Dental Radiography and Anatomy Review

Comprehensive practice flashcards covering dental radiography mounting, anatomical landmarks, radiation characteristics, and panoramic imaging based on lecture notes.

Labial mounting

A mounting method where the dot is up; the patient's right is the viewer's left. It is ADA approved.

Lingual mounting

A mounting method where the dot is depressed; the patient's right is viewed as the patient's right (viewed from the tongue).

Curve of Spee

The upward curve of the anatomy that helps in mounting bite-wing (BW) images.

Compact bone

Also known as cortical bone; it appears opaque on dental images.

Cancellous bone

Bone with a lattice-like structure that appears lucent on dental images.

Sinus

An empty space within the bone that appears lucent; located in the maxillary premolar and molar region.

Fossa

A hole or depression in the bone that appears lucent; examples include the maxillary canine and lateral incisor areas.

Foramen

An opening or hole in the bone that permits the passage of nerves and blood vessels, appearing lucent.

Suture

An immovable joint between two bones in the skull that appears lucent.

Septum

A bony wall or partition that divides two spaces or cavities, appearing opaque.

Anterior nasal spine

A V-shaped radiopaque area located at the intersection of the floor of the nasal cavity and the nasal septum.

"Y" formation

The radiopaque intersection of the maxillary sinus and the median palatal suture found in the maxillary canine region.

Genial tubercle

A radiopacity located below the central incisors on the mandible, surrounding the lingual foramen.

Mental ridge

A thick radiopaque area in the mandibular anterior region extending to the premolar area.

Nutrient canals

Vertical lucent lines most often seen in the anterior mandible.

Mental foramen

A lucent opening frequently misdiagnosed as a periapical granuloma or abscess.

Periodontal ligament (PDL)

A thin lucent area lying between the alveolar bone and the tooth.

Lamina dura

The radiopaque wall of the tooth socket.

Alveolar crest

In health, it measures $1.5$ to $2.0\,mm$ below the junction of the CEJ.

kVp (Kilovoltage peak)

Determines the quality, energy, or penetrating ability of the x-ray beam and influences wavelength.

mA (Milliamperage)

Determines the quantity or total number of x-rays produced.

Intensity

The product of the quantity (mA) and quality (kVp) per unit of area per time of exposure.

Voltage

The electrical potential difference between two electrical charges.

Ampere

The unit of measure used to describe the number of electrons, or current, flowing through the cathode filament.

Inverse square law

The intensity of radiation is inversely proportional to the square of the distance from the source; if FFD is doubled, the exposure time is quadrupled.

Density

The overall blackness or darkness of a dental image.

Contrast

The difference in degrees of blackness between adjacent areas on a dental image.

Scale of contrast

The range of useful densities seen on a dental image.

High contrast

An image with very dark areas and very light areas.

Low contrast

An image with many shades of gray.

Stepwedge

A device used to determine contrast made from aluminum with steps of $2\,mm$ increments.

Magnification

An image that appears larger than the actual size of the object.

Distortion

A variation in the true size and shape of the object being imaged.

Sharpness

The distinct outlines of an object on an image.

OFD (Object Film Distance)

The distance between the object and the receptor; also known as ORD (Object Receptor Distance).

FFD (Focal Film Distance)

The distance between the focal spot (target) and the receptor; also known as TRD (Target Receptor Distance).

Focal trough

A theoretical concept used in panoramic imaging to determine where the dental arches must be positioned to achieve the clearest image.

Ghost image

A radiopacity caused by objects left in or on the patient; it appears higher and larger than the actual object.

Reverse smile

A panoramic error caused by the patient's chin being tipped up.

Exaggerated smile line

A panoramic error caused by the patient's chin being tipped down.

Collimator (Panoramic)

A lead plate with a $1-2\,mm$ vertical narrow slit that restricts the size and shape of the x-ray beam.

Intensifying screens

Screens in a cassette holder used to reduce radiation; Green (rare earth) screens are $4\times$ faster than Blue (calcium tungstate) screens.