MDS PREP
The region which is closest to satisfying all the principles of shadow casting and parallel placement of the film in a paralleling technique full mouth series of periodical radiographs is
1) Maxillary premolar view
2) Mandibular premolar view
3) Maxillary molar view
4) Mandubular molar view
Radiology
Answer: 4
Disadvantages of using a GRID during radiography is
1) Increased patient exposure
2) Decreased exposure time
3) Increased secondary radiation fog to film
4) Reduces secondary radiation to film
Radiology
Answer: 1
Mean exposure at skin from an intraoral periapical radiographs
1) 300 mR
2) 0.03 mR
3) 47 mR
4) Both A and B
Radiology
Answer: 4
Half value layer refers to
1) The rate at which an X-ray photon transfer"s the energy to irradiated matter
2) The thickness of a substance required to reduce the number of X-ray photons by half
3) Both the above
4) None of the above
Radiology
Answer: 2
If the size of object is 20 cm, object-film distance is 5 cm and source-film distance is 25 cm, what is the size of object on film
1. 20 cm only
2. 21 cm only
3. 25 cm only
4. 22 cm only
Radiology
Answer: 3
Overlapping of proximal structures in a periodical or bitewing radiograph is due to
1) Incorrect horizontal positioning of cone
2) Incorrect vertical positioning of cone
3) Incorrect vertical positioning
4) None of the above
Radiology
Answer: 1
X-rays were discovered in
1. Nov 1897
2. Oct 1985
3. Nov 1895
4. Nov 1890