Willhelm Conrad Roentgen
who discovered X-rays?
C. Edmund Kells
who was the first person to make practical use of X-rays in dentistry?
process in which electrons are removed from orbital shells of electrically stable atoms through collisions with X-ray photons
what is ionization?
tubehead, extension arm, control panel
what are the primary components of a dental X-ray machine?
name the negative electrodes inside the X-ray tube?
name the positive electrode inside the X-ray tube?
master switch, indicator light, selector buttons, exposure button
what does the control panel control?
primary, secondary, scatter
name the three types of radiation?
describe the difference between radiopaque and radiolucent
air space, soft tissue
give examples of structures that appear radiolucent on a radiograph
tooth enamel, metal restorations
give examples of structures that appear radiopaque on a radiograph
quality, quantity, intensity
what are 3 characteristics of the X-ray beam?
which exposure factor controls contrast?
dark areas, white areas, gray areas the dentist sees
what is meant by density on a dental radiograph?
what is the name of the process that results in the harmful effects of X-rays?
what is the name of the time period between X-ray exposure and the appearance of symptoms?
passed through generations
what is meany by genetic effects of radiation?
traditional, systeme internationale
name the two systems of radiation measurement
what is the maximum permissible dose of radiation for occupationally exposed persons?
restrict size and shape of X-ray beam
what is the purpose of the collimator?
remove low energy long wavelength least penetrating xray
what is the purpose of the aluminum filter?
from neck down to lap
what precautions should be taken when one is handling the lead apron?
fast speed film
what is the most effective measure in reducing a patients exposure to radiation?
in digital radiography, what replaces intraoral film?
direct and indirect imaging
what are the two fundamental techniques for intraoral digital radiography?
phosphor storage plates
which of the digital techniques requires scanning of image receptors?
keeps patients fingers from being exposed and assists operator in properly placing film sensor in PID
how does the use of film holders protect the patient from unnecessary radiation?
size and shape
what is the primary difference between a film holder and a digital sensor holder?
assist in position of PID in relation to tooth and film or sensor
what is the purpose of a beam alignment device?
film base, thin adhesive layer, gelatin, silver halide crystals, protective layer
what are the 5 components of intraoral films?
image after exposure before its processed
what is latent image?
white side (tube head) of film faces toward teeth
how can you tell which side of the film is placed toward the tube?
what number film is used for adult radiographs?
what size film is used for occlusal radiographs?
panoramic and cephalometric; rigid anf flexible styles
what are two types of extra oral film cassettes?
increases radiation and decreases amount of exposure
what is an intensifying screen?
extraoral: taken outside mouth
intraoral: taken inside mouth
intraoral: taken inside mouth
how does the extraoral film react differently from intraoral film?
referring patients to specialists, insurance claims or legal purposes, sending copies of records to new dentists if you’re moving
when might it be necessary to duplicate X-rays?
should be stored according to manufacturers rules. involves protection from light, heat, moisture, chemicals, and scatter radiation
what precautions should be taken when storing X-ray film?
box is marked
how can you find expiration date of a package?
developing, rinsing, fixing, washing, drying
what are the 5 steps in processing dental radiation?
which is the most widely used form of processing solution?
daily and changed every 3-4 weeks
how often should processing solutions be replenished?
low intensity light in red-orange spectrum
what is a safelight?
what is the minimum distance between the safelight and the working area?
68 degrees F
what is the optimum temperature for the water in the manual processing tanks?
less processing time, time and temperature auto, less equipment used, less space required
what is the major advantage of automatic film processing?
beginning of each day
how often should the levels of solution in the automatic processor be checked?
no. chemicals in manuel processing should never be used in the automatic processor
are manual processing solutions and automatic processing solutions interchangeable?
consumer-patient radiation health and safety act
what federal act requires persons who take radiographs to be trained and certified?
what type of consent is necessary before a patient is exposed for dental images?
under state laws, who is allowed to prescribe dental images?
who is the legal owner of a patients dental images?
regular testing to detect malfunctions, techniques, maintenance
what is meant by quality reassurance?
specific tests used to monitor X-ray equipment, supplies, and film
what are quality control tests?
every time you open one
when should you check a box of film for freshness?
should you use a film cassette that has scratches?
what is one of the most critical areas in a quality control program?
to check safelight
what is the purpose of the coin test?
how often should processing solutions be replenished?
why are the reference radiograph and the stepwedge used?
film takes longer to clear
how can you tell when the fixer loses its strength?
deals with management
what is the purpose of a quality administration program?
DA’s, every staff member
which staff members have to be aware of the quality administration program?
what unique infection control problems occur in dental imaging?
surfaces not easily cleaned
what surfaces must be covered with barriers?
what precautions should be taken when one is handling contaminated film or PSP’s?
until patient is seated and can view opening of the package
when should the packages that contain positioning insurgents be opened?
gloves, masks, and eyewear
what personal protective equipment should the operator wear while exposing radiographs?
chemical resistant utility gloves
what type of gloves should be worn while one is disinfecting the radiography operatory?
what precautions must be taken when films are transported to the darkroom?
box shows upper and lower teeth in occlusions. PA shows entire tooth from occlusal surface to 2-3 mm beyond apex
what is the difference between a bitewing and a periapical image?
bisecting technique and paralleling technique
what are the two techniques that can be used for exposing images?
to avoid exposing the same area twice
why is an exposure sequence important?
anterior (canines and incisors)
when exposing images, in which area of the mouth should you begin with?
which projection should be the first for posterior exposures?
exposes hands and fingers to unnecessary radiation
why is it not recommended to have the patient hold the film or sensor during exposure?
BAI- bisecting angle
what type of film or sensor holders can be used int he bisecting technique?
overlapped contact areas
what error occurs when the horizontal angulation is incorrect?
elongated and foreshortened
what two errors occur when the vertical angulation is incorrect?
close to the crown extends at an angle into the floor of mouth
in the bisecting technique, how is the film or sensor placed in relation to the teeth?
to detect inter proximal decay
what is the purpose of bitewing images?
what horizontal angulation should be used for bitewing images?
what size film is used for adults in the occlusal technique?
examine large areas of the upper or lower jaw
when are occlusal radiographs indicated?
vision hearing mobility, developmental
what physical disabilities may affect dental patients?
under what circumstances would you hold a film sensor for a patient?
placing cotton roll on bite block where crowns are missing
for partially edentulous patients, how can you modify the technique for using a bite-block?
when exposing images on a pediatric patient, how can you best describe the tube head for a patient?
milliamperage, kilovoltage exposure time must be reduced for smaller size
what changes must be made in exposure factors when one is exposing dental images on a pediatric patient?
what size film is recommended for a pediatric patient with all primary dentition?
anterior films easier preform premolar films before molars
why is the exposure sequence especially important when one is taking X-rays on a patient with severe gag reflex?
properly placed, exposed or processed
what is the definition of a diagnostic quality image?
film speed in mount with dots facing up
when mounting radiographs, what is the ADA’s?
to know how to mount pictures
why is it important for the dental assistant to recognize anatomic landmarks?
decrease amount of radiation
why is it important to avoid retakes?
when large areas of the skull or jaw must be examined
when are extraoral radiographs needed?
bwx and pa’s because panx doesn’t give you full detail
what types of film might be needed to supplement a panoramic image? why?
aka image layer, 3d horse-shoe shaped zone. area of ideal focus
what is a focal trough?
provide 3d info rather than 2d
why is a cbct image better than a pa image?
allow slow radiation
why are cbct image better than panx image?
useful for evaluating large areas viewing entire dentition in a single image
what is the purpose of extraoral radiographs?
what is the name of the device that may be added to a panoramic unit to allow the operator to easily position the film and patient
reduces amount of scatter radiation
what is the purpose of a grid?
athorogrpahy and cbct
what type of imaging is best for soft tissues of the TMJ?