Dentosphere : World of Dentistry

# A patient with pernicious anemia often consults the dentist for relief of: A. Edematous buccal mucosa B. Severe gingivitis C. Glossitis D. Denuded gingiva The correct answer is: C. Glossitis Pernicious anemia is a relatively common, chronic, progressive, megaloblastic anemia. It is caused by the lack of secretion of the intrinsic factor in normal gastric juice. This factor is necessary for adequate absorption of vitamin B12, which is necessary for the maturation of erythrocytes. As a result, they produce fewer erythrocytes than normal. The onset of pernicious anemia usually is insidious and vague. As the condition progresses, there will be a sore, painful tongue (atrophic glossitis), angular cheilitis, a tingling numbness of the extremities, difficulty swallowing (dysphagia), painful swallowing (odynophagia).  A Schilling 24-hour urine test is done to evaluate whether vitamin B 12 is being absorbed by the body and is most commonly used to evaluate patient...

# Which of the following interactions is responsible for the creating of Bremsstrahlung / Braking radiation? A. Electrons falling from the K shell to the J shell B. Interaction of electrons with electrons C. Conversion of photons into electrons D. Interaction of electrons with nuclei The correct answer is D. Interaction of electrons with nuclei. Bremsstrahlung radiation is created when high-speed electrons interact with the Tungsten nuclei at the target. The fast-moving electron loses kinetic energy when it interacts with the nuclei, converting the lost kinetic energy into a photon.

# The radiographic density of which of the following materials varies the MOST? A. Amalgam B. Soft tissue C. Composite D. Acrylic E. Gold The correct answer is C. Composite. The radiographic density of composites varies the most because the manufacturers may place a different amount of barium salts or other opaque filling materials. Metals like amalgam and gold appear with a standard amount of radiopacity. Acrylic typically does not possess any opaquers, and therefore is usually totally radiolucent. Soft tissue is fairly radiolucent.

# Which of the following is the reason intensifying screens are used with extraoral radiographic films? A. Improve the image quality B. Increase the exposure time C. Increase the kVp D. Decrease the radiation dose of the patient The correct answer is D. Decrease the radiation dose of the patient. Intensifying films MUST be used with extraoral radiographic films in order to decrease the dose of radiation to the patient. Radiation is harmful, even in small doses, toi ndividual cells in the body. Radiation can cause abnormal changes that leads to cancer. Intensifying screens when used with x ray films using emulsions, make them more sensitive to blue or green light. The X-ray photons are converted to visible light photons when they strike the screen. Lead aprons and thyroid collars are mandatory preventive armamentarium in dental radiograhy.