Dental Radiology Final Exam Study Guide Questions And Answers Verified 100% Correct

Dental Radiology Final Exam Study Guide Questions And Answers Verified 100% Correct Words always associated with mA - ANSWER -Number, quantity, amount, density Milliamperage - ANSWER -cathode controls thermionic emissions Density - ANSWER -Darkness; amount of light transmitted through a film What is kVp? - ANSWER -Kilovoltage potential; circuit that controls the speed of electrons from cathode to anode 15% rule is always associated with what? - ANSWER -kVp Half Value Layer - ANSWER -Measurement of the quality of the energy in the primary beam What is the purpose of kVp circuitry? - ANSWER -Controls speed of electrons What is the filter? - ANSWER -2.5 mm thick; made of aluminum; filters long waves from primary beam What is a collimator? - ANSWER -Made of lead; has a hole; reduces the primary beam to 2 3/4 in. on the face What is rectification? - ANSWER -Blocking of the reversal of the alternation current. What is the Inverse Square Law? - ANSWER -The intensity of radiation/energy varies inversely with the square of the distance Contrast - ANSWER -Difference between densities 90 kVp= - ANSWER -Low contrast 60 kVp= - ANSWER -High contrast What principle is involved with increasing/decreasing the TFD? - ANSWER Inverse Square Law Increased mA= - ANSWER -Increase in Density Will penumbra be more visible in an exposure made with an 8" or a 16" cone? - ANSWER -8" What describes the proper direction of the CR in the Bis. angle technique? - ANSWER -90 degrees to the imaginary bisector line What describes the distance between the film and the tooth in the bis. angle technique? - ANSWER -The film is placed as close to the tooth as possible What is a variation of bisecting angle technique? - ANSWER -Occlusal radiography SLOB rule - ANSWER -Same on lingual, opposite on buccal What is the best way to image the maxillary sinus? - ANSWER -Maxillary left/right posterior topographic occlusal radiograph What is the direct effect? - ANSWER -Primary beam hits and alters cells in body tissue Indirect effect - ANSWER -Damage to tissues not in the path of the primary beam bc of ionization in molecules Thompson scatter - ANSWER -An atom absorbs some of the photon's energy; the photon continues with less energy; When the primary beam interacts with tissue in this manner, scatter radiation is produced What does Roentgen measure? - ANSWER -Amount in air What does RAD measure? - ANSWER -About in everything except air and man What does REM measure? - ANSWER -Radiation absorbed by man Ionizing radiation is - ANSWER -Linear and non-threshold Lethal dose of radiation - ANSWER -450 RAD General population dose of radiation - ANSWER -360 mRem Tissue most sensitive to radiation - ANSWER -WBC Tissue least sensitive to radiation - ANSWER -Nerve Cell What is the first sign of too much radiation? - ANSWER -Erythema (reddening of skin) MPD for a worker per year - ANSWER -5 rem MPD for a worker per week - ANSWER -100 mrem formula for figuring out MAD - ANSWER -(N-18)x5 REM RAD stands for what? - ANSWER -Radiation absorbed dose Reducing agents in the Developer - ANSWER -Elon= Density Hydroquinone= Contrast Activator in the Developer - ANSWER -Sodium Carbonate= Softens/swells emulsion Preservative in the Developer - ANSWER -Sodium sulfite= prevents oxidation/preserves life Restrainer in the Developer - ANSWER -Potassium Bromide= keeps film fog to a minimum Solvent in the Developer - ANSWER -H2O Is the Developer an acid or base? - ANSWER -Base Developer - ANSWER -RAPRS (Reducing agent, activator, preservative, restrainer, Solvent) Fixer - ANSWER -CHAPS (Clearing Agent, Hardener, Aceitic Acid, Preservative, and solvent)