Key Terms* Flashcards
non-critical instrument
instruments that do not come in contact with mucous membranes
quality administration
the management of the quality assurance plan in the dental office
hypercementosis
the excess deposition of cementum on the root surfaces of teeth (appears radiopaque)
control panel
a part of the x-ray machine that contains an on/off switch, an indicator light, and exposure button and control devices to regulate the x-ray beam
external oblique ridge
a linear prominence of bone located of the external surface of the body of the mandible (appears radiopaque)
tomogram
an extraoral radiograph used to examine the bony components of the temporomandibular joint
particulate radiation
tiny particles of matter that possess mass and travel in straight lines at high speeds (electrons, protons, neutrons)
bitewing technique
an intraoral radiographic technique in which the interproximal surfaces of teeth are examined
control devices
the components of the control panel of the x-ray machine that regulate the x-ray beam, including the timer, kilovoltage an milliamperage selectors
indirect theory
a theory suggesting that cell damage results from x-ray photons being absorbed with the cell, causing the formation of toxins, which, in turn, damage the cell
radiation absorbed dose (rad)
a unit for measuring absorbed dose; the traditional unit of dose equivalent to the gray (Gy)
body of the mandible
the horizontal, U-shaped portion of the mandible that extends from ramus to ramus
coronal plane
a vertical plane that divides the body into anterior and posterior sides; runs perpendicular to the ground
septum
bony wall or partition that divides a cavity into separate areas (appears radiopaque)
spatial resolution
a measurement of pixel size in multiplanar reconstruction
electromagnetic radiation
propagation of wavelike energy (without mass) through space or matter
lateral fossa
a smooth, depressed area of the maxilla located just inferior and medial to the infraorbital foramen between the maxillary canine and the lateral incisors (appears radiolucent)
temporomandibular joint (TMJ)
the jaw joint; includes the temporal bone and the mandible and the articular disc between the two bones
diagnostic radiograph
a radiograph that provides much information with images that have proper density and contrast, have sharp outlines, and are of the same shape and size as the object being radiographed
clinical attachment loss (CAL)
the measurement of bone loss; the measurement in millimeters of the distance between the cemento-enamel junction (CEJ) and the base of the sulcus or periodontal pocket
density
the overall darkness of an image
polychromatic x-ray beam
an x-ray beam containing many different wavelengths of varying intensities
impulse
a measure of exposure time (60 impulses occur in 1 second)
exposure incident
a specific incident involving contact with blood or other potentially infectious materials that results from procedures performed by the dental professional
milliamperage
in radiography, the quantity of x-rays emitted from the tubehead; measured in milliamperes
irregular radiopacities
terms used to describe a radiopacity that has irregular borders and is not well defined
copper stem
a portion of the anode that dissipates heat away from the tungsten target
foramen
an opening or hole in bone that permits the passage of nerves and blood vessels (appears radiolucent)
rotation center
in panoramic radiography, the axis or pivotal point on which the receptor and the x-ray tubehead rotate around the patient
positive vertical angulation
the positioning of the position-indicating device in a vertical, or up and down, plane
inverse square law
a rule that states that “the intensity of radiation is inversely proportional to the square of the distance from the source of radiation” (as distance is increased, radiation intensity at the object is decreased, and vice versa)
extraoral image
an image that results when a receptor is placed outside the mouth and exposed to x-rays to be used to examine large areas of the skull or jaws
interproximal incipient caries
caries found between two teeth that extends less than halfway through the thickness of enamel
gutta percha
claylike material used in endodontic therapy to fill the canals of the pulp (appears radiopaque)
Sievert (Sv)
a unit of measurement equivalent to the rem
contrast resolution
the number of gray scale colors available to be chosen for each pixel in the image
digital subtraction
a method in digital radiography that reverses the gray scale as an image is being viewed, so that radiolucent images appear white and radiopaque images appear black
right angle
in geometry, an angle of 90 degrees formed by two lines perpendicular to each other
intersecting
cutting across or through
lipline
an artifact seen on a panoramic image formed by the positioning of the patent’s lips
overexposed image
an exposure error that results in a dark image, resulting from excessive exposure time, kilovoltage or milliamperage, or a combination of these factors
generalized bone loss
bone loss occurring evenly throughout the dental arches
bitewing receptor
a receptor used in the interproximal examination
voltage
the measurement of force that refers to the potential difference between two electrical charges
photon
a bundle of energy with no mass or weight that travels as a wave at the speed of light and moves through space in a straight line
quantity of an x-ray beam
the number of x-rays produced in a the dental x-ray unit and is controlled by milliamperage
object-receptor alignment
one of the influencing factors for image distortion that refers to the alignment of the tooth and receptor
(Less image distortion results when the tooth and the receptor are parallel to each other)
axial plane
a horizontal plane that divides the body into superior and inferior parts; runs parallel to the ground
multiplanar reconstruction (MPR)
the reconstruction of raw data into images when imported into viewing software to create three anatomic planes of the body
glossopharyngeal air space
the portion of the pharnyx located posterior to the tongue and oral cavity; on a panoramic image, it appears as a vertical radiolucent band superimposed over the ramus of the mandible
mount
to place in an appropriate setting for display or to study
torus (plural: tori)
a bony growth in the oral cavity
critical instrument
instruments that are used to penetrate soft tissue or bone and must be sterilized after each use
mental foramen
an opening or hole in bone located on the external surface of the mandible in the region of the mandibular premolars (appears radiolucent)
neutral atom
an atom that contains an equal number of protons and electrons
total filtration
the combination of the inherent filtration and added filtration in an x-ray machine
electromagnetic radiation
the propagation of wavelike energy through space or matter, accompanied by electric and magnetic fields (cosmic rays, gamma rays, x-rays, ultraviolet rays, visible light, infrared light, radar waves, microwaves, radio waves)
bloodborne pathogens
microorganisms present in blood that cause disease in humans
amperage
the number of electrons that pass through a conductor; the strength of an electrical current
floor of the nasal cavity
a bony plate formed by the palatal processes of the maxilla and the horizontal processes of the palatine bones (appears radiopaque)
somatic cells
all the cells in the body, with the exception of the reproductive cells
wavelength
the distance between the crest of one wave to the crest of the next wave; determines the energy and penetrating power of the radiation
low-level disinfectant
US Environmental Protection Agency (EPA)- registered chemical germicides labeled only as “hospital disinfectants” recommended for general housekeeping purposes
gray (Gy)
the unit for measuring absorbed dose
pterygomaxillary fissure
a narrow space or cleft that separates the lateral pterygoid plate and the maxilla (appears radiolucent)
soft palate
the posterior portion of the roof of the mouth separating the mouth and pharynx
panoramic receptor
receptor used in the panoramic examination to show a wide view of the maxilla and the mandible
charge-coupled device (CCD)
an image receptor found in the intraoral sensor
cone beam computer tomography (CBCT)
computer-assisted digital imaging that uses a cone-shaped x-ray beam to acquire information and present it in three dimensions
interproximal caries
caries found between two adjacent teeth
buccal caries
caries found on the buccal tooth surface
transformer
a device used to increase or decrease the voltage of incoming electricity
Rinn XCP instrument
a type of beam alignment devices that are used with the paralleling technique, including plastic bite blocks, plastic aiming rings and metal indicator arms
kilovolt (kV)
the unit of measurement for voltage
palate
roof of the mouth
exposure light
a component of the dental x-ray machine control panel that provides a visible signal when x-rays are produced
focal spot
the tungsten target of the anode that converts bombarding electrons into x-ray photons by concentrating the electrons and creating an enormous amount of heat
maximum permissible dose (MPD)
maximum dose equivalent that a body is permitted to receive in a specific period with little to no injury
sagittal plane
a vertical plane that divides the body into the right and left sides; runs perpendicular to the ground
occlusal technique
the method used to expose a receptor in the occlusal examination
lamina dura
the wall of the tooth socket that surrounds the root of a tooth (appears radiopaque)
radiation
a form of energy carried by waves or a stream of particles
internal resorption
a regressive alteration of tooth structure that occurs within the crown of a tooth (appears radiolucent)
localization technique
method used to locate the position of a tooth or object in the jaws
quality factor (QF)
a factor used for radiation protection purposes that accounts for the exposure effects of different types of radiation (QF = 1)
risk
the likelihood of adverse effects or death resulting from an exposure to a hazard
tooth-bearing areas
regions of the maxilla and mandible in which the human dentition are normally located
critical organ
an organ that, if damaged, diminishes the quality of an individual’s life (skin, thyroid gland, lens of the eye, bone marrow)
absorption
the total transfer of energy from the x-ray photon to the atom of matter through which the x-ray beam passes
(Absorption depends on the energy of the x-ray beam and the composition of the absorbing matter or tissue)
alveolar bone
bone of the maxilla and the mandible that supports and encases the roots of the teeth (appears radiopaque)
metallic restoration
restorations that completely absorb x-rays, resulting in little to no radiation contacting the receptor so that the radiographic appearance is totally opaque (amalgam, gold)
periapical receptor
an intraoral receptor used to examine the entire tooth and supporting bone
hamulus
a small, hooklike projection of bone that extends from the medial pterygoid plate of the sphenoid bone (appears radiopaque)
filtration
the use of absorbing materials (aluminum) for removing the low-energy x-rays from the primary beam
exposure factors
factors that influence the density of a radiograph (milliamperage, kilovoltage, exposure time)
occlusal surfaces
the chewing surfaces of the posterior teeth
external auditory meatus
a hole or opening in the temporal bone located superior and anterior to the mastoid process
external resorption
a regressive alteration of a tooth structure that occurs along the periphery of the root surface
dental radiographer
any person who positions, exposes, and processes dental x-ray image receptors
direct current (DC)
a current in which electrons flow in one direction
radiation leakage
any radiation, with the exception of the primary beam, that is emitted from the dental tubehead
alveolar process
portion of the mandible that encases and supports teeth
total dose
the quantity of radiation received or the total amount of radiation energy absorbed
periodontium
tissues that support teeth (gingiva, alveolar bone)
subject contrast
the characteristics of the subject that influence radiographic contrast, including thickness, density, and composition of the subject
angle of the mandible
area of the mandible where the body meets the ramus
suture
an immovable joint that represents a line of union between adjoining bones of the skull (appears radiolucent)
lingual caries
caries found on the lingual tooth surface
image receptor
a recording medium
dentin
the tooth layer found beneath the enamel and surrounding the pulp cavity (appears radiopaque)
recurrent caries/secondary caries
caries found adjacent to a pre-existing restoration
sterilzation
the act of sterilizing
temporomandibular joint tomopgraphy
an extraoral radiographic technique used to examine the temporomandibular joint
periapical examination
a radiographic inspection used to examine the entire tooth and supporting bone
alternating current (AC)
a current in which electrons flow in opposite directions
frankfort plane
the imaginary plane that intersects the orbital rim of the eye and the opening of the ear
nucleus
the central, positively charged core of an atom, composed of protons and neutrons
standard precautions
measures that integrate and expand the elements of universal precautions in a standard of care designed to protect health care personnel and patients from pathogens that can be spread by blood r any other bodily fluid, excretion, or secretion
cell differentiation
individual characteristics of a cell that determine the response of the cell to radiation exposure
exposure button
a component of the dental x-ray machine control panel that activates the dental x-ray machine to produce x-rays
high contrast
a term describing an image with many very dark areas and very light areas and few shades of gray
multilocular
a term used to describe a radiolucent lesion that exhibits multiple compartments
herringbone pattern
an image on a dental radiograph that has been placed in the mouth backward and exposed
kilovoltage peak (kVp)
the maximum voltage that is used during an x-ray exposure
nutrient canal(s)
a tiny tubelike passageway through bone which contain blood vessels and nerves to supply maxillary teeth and interdental areas (appears radiolucent)
bitewing receptor
an intraoral receptor used to examine the crowns of both maxillary and mandibular teeth on one image
periapical lesion
a lesion located around the apex of a tooth
ground glass
a term used to describe a radiopacity, referring to a granular, pebbled or pulverized-glass appearance of bone that resembles pulverized glass
Digital Imaging and Communications in Medicine (DICOM) Data
the universal format for handling, storing and transmitting three-dimensional images
radiography
the art and science of making radiographs by the exposure of film to x-rays
underexposed image
an exposure error that results in a light image, as a result of inadequate exposure time, kilovoltage, milliamperage or a combination of these factors
focal spot size
the size of the tungsten target of the anode; determined by the manufacturer of the x-ray machine
matter
anything that occupies space and has mass
long-scale contrast
a term describing an image with many densities, or many shades of gray, resulting from the use of a higher kilovoltage range
intraoral receptor
a receptor placed inside the mouth during x-ray exposure and are used to examine the teeth and supporting structures
maxillary topographic occlusal projection
a type of occlusal projection used to examine the palate and anterior teeth of the maxilla
short-term effects
effects of radiation that appear within minutes, days, or weeks and are associated with large amounts of radiation absorbed in a short time
magnification
a geometric characteristic that refers to a radiographic image that appears larger than the actual size of the object it represents; influenced by target-film distance and object-receptor distance
intermediate-level disinfectant
US Environmental Protection Agency (EPA)-registered chemial germicides labeled only as “hospital disinfectants” and “tuberculocidals” recommended for all surfaces that have been contaminated
standard of care
the quality of care that is provided by dental practitioners in a similar locality under the same or similar conditions
intraoral radiographic examination
a radiographic inspection of teeth and adjacent intraoral structures
beta particles
fast-moving electrons emitted from the nucleus of radioactive atoms
bisect
to divide into two equal parts
receptor placement
the specific area where the receptor must be positioned before exposure
three-dimensional volume rendering
a three-dimensional shape that is created from two-dimensional images
cathode ray
a stream of high-speed electrons that originates from the cathode in an x-ray tube
tuberosity
a rounded prominence of bone (appears radiopaque)
inter-radicular
between the roots of adjacent teeth
calculus
a stonelike concretion that forms on the crowns and roots of teeth as a result of the calcification of bacterial plaque (appears radiopaque)
occlusal receptor
receptor used in the occlusal examination
periodontal
around a tooth
mental ridge
a linear prominence of cortical bone located on the external surface of the anterior portion of the mandible (appears radiopaque)
milliampere-second (mAs)
a unit of radiographic exposure equal to the product of milliamperage and exposure time
fossa
a broad, shallow, depressed area of bone (appears radiolucent)
background radiation
a form of ionizing radiation that ubiquitous in the environment (cosmic and terrestrial radiation)
recovery period
the period during which cellular damage caused by radiation is followed by repair
proton
a positively charged particle with a mass of 1
dentino-enamel junction (DEJ)
the junction between the dentin and enamel of a tooth
styloid process
a long, pointed, and sharp projection of bone that extends downward from the inferior surface of the temporal bone and is located anterior the mastoid process
indicator light
a component of the dental x-ray machine control panel that, when illuminated, indicates that the dental x-ray machine is turned on
occlusal examination
a type of intraoral radiographic examination used to inspect large areas of the maxilla or mandible on one image
cathode
the negative electrode in the x-ray tube that consists of a tungsten wire filament in a molybdenum cup; supplies the electrons necessary to generate x-rays
dose rate
the rate at which exposure radiation occurs and absorption takes place (dose rate = dose/time)
coherent scatter/unmodified scatter
one of the interactions of x-radiation with matter in which the path of a low-energy x-ray photon interacts with an outer-shell electron; no change in the atom occurs and an x-ray photon of scattered radiation is produced
negligence
omission or failure to provide reasonable precaution, care, or action that occurs when the diagnosis made or the dental treatment provided falls below the standard of care
voxel/three-dimensional pixel
the smallest element of a three-dimensional image
tungsten filament
a portion of the anode in the x-ray tube that serves as a focal spot and converts bombarding electrons into x-ray photons
periodontal abscess
a lesion that originates in a soft tissue pocket and is characterized by the accumulation of pus and destruction of bone (appears radiolucent)
endodontics
a branch of dentistry dealing with the diagnosis and treatment of diseases of the dental pulp
vertical bone loss
bone loss that does not occur in a plane parallel to the cemento-enamel junctions of adjacent teeth
interproximal examination
a radiographic inspection used to examine the crowns of both maxillary and mandibular teeth on a single image
focal opacity
a term used to describe a well-defined, localized radiopaque lesion
canal
a tubelike passageway through bone that houses nerves and blood vessels (appears radiolucent)
maxillary torus
a nodular mass of bone along the midline of the hard palate
collimation
the restriction of the size and shape of the x-ray beam in order to reduce patient exposure
labial mounting
a film mounting method in which radiographs are placed in the film mount to be viewed from the labial aspect of the oral cavity
general radiation/bremstrahlung/braking radiation
a form of radiation that occurs when speeding electrons slow down because of their interactions with the tungsten target in the anode
cell metabolism
the physical and chemical processes of a cell that determine the response of the cell to radation exposure
alveolar crest
the most coronal portion of the alveolar bone found between teeth; composed of dense cortical bone (appears radiopaque)
intraoral receptor
receptor placed inside the mouth to examine the teeth and supporting structures
multifocal confluent
a term used to describe multiple radiopacities that appear to overlap or flow together
lateral jaw projection- body of the mandible
an extraoral radiographic projection used to image the posterior body of the mandible in order to evaluate impacted teeth, fractures, lesion located n the body of the mandible
dental radiograph
two-dimensional representation of a three-dimensional object produced on an image receptor by the passage of x-rays through teeth and related supporting structures
horizontal bitewing
the bitewing receptor is placed in the mouth with the long portion of the receptor in a horizontal direction
trauma
injury produced by an external force
mixed lucent-opaque
a term used to describe a lesion that exhibits both radiolucent and radiopaque components
glenoid fossa
a concave area of the temporal bone on which the mandibular condyle rests
extraoral
outside the mouth
genetic cells
cells that contain genes; reproductive cells (ova, sperm)
nasal septum
a vertical bony wall or portion that divides the nasal cavity into the right and left nasal fossae (appears radiopaque)
exposure
a measure of ionization produced in air by x-radiation or gamma radiation
dentulous
with teeth; areas that exhibit teeth
mylohyoid ridge
a linear prominence of bone located on the internal surface of the mandible that extends from the molar region downward and forward toward the lower border of the mandibular symphysis (appears radiopaque)
anode
the positive electrode in the x-ray tube that consists of a wafer-thin tungsten plate embedded in a solid copper rod and converts electrons into x-ray photons
added filtration
aluminum discs inserted into the x-ray tubehead seal and collimator to absorb low-energy x-rays
field of view
the area that can be captured when performing imaging procedures
kilovoltage
in radiography, the x-ray tube peak voltage used during an exposure; measured in kilovolts
negative vertical angulation
the positioning of the position-indicating device above the occlusal plane that directs the central ray downward
sharpness
refers to the capability of the receptor to reproduce the distinct outlines of an object; influenced by focal spot size and movement
short-scale contrast
a term describing an image with only two densities resulting from the use of a lower kilovoltage range
occupational exposure
contact with blood or other infectious materials involving the skin, eye, or mucous membranes that results from procedures performed by the dental professional
alveolar bone loss
a loss of bone that surrounds and supports teeth in the maxilla or mandible
x-radiation
a high-energy radiation produced by the collusion of a beam of electrons with a metal target in an x-ray tube
sensor
a small detector in digital radiography that is placed intraorally to capture a radiographic image
coronoid notch
a scooped-out concavity of bone located distal to the coronoid process on the ramus of the mandible
x-ray beam angulation
one of the influencing factors for image distortion that refers to the direction of the x-ray beam
Waters projection
an extraoral radiographic projection used to evaluate the maxillary sinus area
direct theory
a theory that suggest that cell damage results when ionizing radiation hits critical areas directly within the cell
panoramic view
a wide view
pulpal sclerosis
a diffuse calcification of the pulp chamber and pulp canals of teeth that result in a decreased size of the pulp cavity (appears radiopaque)
mitotic activity
the process of cell division that determines the response of a cell to radiation exposure
occlusal caries
caries found on the chewing surfaces of posterior teeth
pixel
in digital electronic images, digital information is contained in, and presented as, discrete units of information
photoelectric effect
one of the interactions of x-radiation with matter, where the x-ray photon collides with a tightly bound, inner-shell electron and gives up all its energy to eject the electron from its orbit
scatter radiation
a form of secondary radiation the results from an x-ray beam that has been deflected from its path by the interaction with matter
quality assurance
special procedures used to ensure the production of high-quality, diagnostic radiographs
internal oblique ridge
a linear prominence of bone located on the internal surface of the mandible that extends downward and forward from the ramus (appears radiopaque)
pediatric occlusal projection
a type of occlusal projection used to examine the anterior teeth of the maxilla or mandible that is recommended for children aged 5 years or younger
latent image
the invisible image produced when the film is exposed to x-rays
contact areas
the area where adjacent tooth surfaces touch each other
exposure sequence
a definite order for periapical receptor placement and exposure that must be followed in the placement and exposure of intraoral films
enamel
the outermost radiopaque later of the crown of a tooth; the densest structure found in the human body
rule of isometry
a geometric principal that states “two triangles are equal if they have two equal angles and share a common side”
self-determination
the legal rights of an individual to make choices about the care they receive, including the opportunity to consent to or refuse treatment
superior foramina of the incisive canal
two tiny openings or holes in bone that are located on the floor of the nasal cavity (appear radiolucent)
movement
motion of the receptor or patient during radiographic exposure, resulting in a radiographic image with less sharpness
electrical current
the flow of electrons through a conductor used to produce x-rays
neutral atom
an atom that contains an equal number of protons and electrons
full mouth series
an intraoral series of dental radiographs that show all the tooth-bearing areas of the upper and lower jaws
radiosensitive cell
a cell that is sensitive to radiation (small lymphocytes, blood, reproductive bone, epithelial cells)
liable
accountable; legally obligated
condensing osteitis
a well-defined radiopacity seen below the apex of a nonvital tooth that has a history of long-standing pulpitis (appears radiopaque)
nasal cavity
a pear-shaped compartment of bone located superior to the maxilla (appears radiolucent)
nonstochastic effects
somatic effects that have a threshold and increase in severity with increasing absorbed dose
open contacts
on a dental radiograph, open contacts appear as a thin radiolucent line between adjacent tooth surfaces
ionizing radiation
radiation that is capable of producing ions by removing or adding an electron to an atom; classified into two groups: particulate radiation and electromagnetic radiation
extension arm
a part of the dental x-ray machine that suspends the x-ray tubehead and houses the electrical wires that extend from the control panel to the tubehead
horizontal angulation
the positioning of the position-indicating device and direction of the central ray in a horizontal, or side-to-side, plane
finger-holding method
a method of exposing receptors in which the patient’s finger or thumb stabilizes the receptor from behind the teeth
radiation biology
the study of the effects of ionizing radiation on living tissues
horizontal bone loss
bone loss that occurs in a plane parallel to the cemento-enamel junctions of adjacent teeth
extrusion
the abnormal displacement of teeth out of bone
pulp stones
calcifications found in the pulp chamber of pulp canals of teeth (appear radiopaque)
incisive canal
a passageway through bone that extends from the superior foramina of the incisive canal to the incisive foramen
coulomb (C)
a unit of electrical charge; the quantity of electrical charge transferred by 1 ampere in 1 second
forshortened images
images of teeth that appear too short with blunted roots
diagnosis
identification of a disease by examination or analysis
cortical/compact bone
the dense outer layer of bone (appears radiopaque)
endodontia
within a tooth
mandibular cross-sectional occlusal projection
a type of occlusal projection used to examine the buccal and lingual aspects of the mandible and locate foreign bodies in the floor of the mouth (salivary stones)
stochastic effects
biologic effects from radiation that occur as a direct function of dose; the probability of occurrence increases with increasing absorbed dose, however, the severity of effects does not depend on the magnitude of absorbed dose
direct digital imaging
a method of obtaining a digital image in which an intraoral sensor is exposed to x-radiation to capture a radiographic image that can be viewed on a computer monitor
tubehead seal
the aluminum or leaded-glass covering of the tubehead that permits the exit of x-rays from the tubehead, seals the oil in the tubehead, and filters the x-ray beam
storage phosphor imaging
a method of obtaining a digital image in with the image is recorded on a phosphor-coated plate and then placed into an electronic processor, where a laser scans the plate and produces an image on a computer
x-ray(s)
a beam if energy that has the power to penetrate substances and record image shadows on photographic film or digital sensors
cephalostat
a device in extraoral radiography that includes a receptor holder and head positioner that allow the dental radiographer to position both the receptor and patient easily
ionizing radiation
radiation capable of producing ions (particulate or electromagnetic radiation)
pericoronal
around the crown of a tooth
tubehead
the tightly sealed metal housing that contains the dental x-ray tube; includes the metal housing, insulating oil, tubehead seal, x-ray tube, transformers, aluminum discs, lead collimator, and position-indicating device; also contains a filament used to produce electrons and a target used to produce x-rays
perpendicular
intersecting at or forming right angles
pathologic resorption
resorption of a tooth not associated with the normal shedding of a deciduous tooth
aluminum discs
discs or sheets of aluminum, usually 0.5mm thick, that are placed in the path of x-ray beam to filter out the nonpenetrating, longer-wavelength x-rays
step-down transformer
a device used to decrease the incoming voltage from 110 or 220 volts to the low voltage required (usually 3 to 5 volts)
lateral pterygoid plate
a wing-shaped bony projection of the sphenoid bone located distal to the maxillary tuberosity region
infraorbital foramen
a hole or opening in bone found in the inferior border of the orbit
parenteral exposure
contact with blood or other infectious materials that results from piercing or puncturing the skin barrier
intrusion
the abnormal displacement of teeth into bone
filament circuit
regulates the flow of electrical current to the filament of the x-ray tube and is controlled by the milliampere settings
radioactivity
the process by which certain unstable atoms or elements undergo spontaneous disintegration or decay, in an effort to attain a more balanced nuclear state
fracture
the breaking of a part (appears as a thin radiolucent line)
risk management
the policies and procedures that the dental professional should follow to reduce the chance that a patient will take legal action against the dental professional or the supervising dentist
forshortening
a term describing images of teeth that appear too short as a result of excessive vertical angulation
nonmetallic restoration
restorations that do not completely absorb x-rays and vary in radiographic appearance from slightly radiopaque to radiolucent, depending on the density of the material (porcelain, composite, acrylic)
characteristic radiation
a form of radiation that occurs when a high-speed electron dislodges from an inner-shell electron from an atom, causing ionization of the atom
asepsis
the absence of pathogens or disease-causing microorganisms
palatoglossal air space
refers to the space found between the palate and the tongue; on a panoramic image, it appears as a horizontal radiolucent band located superior to the apices of the maxillary teeth
contrast
how sharply dark and light areas are differentiated on an image; the difference in the degrees of densities between adjacent areas on a dental radiograph
digitize
in digital radiography, to convert an image into digital form that can, in turn, be processed by a computer
beam alignment device
a device used to align the position-indicating device in relation to tooth and receptor that positions the intraoral receptor in the mouth and retains the receptor in position during exposure; helps stabilize the receptor in the mouth and reduce the chance of movement, thus reducing the patient’s exposure to x-radiation
submandibular fossa
a depressed area of bone located on the internal surface of the mandible inferior to the mylohyoid ridge (appears radiolucent)
ALARA concept
a concept of radiation protection that states that all exposure to radiation must be kept to a minimum, or “as low as reasonably achieveable”
line pairs (lp)/millimeter (mm)
a measurement used to evaluate the ability of the computer to capture the resolution or detail of the radiographic image
cell
the basic structural unit of living organisms
total dose
quantity of radiation received, or the total amount of radiation energy absorbed
intensity
the total energy of the x-ray beam; the product of the quantity (number of x-ray photons) and quality (energy of each photon) per unit area time of exposure
grid
a device used in extraoral imaging used to prevent scatter radiation from reaching the receptor during exposure
somatic effects
radiation injuries that produce changes in somatic cells and produce poor health in the irradiated individual (cancer, leukemia, cataracts)
thermionic emission
the release of electrons from the tungsten filament when the electrical current passes through it and heats the filament
half-value layer (HVL)
the thickness of material that when placed in the path of the x-ray beam, reduces the exposure by one-half
genial tubercles
tiny bumps of bone located on the lingual aspect of the mandible in the anterior region (appear radiopaque)
caries
tooth decay caused by microorganisms (appears radiolucent)
median palatal suture
the immovable joint between the two palatine processes of the maxilla (appears radiolucent)
analog image
a radiographic image produced by conventional film
receptor contrast
the characteristics of the receptor that influence radiographic contrast that includes the inherent qualities of the receptor and receptor processing and the qualities of the sensor
personal protective equipment (PPE)
equipment work by dental professionals to protect themselves from hazards, including gloves, mask, and eyeware
mandibular condoyle
a rounded projection of bone extending from the posterosuperior border of the ramus of the mandible
energy
what occurs when matter is altered
submentovertex projection
an extraoral radiographic projection used to identify the position of the condoyles, demonstrate the base of the skull and evaluate fractures of the zygomatic arch
Roentgen equivalent in man (rem)
the traditional unit of the dose equivalent; the product of absorbed dose (rad) and a quality factor (QF) specific for the type of radiation
three-dimensional digital imaging
an image that demonstrates structures in three dimensions
phalangioma
a error on a dental radiograph the refers to the distal phalanx of the finger seen on the radiograph, as a result of the finger-holding method with the bisecting technique
metal housing
the metal body of the dental x-ray tubehead that surrounds the x-ray tube and trasnformers
cavity
a hole in a tooth that results from the caries process (appears radiolucent)
insulating oil
oil that surrounds the x-ray tube and transformers inside the tubehead
object-receptor distance
one of the influencing factors of image magnification that refers to the distance between the object being radiographed and the receptor
high-voltage circuit
the circuit that provides the high voltage required to accelerate electrons and to generate x-rays in the x-ray tube; controlled by the kilovoltage settings
pulp cavity
a cavity within a tooth that includes both the pulp chamber and pulp canals, containing blood vessels, nerves, and lymphatics (appears radiolucent)
radiograph
a two-dimensional representation of a three-dimensional object
central ray
the central portion of the primary beam of x-radiation
dose-response curve
a curve that can be used to correlate the “response,” or damage of tissues with the “dose,” or amount of radiation received
uvula
a small, muscular structure located on the free edge of the soft palate
unilocular corticated
a term used to describe a radiolucent lesion that exhibits one compartment with a well-defined outer border
lead apron
a flexible lead shield used to protect the patient’s reproductive and blood-forming tissues from scatter radiation
radiology
the science or study of radiation as used in medicine, dealing with the use of x-rays, radioactive substances, and other forms of radiant energy in the diagnosis and treatment of disease
high-level disinfectant
chemicals classified by the US Environmental Protection Agency (EPA) as “sterilants-disinfectants” to be used to disinfect heat-sensitive, semicritical dental instruments
quality control tests
specific tests designed to maintain and monitor dental x-ray equipment, supplies and processing
periapical cyst
a lesion characterized by an epithelial-lined cavity or sac located around the apex of a nonvital tooth that results from pulpal death (appears radiolucent)
mandibular canal
a tubelike passageway through bone that travels the length of the mandible (appears radiolucent)
lingula
a small, tongue-shaped projection of bone seen adjacent to the mandibular foramen
Compton scatter
one of the interactions of x-radiation with matter in which the x-ray photon collides with a loosely bound, outer-shell electron and gives up part of its energy and continues in a different direction at a lower energy level
bitewing tab
a heavy paperboard tab or loop fitted around an intraoral receptor and used to stabilize the receptor during the exposure
latent period
the amount of time that elapses between exposure to ionizing radiation and the appearance of observable clinical signs on the radiograph
particulate radiations
tiny particles of matter that possess mass and travel in straight lines at high speeds
posterior teeth
premolars and molars
overlapped contacts
the area on a dental image where the contact area of one tooth is superimposed over the contact area of an adjacent tooth
lead collimator
a lead diaphragm or tubular device used to restrict the size and shape of the x-ray beam
maximum accumulated dose (MAD)
the maximum accumulated lifetime radiation dose that may be received by persons who are occupationally exposed to radiation
digital imaging
a filmless imaging system that captures a radiographic image using a sensor and breaking it into electronic pieces, and presenting and storing the image electronically
volt (V)
unit of measure for voltage
cumulative effects
the additive effects of repeated radiation exposure
Reverse Towne projection
an extraoral radiographic projection used to identify fractures of the condylar neck and ramus area
indirect digital imaging
a method of obtaining a digital image in which an existing radiograph is scanned and converted into digital form using a charge-coupled device camera
mental fossa
a scooped-out depressed area of bone located on the external surface of the anterior mandible (appears radiolucent)
disinfect
to inhibit or destroy disease-causing microorganisms through use of a chemical or physical procedure
periodontal ligament space (PDL)
a space that exists between the root of a tooth and the lamina dura, which contains connective tissue fibers, blood vessels, and lymphatics (appears radiolucent)
paralleling technique
an intraoral radiographic technique used to expose periapical receptors where the receptor is placed parallel to the long axis of the tooth, the central ray is directed perpendicular to the receptor and the long axis of the tooth and a beam alignment device must be used to keep the receptor parallel to long axis of the tooth
velocity
speed; in dental radiography, the speed of a wave
scale of contrast
the range of useful densities seen on a dental image
filament current/low-voltage circuit
the circuit that regulates the flow of electrical current to the filament of the x-ray tube; controlled by the milliampere settings
zygomatic process of the maxilla
a bony projection of the maxilla that articulates with the zygoma (appears as a J-shaped or U-shaped radiopacity on a maxillary molar periapical image)
circuit
a path of electrical current
image interpretation
an explanation of what is viewed on a dental radiograph; the ability to read what is revealed by a dental radiograph
elongated images
images on a dental radiograph that appear long and distortede
intraoral
inside the mouth
infectious waste
waste that consists of blood, bloodborne pathogens, contaminated sharps, or other microbiologic products
incisive foramen
an opening or hole in bone located at the midline of the anterior portion of the hard palate directly posterior to the maxillary central incisors (appears radiolucent)
target-receptor distance
one of the influencing factors of image magnification that refers to the distance between the source of x-rays and the receptor
rampant caries
caries that affects numerous teeth in the dentition
posteroanterior projection
an extraoral radiographic projection of the skull used to evaluate facial growth, trauma, diseases, and developmental abnormalities
leaded-glass housing
leaded-glass vacuum tube that prevents x-rays from escaping in all directions
mass
weight; the physical volume or bulk of a solid body
milliampere (mA)
a unit of measurement used to describe the intensity of an electrical current (1/1000 of an ampere)
zygoma/zygomatic bone
the cheekbone (appears as a diffuse radiopaque band posterior to the zygomatic process of the maxilla)
process
a marked prominence or projection of bone (appears radiopaque)
rectification
the conversion of alternating current to direct current
quality of an x-ray beam
the mean energy or penetrating ability of the x-ray beam that is controlled by the kilovoltage
localized bone loss
bone loss occurring in isolated areas
mastoid process
a marked prominence of bone located posteroinferior to the temporomandibular joint
vacuum tube
a sealed glass tube from which most of the air has been evacuated
statute of limitations
a period in which a patient may bring a malpractice action against a dentist or an auxillary
nucleon
part of an atomic nucleus (protons, neutrons)
inverted Y
a radiographic landmark that represents the intersection of the maxillary sinus and the nasal cavity (appears radiopaque)
edentulous
a patient without teeth
radiopaque
the portion of an image that is light or white due to the structure resisting the passage of the x-ray beam and limiting the amount of x-rays that reach the receptor
extraoral imaging
a radiographic inspection of large areas of the skull or jaws that requires the use of extraoral imagine receptors
pediatric dentistry
a branch of dentistry dealing with the diagnosis and treatment of dental diseases in children
focal trough
a three-dimensional curved zone in which structures are clearly demonstrated on a panoramic image (a patient must be positioned so that the dental aches are located within the focal trough area)
transcranial projection
an extraoral radiographic projection used to evaluate the superior surface of the condoyle and the articular eminence; can also be used to evaluate the movement of the condoyle when the mouth is open
pulpal obliteration
total calcification of the pulp cavity (appears radiopaque)
buccal object rule
governs the orientation of structures portrayed in two images exposed at different angulations; used to determine the buccal-lingual relationship of an object
underexposed film
an exposure error that results in a light film due to inadequate exposure time, kilovoltage, milliamperage, or a combination of these factors
avulsion
the complete displacement of a tooth from the alveolar bone
primary radiation/primary beam/useful beam
the penetrating x-ray beam produced at the target of the anode and the exits the tubehead
sinus
a hollow space, cavity, or recess in bone (appears radiolucent)
pathogen
a microorganism capable of causing disease
interproximal
between two adjacent surfaces
maxillary sinuses
paired compartments of bone located within the maxilla and located superior to the maxillary posterior teeth (appears radiolucent)
collimator/collimating device
a diaphragm, usually made of lead, used to restrict the size and shape of the x-ray beam
sclerotic bone/osteosclerosis
a well-defined radiopacity seen below the apices of vital, noncarious teeth
right-angle technique
a localization technique in which the structures can be seen in two radiographs (one periapical and one occlusal)
stepwedge
a device constructed of uniform-layered thickness of an x-ray absorbing material (usually aluminum) to absorb varying amounts of x-rays and are used to demonstrate film densities and contrast scales
lingual foramen
an opening or hole in bone located on the internal surface of the mandible near the midline (appears radiolucent)
periapical
around the apex of a tooth
articular eminence
a rounded projection of of the temporal bone located anterior to the glenoid fossa
penumbra
the fuzzy, unclear area that surrounds a radiographic image
physiologic resorption
resorption of teeth associated with the normal shedding of a deciduous tooth
angle
in geometry, a figure formed by two lines diverging from a common point
molybdenum cup
a portion of the cathode in the x-ray tube that focuses electrons into a narrow beam and directs the beam across the tube toward the tungsten target in the anode
receptor
something that responds to a stimulus; a recording medium (x-ray film, digital sensors)
high-voltage circuit
provides the high voltage required to accelerate electrons and to generate x-rays in the x-ray tube; controlled by the kilovoltage settings (65,000-100,000 volts)
complementary metal oxide semiconductor (CMOS)/active pixel sensor (APS)
silicon-based detector used in digital imaging that differs from the charge-coupled device (CCD) in the way that the pixels are read
lateral cephalometric projection
an extraoral image that is used to determine facial growth and development, trauma, disease, and developmental abnormalities
nanometer
a measurement used for wavelength
exposure time
the interval during which x-rays are produced
alpha particles
a type of particulate radiation emitted from the nuclei of heavy metals; contain two protons and two neutrons are are positively charged
low contrast
a term describing an image with many shades of gray and few areas of black and white
bit-depth image
the number of possible gray-scale combinations for each pixel
mandibular topographic occlusal projection
a type of occlusal projection used to examine the anterior teeth of the mandible
distortion
a geometric characteristic that refers to a variation in the true size and shape of the object being radiographed; influenced by object-receptor alignment and x-ray beam angulation
compton electron
an outer-shell electron that is ejected from the its orbit during Compton scatter; carries a negative charge
parallel
moving or lying in the same plane; always separated by the same distance and not interacting
image
a picture or likeness of an object
atom
a tiny, invisible particle that is the fundamental unit of matter
panoramic imaging
an extraoral technique used to examine the upper and lower jaws on a single projection
vertical bitewing
the bitewing receptor is placed in the mouth with the long portion of the receptor in a vertical direction
tomography
radiography technique that allows the imaging of one layer or section of the body while blurring images from structures in other planes
dose
the amount of energy absorbed by tissue
long axis of a tooth
an imaginary line that divides a tooth longitudinally into two equal halves
long-term effects
effects of radiation that appear years, decades, or generations after exposure and are associated with small amounts of radiation absorbed repeatedly over a long period
electricity
the energy used as a source of power to make x-rays
lingual mounting
a film mounting method in which radiographs are placed in the film mount to be viewed from the lingual aspect of the oral cavity
dose equivalent
a measurement used to compare the biologic effects of different types of radiation
tubercle
a small bump or nodule of bone (appears radiopaque)
radioresistant cell
a cell that is resistant to radiation (bone, muscle, nerve cells)
kinetic energy
energy of motion
sharp
any object that can penetrate skin, including, but not limited to, needles and scalpels
luxation
the abnormal displacement of a tooth
malpractice
improper or negligent conduct or treatment
target lesion
a well-defined, localized radiopacity surrounded by a uniform radiolucent halo
root surface caries
caries found on the roots of teeth
periapical abscess
a lesion characterized by a localized collection of pus around the apex of a nonvital tooth that results from pulpal death (appears radiolucent)
hard palate
the bony plate that separates the nasal cavity from the oral cavity in the anterior portion of the roof of the mouth
anterior nasal spine
a sharp projection of the maxilla located in the anteroinferior portion of the nasal cavity (appears radiopaque)
anterior teeth
incisors and canines
disclosure
in dental radiography, the process of informing a patient about the particulars of exposing dental radiographs
Roentgen (R)
the traditional unit of exposure for x-rays
lateral jaw projection- ramus of the mandible
an extraoral radiographic projection used to image the ramus of the mandible in order to evaluate impacted third molars, large lesions, and fractures that extend into the ramus of the mandible
coronoid process
a marked prominence of bone located on the anterior ramus of the mandible (appears radiopaque)
ion
an electrically unbalanced particle; an atom that gains or loses an electron
informed consent
consent given by a patient following complete disclosure about the particulars of a procedure
tungsten filament
a coiled wire of tungsten in the cathode in the x-ray tube that produces electrons when heated
inherent filtration
occurs when the primary beam passes through the glass window of the x-ray tube, the insulating oil, and the tubehead seal
mandibular foramen
a round or ovoid hole in bone on the lingual aspect of the ramus of the mandible
incipient
small; beginning to exist or appear
inferior border of the mandible
a linear prominence of cortical bone that extends from the lateral walls of the nasal cavity (appears radiopaque)
maxillary lateral occlusal projection
a type of occlusal projection used to examine the palatal roots of molar teeth and locate foreign bodies or lesions in the posterior maxilla
disinfection
the act of disinfecting
position-indication device (PID)
an open-ended, lead-lined cylinder extending from the opening of the metal housing of the tubehead, used to aim and shape the beam
bisecting technique
an intraoral radiographic technique used to expose periapical receptors
the receptor is placed along the lingual surface of the tooth, the central ray of the x-ray beam is directed perpendicular to the imaginary bisector formed by the receptor and the long axis of the tooth
cone-cut
a clear, unexposed area of a dental radiograph that occurs when the position-indicating device is misaligned and the x-ray beam is not centered over the film
autotransformer
a voltage compensator that corrects for minor fluctuations in the current flowing through the x-ray machine
imaginary bisector
an imaginary plane that divides in half the angle formed by the receptor and the long axis of the tooth; creates two equal angles and provides a common side for the two imaginary equal triangles
uniocular noncorticated
a term used to describe a radiolucent lesion that exhibits one compartment without a well-defined outer border
angulation
the alignment of the central x-ray beam in the horizontal and vertical planes
step- up transformer
a device used to increase the incoming line voltage from 110 or 220 volts to the high voltage required (usually 65,000 to 100,000 volts)
inferior nasal conchae
wafer-thin, curved plates of bone that extend from the lateral walls of the nasal cavity (appears radiopaque)
period of injury
occurs after the latent period following exposure to radiation and can include a variety of cellular injuries
cancellous
the soft, spongy bone located between two layers of dense cortical bone (appears radiolucent)
film mounting
the arrangement of radiographs in anatomic order
periapical receptor
receptor used in the periapical examination
electron
a tiny negatively charged particle found outside of the nucleus in the atom
pediatric patient
a child patient
genetic effects
effects of radiation that are not seen in the person irradiated but are passed on to future generations through genetic cells
ramus
vertical portion of the mandible that is found posterior to the third molar (one rami on each side)
mandibular torus
a bony growth seen along the lingual aspect of the mandible
liability
legal accountability
occlusal receptor
a receptor used to examine large areas of the maxilla or the mandible where the patient occludes on the entire receptor
sterilize
the use of a physical or chemical procedure to destroy all pathogens, including highly resistant bacterial and fungal spores
extraoral receptor
receptor placed outside the mouth to examine large areas of the skull or jaws
subject thickness
the thickness of soft tissue and bone in a patient
antiseptic
a substance that inhibits the growth of bacteria
maxillary tuberosity
a rounded prominence of bone that extends posterior to the third molar region (appears radiopaque)
edentulous zone
areas where teeth are no longer present
periodontal disease
a group of diseases that affects the tissues around teeth
cavitation
a hole or cavity in a tooth that results from the caries process (appears radiolucent)
midsagittal plane
an imaginary line or plane passing thought the center of the body that divides it into right and left halves
frequency
the number of wavelengths that pass a given point in a certain amount of time and indicates the energy of radiation
ridge
a linear prominence or projection of bone (appears radiopaque)
elongation
a term used in radiography to describe the images of teeth that appear longer than the actual teeth, as a result of insufficient vertical angulation
protective barrier
a barrier of radiation-absorbing material used to protect the operator from the primary and scatter radiation (a wall)
neutron
an electrically neutral or uncharged particle
radiolucent
the portion of an image that is dark or black due to the structure readily permitting the passage of the x-ray beam to allow more x-rays to reach the receptor
ghost image
an artifact on a dental radiograph produced when a radiodense object (earring) is penetrated twice by the x-ray beam (appears radiopaque)
soft tissue opacity
a well-defined radiopacity located in the soft tissue and viewed on a radiograph
nasopharyngeal air space
refers to the portion of the pharynx located posterior to the nasal cavity; on a panoramic image, it appears as a diagonal radiolucency located superior to the radiopaque shadow of the soft palate and uvula
head positioner
one of the component parts of a panoramic unit consisting of a chin rest, notched bite block, forehead rest, and lateral head supports
anatomic order
the order in which teeth are arranged within the dental arches
digital image
an image composed of pixels
thyroid collar
a flexible lead shield used to protect the thyroid from scatter radiation
periapical granuloma
a lesion characterized by a localized mass of granulation tissue around the apex of a nonvital tooth (appears radiolucent)
x-ray tube
a component part of the x-ray tubehead that generate x-rays, including a leaded-glass vacuum tube, cathode, and anode
furcation area
the area between the roots of multi-rooted teeth
semicritical instrument
instruments that contact but do not penetrate soft tissue or bone and must be sterilized after each use
rampant
growing or spreading unchecked
secondary radiation
radiation created when the primary beam interacts with matter; less penetrating that primary radiation
cone-beam technology
a three-dimensional imaging technique that cone-shaped radiation beam to acquire a digital image
ampere (A)
the unit of measure used to describe the number of electrons passing through a conductor (electrical current strength)
film badge
a device used to measure and monitor radiation exposure; worn by persons frequently exposed to radiation
