Chapter 1 Importance Of Radiographs Flashcards
RADIATION HISTORY
• Radiology is a method of recording images of dental structures by the use of x-rays
• X-rays were first discovered by Dr. Wilhelm Conrad
Roentgen on November 8, 1895 in Wurzberg, Bavaria
• In his honour, x-rays are often referred to as Roentgen Rays
W.C Roentgen
Discovered x-rays
Dr. Otto Walkoff
First dental radiograph
Dr. Edmund Kells
First dental radiograph in United States
Living patient 1896
First pre wrapped intra oral radiographs
• By 1913, the Eastman Kodak Company manufactured the first pre-wrapped intraoral radiographic films
Who introduced Bisecting technique
• Weston Price, a Cleveland dentist, introduced the bisecting technique in 1904
• Howard Riley Raper redefined the original bisecting technique and introduced the bitewing technique in 1925 also wrote first text in 1913
Who applied parallel technique in dental
Franklin W. McCormack in 1920 applied the paralleling technique in dental
F.Gordon Fitzgerald
•F. Gordon Fitzgerald, the “father of modern dental radiography” reviewed interest in the paralleling technique with the introduction of the long-cone paralleling technique in
1947
RADIATION
RADIATION
• A form of energy carried by waves or stream of particles
XRadiation
X-RADIATION
• A high-energy radiation produced by the collision of a beam of electrons with a metal target in an x-ray tube
X-ray
X-RAY
• A beam of energy that has the power to penetrate substances and record image shadows on photographic film
X-RAY
• Weightless bundle of energy (x-ray photon)
• Possess particles of waves and particles
• Invisible and cannot be detected by any of the senses
• Possess no mass, no weight, no charge
• Travel at the speed of light
• Possess short wavelengths and high frequency
X-RAY
• Travel in straight lines and can be deflected or scattered
• Absorbed by matter
• Interact with materials they penetrate and cause ionization
• Produce an image on photographic film
• Cause biological transformations in living cells
Radiology
RADIOLOGY
• The study or science of radiation that deals with the use of x-rays, radioactive substances, and other forms of radiant energy in the diagnosis and treatment of disease
Radiograph
RADIOGRAPH (RADIOGRAM)
A picture that is, a visible photographic record on a film produced by the passage of x-rays through an object or body
Dental Radiography
DENTAL RADIOGRAPHY
• The making of radiographs of the teeth and adjacent structures by the exposure of film to x-rays
Dental radiographer
DENTAL RADIOGRAPHER
• Any person who positions, exposes, and processes dental x-ray film
Matter
MATTER
• Anything that occupies space and has mass
• When matter is altered, energy results
• All matter is composed of atoms
Atom
ATOM
• A tiny, invisible particle that is the fundamental unit of matter
• The smallest part of an element that has the properties of that element
ATOMIC STRUCTURE
ATOM
• An atom consists of 2 parts: a central nucleus and orbital electrons
• At present, 118 different atoms have been identified
• Hydrogen - simplest atom (atomic number = 1)
• Atoms are arranged in increasing atomic number on a chart known at the “PERIODIC TABLE OFTHE ELEMENTS”
Nucleus
NUCLEUS
• The core of the atom
• Composed of protons (positively charged particles) and neutrons (neutrally charged particles ie: no electrical charge)
• The nucleus of an atom occupies very little space
• Most of the atom is empty space
• Ex: atom = football stadium nucleus = football
Electrons
ELECTRONS
• Tiny negatively charged particles that have very little mass
• The arrangement of electrons and neutrons in an atom resembles that of a miniature solar system
• Electrons travel around the nucleus in orbtis or shells like the planets revolve around the sun
ORBITS / SHELLS
• An atom contains a maximum of 7 shells
• The shells or orbits are designated with the letters K L M NO P Q
• The K shell is located closest to the nucleus and has the highest energy level
• Each shell has a maximum number of electrons it can hold
Strongest Binding energy
BINDING ENERGY / BINDING FORCE
• Electrostatic force or attraction between the positive nucleus and the negative electrons
• Determined by the distance between the nucleus and the orbiting
electron
• It is different for each shell
• The strongest binding energy is found closest to the nucleus in the
K-shell
Molecules
• Molecules are atoms that bond together in different ways; atoms are joined by chemical bonds
• Molecules can be formed by the transfer of electrons, or by the sharing of electrons
b
• Like the atom, a molecule is a tiny invisible particle
• Sometimes there are 2 or more atoms; other times there may be thousands
• When 1 atom of oxygen bonds with 2 atoms of hydrogen, it forms a water molecule Eg: H20 (simplest molecule)
Ionization
IONIZATION
• Production of ions, or the process of converting an atom into
ions
• Deals only with electrons and requires sufficient energy to overcome the electrostatic force that binds the electron to the nucleus