instruments and use of personal protective equipment are essential to control cross-infection in the dental office.
K- Sir loop /certified fixed orthodontic courses by Indian dental academy Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
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
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
Traditional begg philosophy /certified fixed orthodontic courses by Indian ...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.
Indian dental academy provides dental crown &
Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit
www.indiandentalacademy.com ,or call
0091-9248678078
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
Andrew’s straight wire appliance /certified fixed orthodontic courses by Indi...Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
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
This document provides an overview of pitchfork analysis for evaluating changes in cephalometric radiographs over time. It discusses landmarks used for superimposing tracings of the cranial base, maxilla, and mandible. For the cranial base, sella and nasion are commonly used. The maxilla can be superimposed along the palatal plane or contours of the zygomatic arches. For the mandible, the lower border, symphysis, or gonion-gnathion and gonion-menton planes are used. Pitchfork analysis expresses changes in molar and incisor relationships algebraically to quantify treatment effects.
K- Sir loop /certified fixed orthodontic courses by Indian dental academy Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
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
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
Traditional begg philosophy /certified fixed orthodontic courses by Indian ...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.
Indian dental academy provides dental crown &
Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit
www.indiandentalacademy.com ,or call
0091-9248678078
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
Andrew’s straight wire appliance /certified fixed orthodontic courses by Indi...Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
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
This document provides an overview of pitchfork analysis for evaluating changes in cephalometric radiographs over time. It discusses landmarks used for superimposing tracings of the cranial base, maxilla, and mandible. For the cranial base, sella and nasion are commonly used. The maxilla can be superimposed along the palatal plane or contours of the zygomatic arches. For the mandible, the lower border, symphysis, or gonion-gnathion and gonion-menton planes are used. Pitchfork analysis expresses changes in molar and incisor relationships algebraically to quantify treatment effects.
in Orthodontics, Torque is a vital ingredient in the achievement of optimal esthetics, function and health of teeth and surrounding tissues, as also in stability of the treatment results
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
Dr. Percival Raymond Begg developed the Begg technique for orthodontic treatment over many years, beginning in the 1920s. He studied under Dr. Angle and was an early user of the Edgewise appliance. Through his own practice, Begg realized some limitations of Angle's methods and made modifications like removing teeth or stripping tooth width to improve outcomes. This evolved into the Begg technique using light wires and brackets to minimize forces and reduce relapse. The technique gained popularity after visits by American orthodontists to Begg's practice and demonstrations of its effectiveness.
Concepts of orthodontic bracket positioning techniques / fixed orthodontics c...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
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
Roth philosophy /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This document discusses the three orders of tooth movement that can be achieved through bending orthodontic archwires: first, second, and third order bends. First order bends move teeth inwards/outwards and can be used for derotation. Second order bends tip teeth vertically and are used for anchorage. Third order bends torque individual teeth by twisting the wire. Special pliers can help perform specific bends, like step pliers for first order bends and rose pliers for third order torque bends. Proper bending technique is important to avoid wire fractures.
This document discusses various types of intrusion arches used in orthodontics to correct deep overbites. It begins by defining intrusion and describing the biomechanics and principles involved. It then covers 9 specific intrusion arch designs: 1) Rickett's Utility Arch 2) Tipback Springs 3) Burstone's Continuous Intrusion Arch 4) Burstone's Three Piece Intrusion Arch 5) K-SIR 6) Connecticut Intrusion Arch 7) PG Retraction Spring 8) Translation Arch 9) Lingual Arch for intruding lower incisors. For each type, it provides details on materials, design, and mechanics of intrusion.
Roth philosophy /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This document discusses various types of orthodontic archwires. It begins by introducing orthodontic archwires and their purpose in generating forces to move teeth. It then describes several specific archwire materials: titanium niobium wire, which is soft and easy to form while maintaining strength; timolium titanium wire, which combines properties of nickel titanium and stainless steel; super cable, a superelastic nickel titanium coaxial wire; combined archwires that allow for tipping and translation; bioforce wire, which applies varying forces along the dental arch; and optiflex wire, a non-metallic wire made of clear optical fibers. Each wire type is discussed in terms of its properties, applications, advantages,
The document outlines a 16-part series on "Common Sense Mechanics" in orthodontics. It discusses various orthodontic mechanics principles like forces, moments, torque, and their clinical applications. Key topics include the diving board concept to control forces, differential torque mechanics, archwire-bracket relationships, extraction mechanics, and various malocclusion treatments. The goal is to help orthodontists understand and apply basic mechanics principles in a common sense manner.
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
This document discusses various methods and appliances for distalizing maxillary molars, including removable and fixed options. Removable appliances discussed include extraoral traction using headgear as well as removable appliances with finger springs or sliding jigs. Fixed appliances discussed include intramaxillary devices like Wilson's 3D appliance as well as intermaxillary appliances like Herbst or Jasper Jumper. Factors like the presence of second molars, skeletal pattern, and growth prognosis must be considered when determining whether molar distalization is indicated.
The document outlines the key anatomical landmarks and measurements used in Rakosi analysis to evaluate facial growth patterns and plan functional appliance therapy. The patient's analysis shows a vertical growth pattern with a posteriorly positioned mandible relative to the cranial base. Both the upper and lower incisors are proclined, making functional appliance therapy more challenging. Overall, the Rakosi analysis provides important diagnostic information but also indicates some limitations for treating this patient solely with a functional appliance due to the vertical growth pattern and proclined incisor positions.
determinate vs indeterminate force systemKumar Adarsh
This document discusses force systems in orthodontics. It describes determinate and indeterminate force systems, with determinate systems providing better control of forces and moments. One-couple systems are created using a cantilever spring or auxiliary arch wire tied to a tooth at one end. Two-couple systems are created when an arch wire is tied into brackets on both ends. Common applications of one and two-couple systems include intrusion/extrusion arches and lingual arches. Segmented arch mechanics allow precise control but require more wire bending compared to continuous arch wires.
Recent advances in orthodontic materials 8th ios-pgsc /certified fixed orth...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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
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
Twin block /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown &
Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit
www.indiandentalacademy.com ,or call
0091-9248678078
Temporo Mandibular joint (TMJ) importance in orthodontic treatment /certifie...Indian dental academy
Welcome to 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.
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
This document discusses the role of radiology in orthodontics. It describes various types of radiographs used, including intraoral radiographs like periapical and bitewing films, and extraoral radiographs like panoramic and cephalometric images. Newer 3D imaging techniques like cone beam CT, MRI, and laser holography are also covered. The document outlines the advantages and disadvantages of each radiographic method and their applications in orthodontic assessment, treatment planning, and monitoring of treatment.
Acute radiation syndrome /certified fixed orthodontic courses by Indian dent...Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
in Orthodontics, Torque is a vital ingredient in the achievement of optimal esthetics, function and health of teeth and surrounding tissues, as also in stability of the treatment results
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
Dr. Percival Raymond Begg developed the Begg technique for orthodontic treatment over many years, beginning in the 1920s. He studied under Dr. Angle and was an early user of the Edgewise appliance. Through his own practice, Begg realized some limitations of Angle's methods and made modifications like removing teeth or stripping tooth width to improve outcomes. This evolved into the Begg technique using light wires and brackets to minimize forces and reduce relapse. The technique gained popularity after visits by American orthodontists to Begg's practice and demonstrations of its effectiveness.
Concepts of orthodontic bracket positioning techniques / fixed orthodontics c...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
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
Roth philosophy /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This document discusses the three orders of tooth movement that can be achieved through bending orthodontic archwires: first, second, and third order bends. First order bends move teeth inwards/outwards and can be used for derotation. Second order bends tip teeth vertically and are used for anchorage. Third order bends torque individual teeth by twisting the wire. Special pliers can help perform specific bends, like step pliers for first order bends and rose pliers for third order torque bends. Proper bending technique is important to avoid wire fractures.
This document discusses various types of intrusion arches used in orthodontics to correct deep overbites. It begins by defining intrusion and describing the biomechanics and principles involved. It then covers 9 specific intrusion arch designs: 1) Rickett's Utility Arch 2) Tipback Springs 3) Burstone's Continuous Intrusion Arch 4) Burstone's Three Piece Intrusion Arch 5) K-SIR 6) Connecticut Intrusion Arch 7) PG Retraction Spring 8) Translation Arch 9) Lingual Arch for intruding lower incisors. For each type, it provides details on materials, design, and mechanics of intrusion.
Roth philosophy /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
This document discusses various types of orthodontic archwires. It begins by introducing orthodontic archwires and their purpose in generating forces to move teeth. It then describes several specific archwire materials: titanium niobium wire, which is soft and easy to form while maintaining strength; timolium titanium wire, which combines properties of nickel titanium and stainless steel; super cable, a superelastic nickel titanium coaxial wire; combined archwires that allow for tipping and translation; bioforce wire, which applies varying forces along the dental arch; and optiflex wire, a non-metallic wire made of clear optical fibers. Each wire type is discussed in terms of its properties, applications, advantages,
The document outlines a 16-part series on "Common Sense Mechanics" in orthodontics. It discusses various orthodontic mechanics principles like forces, moments, torque, and their clinical applications. Key topics include the diving board concept to control forces, differential torque mechanics, archwire-bracket relationships, extraction mechanics, and various malocclusion treatments. The goal is to help orthodontists understand and apply basic mechanics principles in a common sense manner.
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
This document discusses various methods and appliances for distalizing maxillary molars, including removable and fixed options. Removable appliances discussed include extraoral traction using headgear as well as removable appliances with finger springs or sliding jigs. Fixed appliances discussed include intramaxillary devices like Wilson's 3D appliance as well as intermaxillary appliances like Herbst or Jasper Jumper. Factors like the presence of second molars, skeletal pattern, and growth prognosis must be considered when determining whether molar distalization is indicated.
The document outlines the key anatomical landmarks and measurements used in Rakosi analysis to evaluate facial growth patterns and plan functional appliance therapy. The patient's analysis shows a vertical growth pattern with a posteriorly positioned mandible relative to the cranial base. Both the upper and lower incisors are proclined, making functional appliance therapy more challenging. Overall, the Rakosi analysis provides important diagnostic information but also indicates some limitations for treating this patient solely with a functional appliance due to the vertical growth pattern and proclined incisor positions.
determinate vs indeterminate force systemKumar Adarsh
This document discusses force systems in orthodontics. It describes determinate and indeterminate force systems, with determinate systems providing better control of forces and moments. One-couple systems are created using a cantilever spring or auxiliary arch wire tied to a tooth at one end. Two-couple systems are created when an arch wire is tied into brackets on both ends. Common applications of one and two-couple systems include intrusion/extrusion arches and lingual arches. Segmented arch mechanics allow precise control but require more wire bending compared to continuous arch wires.
Recent advances in orthodontic materials 8th ios-pgsc /certified fixed orth...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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
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
Twin block /certified fixed orthodontic courses by Indian dental academy 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.
Indian dental academy provides dental crown &
Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit
www.indiandentalacademy.com ,or call
0091-9248678078
Temporo Mandibular joint (TMJ) importance in orthodontic treatment /certifie...Indian dental academy
Welcome to 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.
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
This document discusses the role of radiology in orthodontics. It describes various types of radiographs used, including intraoral radiographs like periapical and bitewing films, and extraoral radiographs like panoramic and cephalometric images. Newer 3D imaging techniques like cone beam CT, MRI, and laser holography are also covered. The document outlines the advantages and disadvantages of each radiographic method and their applications in orthodontic assessment, treatment planning, and monitoring of treatment.
Acute radiation syndrome /certified fixed orthodontic courses by Indian dent...Indian dental academy
Welcome to 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.
Indian dental academy has a unique training program & curriculum that provides students with exceptional clinical skills and enabling them to return to their office with high level confidence and start treating patients
State of the art comprehensive training-Faculty of world wide repute &Very affordable.
Radiation is energy transmitted through space or matter in the form of waves or particles. It includes visible light, ultraviolet light from the sun, and radio/TV signals. Nuclear radiation comes from unstable atoms undergoing radioactive decay, emitting particles like alpha and beta or electromagnetic waves like gamma rays. Exposure to ionizing radiation can damage living tissue. Natural sources of radiation include cosmic rays, radioactive elements in the earth's crust like radon, and some food/drink. Medical procedures and occupational exposures also contribute. In materials, radiation can cause impurities from nuclear reactions, ionization by charged particles, and displacement of atoms from their normal positions in the crystal structure.
Dentists are exposed to a variety of occupational hazards including biological, physical, chemical, ergonomic and radiation hazards. Biological hazards include exposure to infectious diseases from patients through direct or indirect contact with bodily fluids. Physical hazards include injuries from sharp instruments. Chemical hazards stem from exposure to substances like mercury and latex. Prolonged awkward postures and repetitive motions can cause musculoskeletal disorders. Radiation exposure occurs from dental X-rays. Proper precautions like barriers, hygiene protocols, protective equipment, ergonomic practices and radiation monitoring can help prevent or minimize these occupational hazards for dentists.
This document provides a classification and descriptions of radiolucent and radiopaque lesions in the jaw bones. It categorizes lesions based on their appearance on radiographs as radiolucent or radiopaque, and whether they contact a tooth. Common radiolucent lesions described include periapical granulomas, cysts, and abscesses. Radiopaque lesions include cementomas, osteosclerosis, and tori. Mixed lesions involve calcified material within lesions. The document provides detailed information on diagnostic features and locations of various pathologies involving the jaw bones.
This document discusses dosimetry and radiation protection. It begins with a brief history of radiation discovery and the first radiograph. It then discusses key concepts in radiation protection including dose limits for different exposure groups, the ALARA (As Low As Reasonably Achievable) philosophy, and the basic methods of reducing radiation exposure through time, distance and shielding. The document also covers external and internal radiation sources, dose and exposure concepts, and methods for reducing radiation exposure in dental radiography through proper equipment selection, technique choice, processing and interpreting images. Protection of patients, personnel and the public is emphasized throughout.
Radiation hazards and infection control in orthodontics / fixed orthodontics ...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
Acute radiation syndrome 34 /certified fixed orthodontic courses by Indian de...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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
BIOLOGICAL EFFECTS OF Radiation IN DENTISTRY. ppt.pdfSamkeloKhumalo2
Radiation damage to tissue and/or organs depends on the dose of radiation received, or the absorbed dose which is expressed in a unit called the gray (Gy). The potential damage from an absorbed dose depends on the type of radiation and the sensitivity of the different tissues and organs.
EFFECT OF RADIATION ON HUMAN BODY ( IN DENTISTRY )Vibhor Tyagi
Radiation can be either particulate or electromagnetic. Particulate radiation includes alpha, beta, and neutron particles, while electromagnetic radiation includes radio waves, visible light, and gamma rays. Radiation is categorized as either ionizing or non-ionizing based on its ability to ionize atoms. Ionizing radiation like UV, X-rays, and gamma rays have enough energy to remove electrons from atoms. The effects of radiation can be deterministic, where severity depends on dose, or stochastic, where probability but not severity depends on dose. Radiation can cause direct DNA damage or indirect damage through production of free radicals in tissue. Different tissues have varying radiosensitivity, with blood, skin, and oral mucosa being highly sensitive. Ac
This document discusses the effects of radiation on oral tissues. It begins by explaining radiation chemistry and how radiation directly and indirectly damages biological molecules. It then discusses the deterministic effects of radiation on cells, tissues, and organs. Specific oral tissues that are discussed include the oral mucosa, salivary glands, teeth, bone, and the risks of oral complications like mucositis, xerostomia, and osteoradionecrosis. The document provides detailed information on the histological changes caused by radiation exposure in these oral structures.
1. Radiobiology is the study of the effects of ionizing radiation on biological tissues. DNA is the most sensitive structure affected, as it regulates cellular activity and contains genetic information.
2. Radiation can directly damage DNA molecules and other cellular components like RNA, enzymes, and proteins. However, most damage occurs indirectly when radiation interacts with water molecules within cells, producing ions and free radicals that then damage DNA.
3. The effects of radiation exposure depend on factors like radiation dose and the type of exposed cells. Somatic effects impact the exposed individual's health while genetic effects can impact future generations if reproductive cells are affected.
Radiology in orthodontics /certified fixed orthodontic courses by Indian dent...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.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
Radiology in orthodontics dr.kavitha /certified fixed orthodontic courses by ...Indian dental academy
This document discusses radiology techniques used in orthodontics. It begins with an introduction to radiation physics, including the production of x-rays and properties of x-rays. It then covers radiation biology and the effects of radiation on tissues. The document discusses various intraoral and extraoral radiographic techniques used in orthodontics, including periapical radiographs, bite wing radiographs, and lateral cephalograms. It provides details on techniques, uses, and interpretations of different types of radiographs.
radiation biology / dental implant courses by Indian dental academy 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
This document discusses ionizing radiation, its biological effects, and safety issues. It begins by defining ionizing radiation and its units of measurement. It then describes the mechanisms by which ionizing radiation can damage cells, particularly DNA, and potentially lead to genetic mutations and cancer initiation. Key factors that influence radiosensitivity, such as the cell cycle phase and tissue type, are also covered. The document discusses deterministic effects, which occur above threshold doses, and stochastic effects like cancer that occur probabilistically. Guidelines for radiation protection emphasize justification of exposures and optimizing procedures to minimize risks.
The document discusses the health effects of radiation exposure, including radiation sickness caused by changes to living tissues, as well as somatic and genetic effects. It describes the mechanisms by which ionizing radiation interacts with and damages biological molecules and cells, leading to both acute and long-term health consequences like cancer and genetic mutations. Guidelines are provided for radiation safety and protection measures to minimize exposure when working with radiation sources.
This document summarizes key concepts in radiobiology. It discusses how radiation can directly or indirectly damage biological molecules through ionization. Both deterministic and stochastic effects are covered, with deterministic referring to cell killing and stochastic to long-term effects like cancer. Specific radiation effects are outlined for DNA, chromosomes, tissues, and organs. The document also examines radiation effects on oral tissues, whole body irradiation, and heritable/stochastic effects like cancer formation.
This document discusses the effects of ionizing radiation on living systems. It begins by explaining radiation chemistry and the direct and indirect effects of radiation. It then discusses the deterministic and stochastic effects of radiation on cells and organs. Specific effects are described for oral tissues, including oral mucosa, salivary glands, taste buds, teeth and bone. The effects of whole body irradiation including acute radiation syndrome and effects on various organ systems are also summarized.
This document discusses the effects of ultraviolet (UV) radiation on the eyes. It begins by explaining what UV rays are and their sources like sunlight. Prolonged exposure to UV rays can cause physiological issues like sunburn, skin aging, and skin cancers. In the eyes, UV exposure is associated with conditions like pterygium, pinguecula, photokeratitis, cataract, age-related macular degeneration, and retinal damage. To help protect the eyes, the document recommends wearing sunglasses with UV protection, as well as blue light-blocking lenses.
Radiation causes damage to living tissues and can cause both somatic (harmful to the person) and genetic (reflected in offspring) effects. The main mechanisms of damage are ionization, where radiation forms ions that interact with matter, and indirect effects where radiation breaks water molecules which generate reactive radicals that damage cells. Early effects include radiation sickness, while later effects include increased risk of cancer and shortened lifespan. Principles of radiation safety include increasing distance from the source, limiting exposure time, and using protective barriers like lead aprons and gloves.
This document provides information on occupational radiation safety for radiologic technologists. It discusses the risks of ionizing radiation exposure and strategies to minimize that exposure through proper use of time, distance, and shielding techniques. Protective equipment discussed includes lead aprons, thyroid collars, gloves, glasses and face masks. The document emphasizes the importance of radiation safety given the increased risk of health issues like cataracts for those who work regularly with medical imaging that uses ionizing radiation.
Ionizing radiation can cause both deterministic and stochastic effects on the human body. Deterministic effects, such as radiation burns, occur above threshold doses and include skin damage, cataracts, sterility, and growth issues for children. Stochastic effects, like cancer induction, occur probabilistically with no safe threshold. The risk of cancer increases with radiation dose. Radiation protection principles aim to justify medical uses, optimize protection measures, and limit radiation doses. Attention to shielding, distance, equipment positioning, and monitoring can help reduce radiation exposures.
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 summarizes the effects of radiation therapy on oral tissues. Radiation is commonly used to treat oral cancers. It is delivered in small daily doses over 6-7 weeks for a total of 60-70 Gy. This causes damage to oral mucosa, taste buds, salivary glands, teeth, bone, and muscles. Oral mucositis is a common side effect, along with loss of taste, xerostomia, and rampant dental caries due to changes in saliva. Teeth may have arrested development. Long term risks include osteoradionecrosis and trismus. Management involves oral hygiene, pain control, fluoride application, and sometimes surgery.
Similar to Radiation hazards &infection control in orthodontics / orthodontic courses by indian dental academy (20)
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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
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This document discusses dental occlusion concepts and philosophies for complete dentures. It introduces key terms like physiologic occlusion and defines different occlusion schemes like balanced articulation and monoplane articulation. The document discusses advantages and disadvantages of using anatomic versus non-anatomic teeth for complete dentures. It also outlines requirements for maintaining denture stability, such as balanced occlusal contacts and control of horizontal forces. The goal of occlusion for complete dentures is to re-establish the homeostasis of the masticatory system disrupted by edentulism.
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This document discusses dental casting investment materials. It describes the three main types of investments - gypsum bonded, phosphate bonded, and ethyl silicate bonded investments. For gypsum bonded investments specifically, it details their classification, composition including the roles of gypsum, silica, and modifiers, setting time, normal and hygroscopic setting expansion, and thermal expansion. It provides information on how the properties of gypsum bonded investments are affected by their composition. The document serves as a comprehensive overview of dental casting investment materials.
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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
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How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
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Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
3. Introduction
X-rays are a form of electromagnetic radiation
Ability to ionize matterwhich is the initiating
event in radiation induced biologic changes
www.indiandentalacademy.com
4. RADIATION BIOLOGYRADIATION BIOLOGY
IS THE STUDY OF THE EFFECTS OF
IONIZING RADIATION ON THE LIVING
SYSTEM.
Deterministic Stochastic
Severity of response probability of a
proportional to dose response occur
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5. RADIATION CHEMISTRYRADIATION CHEMISTRY
Free radical production
RH + Photon R + H+
+ e
These free radicals are unstable ,short lived and highly
reactive.
Fate of the free radical _
1) Dissociation
R X + Y
2) Cross linking
R + S RS
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6. thus there is formation of structurally and
functionally biologic molecules differing from
original molecule.there by inducing biological
change.
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7. Radiation acts on living system either
DIRECT INDIRECT
Direct ionization of biologic photon absorbed by
H2O
macromolecules with H2O IONIZED
formation of unstable free
radicals. Resultant free
radical
interact and
change the
macro moleculewww.indiandentalacademy.com
8. Radiosensitvity and cell typeRadiosensitvity and cell type
Most radiosensitive cells are are
1)undergoing mitoses
2)having a high mitotic rate
3)are most primitive in differentiation
www.indiandentalacademy.com
9. Cells are usually divided into five categories of
radiosenstivity
1)vegetative inter mitotic cells
2)differentiating inter mitotic cells
3)multipotential connective tissue cells
4)reverting post mitotic cells
5)fixed post mitotic cells
www.indiandentalacademy.com
10. )vegetative intermitotic cells—most radiosensitive
Eg:precursor cell–
spermatogenicerythoblastic ,basal cells of the oral
mucous membrane.
2)differentiating intermitotic cells –Eg: intermediate
cells of hemapoietic ,replicating cells of the inner
enamel epithelium
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11. Multi potential connective tissue cells –
---Eg intermediate radio sensitivity
--- : endothelial cells,fibroblasts
Reverting post mitotic cells ---radio resistant
---Eg: acinar and ductal cells of salivary gland and
pancreas,parenchymal cells of liver ,kidney and
thyroid
Fixed post mitotic cells---most radioresistant
---Eg:neurons ,striated muscle cells ,squamous cells
close to the surface of oral mucous membrane and
erythocytes
www.indiandentalacademy.com
12. High Intermediate Low
Lymphoid Fine vasculature Optic lens
Bone marrow Growing cartilage Mature
Growing bone eryhtocytes
Intestines Salivary glands Muscle
Mucous Lungs cells
membrane Kidney Neurons
Liver
Relative Radio sensitivityRelative Radio sensitivity
of Various Organsof Various Organs
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14. Radiation effects may be spoken In terms :-
the short term effects which bring about …
mitosis linked cell death
the long term effects that bring about….fibro
atrophic cell death
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15. Short term effectsShort term effects
Primarily determined by the sensitivity of the
parenchymal cells of the respective
tissue
Raidly proliferatingcell loss mitosis linked
reduction in the number of mature cells .
In tissues that undergo little proliferation the
radiation induced hypoplasia is not evident
www.indiandentalacademy.com
16. Long Term EffectsLong Term Effects
Determined by the extent of damage to the
fine vasculature of the tissue
Endothelial cells---multi potential
connective tissue cells---intermediate radio
sensitivity..
Thus over a period of time ---capillaries
,degenerate and undergo necrosis.
Permeability increased
www.indiandentalacademy.com
17. progressive fibrotic processes begins
around the capillaries
This fibrotic scar tissue will eventually
cause obliteration of blood vessels---
depriving the cells of nutrition ,oxygen
and elimination of waste
Eventually leading to loss of cell function
,decreased resistance to infection and death
of all cell types…with the net result of
PROGESSIVE FIBROATROPHY
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20. • Oral mucous membrane
* Short term effects –related to the radiosensitive
vegetative intermitotic cells of the basal layer of the
mucous membrane.
* Initially —redness and inflammation—mucositis
*as therapy continues – formation of whitish yellow
pseudomembrane—desquamated epithelial layer
*2 months after therapy—rapid healing---
• mucosa becomes atrophic,thin relatively
avascular.
www.indiandentalacademy.com
21. Taste budsTaste buds
*are radiosensitive—extensive degeneration
*loss of taste acuity during second or third
week of radiotherapy
*recovery usually takes between 60-120 days
www.indiandentalacademy.com
22. Salivary glandsSalivary glands
The parenchymal component of salivary glands is
radiosensitive
Short-term effects –inflammatory response
Long-term effect progressive fibrosis,adiposis,loss
of fine vasculature with parenchymal
degeneration---accounting for xerostomia.
Marked reduction of salivary flow is seen in the
1st
two weeks
Xerostomia ,decreased ph of saliva (6.5to 5.5)---
this is low enough to cause decalcification
Buffering capacity falls by 44%www.indiandentalacademy.com
23. Flora thus becomes more acidogenic in
saliva and plaque ---this along with thick
viscous ,acidic saliva---renders patient
susceptible to radiation caries. Oral micro
flora changes –strept.mutants,lactobacillus
and candidasis
Recovery—6 to 12 months
If not –unlikely that there will be significant
recovery
www.indiandentalacademy.com
25. Radiation cariesRadiation caries
Rampant form of decay
Irradiation of the teeth does not influence the
decay but the changes induced in the salivary
glands and saliva are responsible for this decay
There are three types of radiation caries
-----superficial lesions—B,O,Li,P surfaces
-----primarily involving cementum and dentin
in the cervical region
-----dark pigmentation of the entire crown
www.indiandentalacademy.com
26. Reducing ----daily application for 5 minutes
of a viscous topical 1% neutral NaF gel
--------avoidance of dietary sucrose
www.indiandentalacademy.com
28. TeethTeeth
Severity of damage is dose dependent
If irradiation precedes calcification –tooth bud
destroyed
After calcification has begun—inhibition of
cellular differentiation –malformations and
arresting growth
Adult teeth are relatively radioresistant
Pulpal tissue –reverting and fixed postmitotic cells
—may show long –term fibroatrophy
No discrenible effect on the crystalline structure of
enamel ,dentin or cementumwww.indiandentalacademy.com
29. BoneBone
Primary damage—results from damage to
the vasculature of the periosteum and
cortical bone
Also the radiation tends to destroy
osteoblasts and to a lesser extent osteoclasts
Bone marrow fatty bone marrow and
fibrous connective tissue
marrow hypo vascular,hypoxic and
hypo cellular
Degree of mineralization reduced brittle
www.indiandentalacademy.com
31. OsteoradionecrosisOsteoradionecrosis
Decreased vascularity -renders bone
susceptible to infections
Source of these infections may be from
radiation –induced breakdown of the oral
mucous membrane ,mechanical damage
tooth extraction ,denture sore,PD lesion
or radiation caries...
Mandible > maxilla
www.indiandentalacademy.com
33. Relevance of Radiation inRelevance of Radiation in
OrthodontiaOrthodontia
• Most commonly taken radiographs in
Orhtodontia are :-lateral cephalogram
panoramic radiograph
• hand- wrist x-rays
• Exposure of critical organs which are:-
active bone marrow
thyroid gland
salivary glands
optic lenswww.indiandentalacademy.com
34. Exposure is of low doses …example for the
formation of cataract 2Sv(200 rem)but in opg
dose exposed to in the form of scattered radiation
is only 80 microSv
Also studies by Danforth and Gibbs
Thyroid160-370 microGys
Pitutary 70-490 microGys
Salivary glands 393 microGys
As these doses are well below the maximum
permissible dose the harmful effects still remain
uncertain
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35. Harmful effects manifest as increased
probability of a normally occurring disease
Bear in mind ALARA principle
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36. Maximum Permissible DoseMaximum Permissible Dose
Two categories :-ouupationally exposed
Non occupationally exposed
Whole body Isolated areas of
body
Occ.exp. 0.05Svyear 0.75Svyear
Non occ. 0.005Svyear 0.075Svyear
Exp.
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38. Patient protection
1) Intensifying screens
2) Focal spot to film distance
3) Collimation
4) Filtration
5) Lead aprons and collars
6) Good radiographic techniques
www.indiandentalacademy.com
39. Protection of PersonnelProtection of Personnel
Barrier/position and distance rule
Operator never hold film
Personnel should wear film badges
Regular checks of x-ray equipment for
spills
www.indiandentalacademy.com
40. IS A COLLECTION OF SIGNS AND
SYMPTOMS EXPERIENCED BY PERSONS
AFTER ACUTE WHOLE BODY EXPOSURE
TO RADIATION
1)Prodromal Period
2)Hematopoietic Syndrome
3)Gastrointestinal Syndrome
4)Cardiovascular Syndrome
Acute Radiation SyndromeAcute Radiation Syndrome
www.indiandentalacademy.com
41. PRODROMAL PERIODPRODROMAL PERIOD
WITHIN FIRST MINUTES TO HOURSAFTER
EXPOSURE ,SYMPTOMS OF
GASTROINTESTINAL TRACT
DISTURBANCES MAY OCCUR.
ANOREXIA,NAUSEA
VOMITTING,DIARRHEA,WEAKNESSAND
FATIGUE
SEVERITY AND TIME OF ONSET R DOSE
RELATED
www.indiandentalacademy.com
43. HEMATOPOIETIC SYNDROMEHEMATOPOIETIC SYNDROME
2 TO 7 Gy CAUSES INJURY TO THE
HEMATOPOETIC STEM CELLS OF THE
BONE MARROW AND SPLEEN.
FALL IN THE NUMBER OF
CIRCULATING
GRANULOCYTES’PLATELETS,AND
ERTHROCYTES.
www.indiandentalacademy.com
44. THE CLINICAL SIGNS OFTHE CLINICAL SIGNS OF
THE HEMATOPOIETICTHE HEMATOPOIETIC
SYNDROME INCLUDE-SYNDROME INCLUDE-
1)INFECTION-LYMPHOPENIAAND
GRANULOCYTOPENIA
2)HEMORRHAGE—
THROMBOCYTOPENIA.
3)ANEMIA—ERYTHOCYTE
DEPLETION
IF PATIENT DOES NOT RECOVER DEATH
MAY OCCUR IN 10 TO 30 DAYS.
www.indiandentalacademy.com
45. GASTROINTESTINALGASTROINTESTINAL
SYNDROMESYNDROME
7 to 15 Gy causes extensive damage to the rapidly
proliferating epithelial cells of the intestinal villi
with resultant –denudation of mucosal surface
,loss of plasma and electrolytes
these changes are responsible for
diarrhea,dehydration,and weight losses well
as invasion of endogenous intestinal bacteria
producing septicemia.
www.indiandentalacademy.com
46. These damages along with the hematopoietic
damage together contribute to the signs and
symptoms of GASTROINTESTINAL
SYNDROME
www.indiandentalacademy.com
47. CARDIOVASCULAR AND CENTRALCARDIOVASCULAR AND CENTRAL
NERVOUS SYSTEM SYNDROMENERVOUS SYSTEM SYNDROME
Exposure to a dose in the range of 50Gy will
cause death in a few minutes to 2 days
There is collapse of the cardiovascular
system and autopsies reveal necrosis of the
cardiac muscle .
Damage to the nervous system manifests as
patient showing intermittent stupor ,inco-
ordination,disorientation and convulsions
www.indiandentalacademy.com
49. ContentsContents
Introduction
Mechanisms of Cross Infection
Important Pathogens in Infection Control
Control of Cross-Infection
Sterilization in Orthodontics
www.indiandentalacademy.com
50. Pathways for Cross-Contamination
Patient to dental team
Dental team to patient
Patient to patient
Dental office to
community
Modes of disease spread :-Direct contact
Indirect contcat
Droplet infection
IntroductionIntroduction
www.indiandentalacademy.com
51. Mechanism or site of entry into
body:-
through breaks in
skinmucous membrane
through inhalation
www.indiandentalacademy.com
53. There are several important disease in
infection control but the ones of most
significance in the dental office are:-
Hepatitis B virus
HIV
Herpes Simplex Virus
www.indiandentalacademy.com
54. Infectious agent Disease or condition Route of
transmission
Incubation period Communicable
period
Hepatitis A virus ‘Infectious hepatitis’
Type A Hepatitis
Feco-oral, Food ,
water, shellfish
2 to 6 wks (av. 28
to 30 days)
2 to 3 wks before
onset (jaundice)
through 8 days
after
Hepatitis B Virus ‘Serum hepatitis’ Type
B Hepatitis
Blood, saliva, body
fluids,sexual
contact, perinatal
2 to 6 months ( av.
60 to 90 days )
Before, during &
after clinical signs
Carrier state:
indefinite
Delta Hepatitis
Virus ( HDV )
Delta Hepatitis Coinfection with
HBV, Blood,
Sexual contacts,
Perinatal
2 to 10 weeks All phases
Non-A, Non-B
Hepatitis Virus
Non-A, non-B hepatitis Similar to HBV 2 to 6 months Like HBV
Epidemic non-A non-B Feco-oral
Contaminated
water
15 to 64 days Not known. Maybe
like HAV
Human
Immunodeficienc
y Virus ( HIV )
Acqired
Immunodeficiency
Syndrome ( AIDS )
Blood & blood
products
( infected i.v
needles ), sexual
contact, perinatal,
3 months to 5
years
2 years for
transfusion case )
From
asymptomatic
through onset of
opportunistic
infections
www.indiandentalacademy.com
55. Herpes Simplex
Virus
Type I ( HSV -1 )
Type II (HSV-2 )
Acute Herpetic
gingivostomatitis
Herpetic labialis
Ocular herpetic
infections
Herpetic Whitlow
Saliva, direct
contact ( lip, hand )
Indirect contact
(on objects, limited
survival)
Sexual contact
2 to 12 days Labialis: one day
before onset until
lesions are crusted
Acute stomatitis:
7wks after
recovery
Asymptomatic
infection: with viral
shedding
Reactivation
period: with viral
sheddingVaricella-zoster
virus (VZV)
Chickenpox
Shingles
Direct contact
Indirect contact
Airborne droplet
2 to 3 weeks 5 days prior to
onset of rash until
crusting of vesicles
Epstein- Barr Virus
( EBV )
Infectious
mononucleosis
Direct contact
Saliva
4 to 6 weeks Prolonged
Pharyngeal
excretion 1yr after
infection
Cytomegalovirus
( CMV )
Neonatal CMV
infection
CMV disease
Perinatal
Direct
contact(most body
secretions)
Blood transfusion
Inexact
3 to 8wks after
transfusion
Months to years
www.indiandentalacademy.com
56. Treponema
pallidum
Syphilis Direct contact
Transplacental
10 days to 10 weeks Variable and
indefinite
Maybe 2 to 4 years
Neisseria
gonorrhoea
Gonorrhea Direct contact
Indirect contact
(short survival of
organism)
2 to 9 days During incubation
Continued for
monthsand years if
untreated
Group A
streptococci
(Beta-hemolytic)
Streptococcus
pyogenes
Streptococcal sore
throat
Scarlet fever
Impetigo
Erysipelas
Respiratory
droplets
Direct contact
1 to 3 days 10to 21 days,
untreated
Many nasal
oropharyngeal
carriers
Staphylococcus
aureus
Staphylococcus
epidermidis
Abscesses
Boils (furuncles)
Impetigo
Bacterial
pneumonia
Saliva
Exudates
Nasal discharge
4 to 10 days
Variable and
indefinite
While lesions drain
and carrier state
persists
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57. Influenza
viruses
Influenza Nasal discharge
Respiratory
droplets
24 to 72 hrs 3 days from
clinical onset
Measles Virus
(Morbilivirus)
Rubeola (measles) Direct contact
Saliva
Airborne droplets
8 to 13 days to
fever, 14 days to
rash
Few days before
fever to 4 days
after rash appears
Rubella virus
(Togavirus)
Rubella (German
measles)
Nasopharyngeal
secretions
Dirrect contact
Airborne droplets
16 to 23 days From 1wk to at
least 4 days after
rash appears
Congenital Rubella
Syndrome
Maternal infection,
first trimester
Infants shed virus
for months after
birth
Mumps virus
(Paramyxovirus
)
Infectious parotitis Direct contact
(saliva)
Airborne droplets
2 to 3 wks
(average 18 days)
From 1 to 7 days
before sympoms
until 9 days after
swelling
Polio virus
types 1,2,3
Poliomyelitis Direct contact
(saliva), Droplet,
Feco-oral
7 to 14 days Probably most
infectious 7 to 10
days before and
after onset of
symptoms
Mycobacteriu
m Tuberculosis
Tuberculosis Droplet nuclei
Sputum
Upto 6 months Long, repeated
exposure usually
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59. An infection-control program comprises two distinct
areas: exposure control and hazard
communication.
Exposure control covers sterilization and disinfection,
waste management, and employee including personal
protective equipment and bodily-fluid-exposure
protocols.
Hazard communication requirements include a periodic
checklist for OSHA compliance, drills for hazard
communication plans (chemical spills, emergency first
aid, and fire or tornado evacuation), secondary labeling of
hazardous chemicals, Material Safety Data Sheets, x-ray
updates, and properly displayed state and federal posters.www.indiandentalacademy.com
60. TerminologiesTerminologies
Sterilization it is the process of destroying all
forms of microbial life
Disinfection it is defined as the removal of or
inactivation of microbes.thus it implies only some
and not all pathogenic organisms can be
eliminated by this method.
Anti-septicsthese are substances that prevent
the growth or action of microbes by either
destroying them or inhibiting their actions
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61. Sanitizersreduce the microbial population to
safe levels as judged by public health
requirements.they are usually chemical agents that
kill close to 99.9%of the organisms.
Germicideskill the growing forms but not
necessarily the resistant spores.
Bacterio static agents agents which have the
ability to inhibit he growth of bacteria.
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62. SterilizationSterilization
Is a process intended to kill all
microorganisms whether vegetative or
pathogenic .
It is the highest level of microbial killing
that can be achieved
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63. The protocol for sterilization of instruments
is usually
1)holdingpresoaking
2)pre cleaning
3)sterilization process
4)aseptic storage and handling of
instruments
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64. Holding PresoakingHolding Presoaking
If instrument not to be cleaned immediately
soak in holding solution prevents
salivablood from drying up.
Holding solution usually is a germicidal
Discard solution at least once a day
Avoid prolonged soakingcorrosion
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65. Pre cleaningPre cleaning
Reduces amount of microbes present ,but
more importantly removes blood saliva and
other materials that may insulate microbes
from the sterilizing agent.
May be achieved by
ultrasonic
manual
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66. Sterilization ProcessSterilization Process
A) Physical agents
B) Sunlight
C) Dry heat:-
flaming
incineration
hot air
D) Moist heat :
boiling
steam under pressure
E) Filtration:-
membranes
asbestos padswww.indiandentalacademy.com
68. In dentistry the procedures used are:-
1)Heat sterilization
2)Gaseous sterilization
3) Liquid chemicals sterilization
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69. Heat sterilizationHeat sterilization
a) Moist heat:-steam pressure autoclave
b) Unsaturated chemical vapour:- chemiclave
c) Dry heat:- conventional dry heat ovens
:- short cycle high temperature dry
heat ovens
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70. Steam Pressure AutoclaveSteam Pressure Autoclave
Sterilizes by bringing about oxidation as well as
denaturing proteins
It is the latent heat and not the pressure built
inside by steam within the closed chamber that is
responsible for killing of the microbes
Two cyclesStandard..20 –30 mins.at 250°f
Flash cycles..3-10 mins.at 273°f
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72. Unsaturated Chemical vaporUnsaturated Chemical vapor
Chemical solution heated in a closed
solution-chemical vapor kills the
microbes
0.23%formaldehyde,72.38%ethanol along
with acetone,ketone and water
20 min at 270°f
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73. Advantages
1)eliminates or reduces the corrosion of
susceptible instruments.
2)dry instruments available at end of cycle
Disadvantages
1)items sensitive to elevated temp.will get
damaged
2)pre drying of inst.a must
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75. Dry HeatDry Heat
Conventional dry heat ovens
*heat chambers wherein heated air is circulated by
gravity convection
*320f for 30 min
*place packs at least 1 cm apart to allow for the hot
air to circulate between wrapped instruments
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77. Short –cycle high temperature dry heat
ovens
Are force draft ovens
370°f to 375°f for 6 to 12 mins
Advantages :-1)instruments sensitive to
corrosion may be safely sterilized
2)effective rapid cycles are possible
3)items dry at end of cycle
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78. Disadvantage
Instruments sensitive to elevated temp. will get
damaged
Ethylene oxide sterilization
for complex, delicate , heat sensitive inst.
aeration of about 24hours must pror to use
of instruments especially porous and plastic
ones
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80. Boiling waterBoiling water
Even though seen to be used commonly it
does not kill spores and does not bring
about sterilization of instruments
Heat reaches and kills the blood borne
pathogens
100° for 10 min.
Thus more than sterilization it is a process
of high level disinfections
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83. Chemical MethodsChemical Methods
Chemical agents are used for controlling of
microbes on body surfaces and on
inanimate objects are grouped under
disinfectants
These includeantiseptics
sanitizing
degerming
disinfecting agents
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84. Qualities of a universalQualities of a universal
disinfectantdisinfectant
1)destroy all forms of microorganisms
within a practical period of time
2)non-toxic,non-allergic,non-irritating
3)non-corrosive,non-discolouring ,non-
degrading
4)good wettability and penetrabilityfor
effective contact even in the presence of
blood and exudate
5)readily soluble in available solvents
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85. ClassificationClassification
Spaulding in 1972
A. High level disinfectants
Eg:-ethylene oxide gas,immersion
glutheraldehyde solutions
B. Intermediate level disinfectants
Eg:-formaldehyde ,chlorine
compounds,alochol,iodophors ad phenolic
compounds
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87. Categories of chemicalCategories of chemical
disinf.disinf.
A) Alcohols
B) Aldehydes
C) Halogens
D) Surfactants
E) Quanternary ammonium compounds
F) Phenols and Phenolic compoundwww.indiandentalacademy.com
88. A. Alcohols
bactericidal and fungicidal but not
sporicidal
MOA :- denature proteins
solvent action on lipids
Ethyl and isopropyl alcohols…most
commonly used
optimum conc. 70% range 60-95%
If conc.falls below 45%antmicrobial
activity is slow and uncertain
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89. Alkalating agents
Formaldehyde
Gaseous state …used as a fumigant
MOA :- protoplasmic poison
denaturing proteins
Disadvantage:-pungent odour
,irritating t skin ,poor penetrating and
slow acting
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90. Gluteraldehyde :-
less pungent volatile and irritating with
better disinfectant properties
broad spectrum of
activity2%sol.bactericidal,tubercu
locidal and virucidal in 10 mins and
sporicidal in 10 hours
gluteraldehyde+iodine comp.+bleach
recommended for use against Hb virus
where sterilization not feasible
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91. They also have a low surface tension
and can thus penetrate blood and
exudate thus reaching instruments
surfaces
Also used for disinfection of
impressions
Cidex , sporicidin, glutorex
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94. Chlorine
Sanitizing agent
Elemental chlorine used for water
purification
may also be used as a surface
disinfectant
conc. 2.5%
gloves must be worn
corrosive to metals
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95. Iodine :- used for wound and skin
antisepsis
Tinctures of iodine are usually used in
1,5and 7% conc. Which destroy 90%of
bacteria in 90,60 and 15 sec.
respectively
• Iodophors:- composed of complexes
of iodine and surface active organic
carrier molecules from which iodine
gradually released .
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97. Phenols :-
As disinfectants and antiseptics
MOA:-denaturing of proteins or damage to cell
membrane
Bacteroicidal and bacteriostatic…but poor
viricidal properties
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99. These include :-
Gloves
Mouth masks
Protective eyewear
Hand washing
Immunization
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100. GlovesGloves
The need for gloving
The practices of gloving not only
provides protection to dentist but also to
the patient
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102. Patient Care GlovesPatient Care Gloves
Disposable gloves
Do not wash gloves with detergents in an attempt
to reuse
While leaving chairside remove gloves
While working chair side try and put to use the
practice of double gloving
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104. Protective EyewearProtective Eyewear
Protection from microbes
Eg:HSV, Hepatitis B
Protection against physical damage
Protection from impact damage
Protection from splashes of chemicals
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105. Preferable to use goggles over glasses as
former not only provides protection from
front splash and impacts but also from side
impacts and splashes
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106. Hand washingHand washing
Two types of micro flora
resident flora
transient flora
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107. Resident flora:colonize and become
resident
can never be completely
eliminated
less imp. In causing
disease
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108. Transient flora:acquired whilst dealing
with contaminated objectssurfaces
do not colonize or
survive for long periods on the hand
usually pathogenic
can be removed by
following a good hand washing protocol
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109. Hand washing products containing low
levels of microbial agents used in a 10 –30
sec.hand wash routine minimizes the no.of
transient flora and aids in reducing the no.of
resident flora too.
Chlorhexidine digluconate ,povidine
iodine,parachlorometaxylonol
Washing of hands before and after gloving
very imp.
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111. MasksMasks
Protect mucous membrane of mouth and
nose from contact with
aerosolssprayssplashes of oral fluids from
patients…also in turn protect patient
Composed of material that filters out 95%-
99.9%of 2-3 micrometer size particles that
directly contact it
They should be form-fitting over the bridge
of the nose to reduce fogging of eyewear
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112. Dispose mask once it gets moist
resistance to airflow through the mask
increasesmore unfiltered air is allowed to
pass by the edge of the mask
Use disposable maskschanging between
patients
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113. ImmunizationImmunization
Hepatitis
The HBV is an infectious agent associated
with acute and chronic hepatitis .
Major cause of necrotizing vasclitis,cirrhosis ,
and primary hepatocellular carcinoma.
Found primarily in blood and blood products
…may also be present in other body
fluids…saliva , semen,tears,urine
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114. Transmitted parenterally,sexual
contact,mother to fetus
HBV relatively environmentally stable…
potential for indirect transmission via
contact with contaminated inst.
Best protection is by immunization
Two vaccines Recombivax HB and
EngerixB
Regime :-1.0ml doses given at 0, 1, and 6
mths
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115. Following vaccination protective levels of
antibodies are believed to persist for seven
years
Need for booster dose is being debated
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116. Sterilization of OrthodonticSterilization of Orthodontic
PliersPliers
autoclave or chemiclave .
The only major obstacle of pliers
sterilization is related to their corrosion
suceptibility.
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117. corrosion resistance of orthodontic grade
steel is directly proportional to its chromium
content and inversely proportional to its carbon
content .
disruption of chromium oxide layer renders them
suceptible to corrosion.
Instruments made of carbon or 400 series steel are
more susceptible than those made of 300 series
steel.
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118. Steps to prevent corrosionSteps to prevent corrosion
first be cleaned thoroughly and rinsed with
distilled water .
do not allow contaminants to dry
Tap water to be avoided– use only distilled water
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119. Chrome-plated instruments should be autoclaved
separately from stainless steel ones.
Detergents with chloride bases should not be used
, Purple or black staining is caused by exposure to
ammonia.
*
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120. ArchwiresArchwires
Contaminated archwires are sterilized in
divided plastic containers
Cut to appropriate length and kept
overnight in gluteraldehyde solution
Thereafter stored in binsuntil ready to be
used
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121. Recycling of archwires
the relative high costs of archwires has lead to one
trying out the practice pf reclcycling of arch wires
Both cold and heat sterilization have been tried
Heating cycle should not exceed 235 C for a total
of 20 minsto keep impact on wires properties to
the minimum.
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122. Studies on Recycling ofStudies on Recycling of
Orthodontic Arch wiresOrthodontic Arch wires
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123. Mayshew ,Kusy Am.j.OrthoMayshew ,Kusy Am.j.Ortho
19881988
Effect of sterilization on mechanical properties
and surface topography of 0.017” x 0.025”
NiTinol and Titanal wires
Three methods:-
dry heat at 180 c for 60 min
formaldehyde alcohol vapour ,132c for 30 min
steam autoclave ,121 c for 20 min at 15-20 psi
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124. Tests conducted:-
Three point bending—elastic moduli
Surface topography –laser scattering
Tensile properties—instron utm
Results:-
No significant change in tensile properties with
any sterilization procedure
No change in elastic moduli
No apparent effect on surface topography
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125. Buckthal, Kusy :Am.J.Ortho .Buckthal, Kusy :Am.J.Ortho .
19981998
Effects of cold disinfectabnts on mechanical
properties and surface topography of 0.017” x
0.025” NiTinol and Titanal wires
Three disinfectants tested:-
2%acidic phetaraldehyde for 10 hours
Cholorine dioxide for 6 hours
Iodophor for 10 hours ..mixture at the ratio of
1/256 with water.
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126. Tests :-
Bending ,tensile,laser spectroscopy
Results :-
No change in elastic moduli
No change in surface topography
No change in tensile properties
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127. Laboratory AsepsisLaboratory Asepsis
Counter tops:-wipe counter tops with effective
disinfectants.
Impressions:-
easily contaminated with blood and saliva
microorganisms easily transferred from
contaminated impressions to casts where they can
remain viable for upto 7 days…thus providing a
path for cross contamination from the clinic to the
laboratory personnel
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128. Impressions after being removed from the mouth should
be rinsed under running water …this enables the removal
of adhering microorganisms
They are then placed into plastic bags with appropriate
disinfectants for approximately 15 mins…followed by
their removal and rinsing of the disinfectant…they are
now ready to be poured
If the impression is sensitive to immersion an alternate
would be to spray the impression with the appropriate
disinfectant and wrap it with a paper towel moistened with
the same disinfectant for 15 mins.
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129. BibliographyBibliography
White and Pharoah: Oral
Radiology:Principles and Interpretations
Robert langleins,Olaf
e.langland,McDavid:Panoramic Radiogaph
Casebow, M.P.:patient doses from
Orthopantomograph x-ray exposures,Br. J.
Radiol.,46:230,1973
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130. Chris H. Miller and Charles J.
Palenik:Infection Control and
management of Hazardous
Materials for the Dental Team
Mayshew,Kusy:Recycling of
orthodontic wires:Am. J. Ortho
1988
Buckthal,Kusy: Am. J. Ortho.1998
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