Dental Radiography Exam Notes

X-Radiation Exposure Reduction

  • The most effective method for reducing patient exposure to x-radiation is using a lead apron.

Maxillary Molar Area Radiograph

  • If there are no teeth to serve as guides, the tuberosity indicates a maxillary molar area radiograph.

Human Tissue Composition

  • Human tissues are mainly composed of water (H2OH_2O).

Wavelength Penetrating Power

  • Adjusting the kVp (kilovoltage peak) produces wavelengths with the greatest penetrating power.

Radiation Damage Susceptibility

  • Infants are the population most susceptible to radiation damage.

Tubehead Drift

  • When the tubehead drifts, the first step is to stop using the machine.

Radiation Types

  • Secondary radiation is formed by the interaction of x-rays with matter.

PID and Radiation

  • Patients receive less radiation when using a rectangular PID (Position Indicating Device).

Lead Apron and Thyroid Collar

  • The main purpose of using a lead apron with a thyroid collar is to protect the patient from scatter radiation.

Digital Images and Radiation

  • While exposing digital images, radiation deflecting off the patient's head is scatter radiation.

Radiation Injury Sequence

  • The sequence that best describes radiation injury to tissue is: Latent period, period of injury, period of recovery.

Somatic Effects of Radiation

  • Somatic effects of radiation do NOT have damaging effects on offspring.

Unnecessary Radiation Exposure

  • Radiograph technique errors may cause unnecessary radiation exposure to the patient.

Radiation Hazard to Operator

  • Scatter radiation poses the greatest hazard to the operator.

Measuring Radiation

  • Roentgen measures the amount of radiation that reaches the surface of the skin.

Maximum Permissible Dose (MPD)

  • The maximum permissible dose (MPD) of ionizing radiation for occupational exposure is 5.0 rem per year (0.05 Sv).

ALARA Principle

  • ALARA (As Low As Reasonably Achievable) is primarily concerned with artificial radiation.

Dental Assistant Protection

  • During patient exposure, protection from radiation for the dental assistant includes standing behind a wall.

Time Between Exposure and Damage

  • The time between patient exposure to radiation and the appearance of biological damage is the latent period.

Long-Term Effect of Radiation

  • Genetic defects are a long-term effect of radiation.

Factors Affecting X-ray Quantity

  • mA (milliamperage) affects the quantity of x-rays being emitted from the tubehead.

Protecting Patients from X-Radiation

  • The most important step a dentist can take in protecting patients from x-radiation is to properly prescribe radiographs.

Protecting Patients from Excess Radiation

  • Digital radiography can help to protect patients from excess radiation damage to tissues.

Penetrating X-ray Beam

  • The penetrating x-ray beam produced during dental radiography is called primary radiation.

Regulation of X-ray Equipment

  • The Federal Government regulates the manufacturing and installation of x-ray equipment.

Dental Assistant Responsibility

  • The most important responsibility of the dental assistant in dental radiography is implementing the ALARA principle.

Harmful Effects of Radiation

  • The process for the harmful effects of radiation is ionization.

Radiographs on Small Child

  • When taking radiographs on a small child who cannot hold the sensor intra-orally, the dental assistant should ask a parent or guardian to hold the sensor.

Aluminum Disc Purpose

  • The purpose of the aluminum disc in the x-ray tubehead is to filter out long wave x-rays from the primary beam.

Mandibular Posterior Landmarks

  • The internal oblique ridge is useful when mounting images of the mandibular posterior area.