MDS PREP
Which of the following statements about developing a dental radiograph is false?
1) It involves chemically precipitating metallic silver
2) It it is too long, it results in an over dark radiograph
3) It typically involves a developer containing sodium thiosulphate
4) None of the above
Radiology
Answer: 2
Explanation: This statement is false because if the developing time is too long, it typically results in an overexposed radiograph, which appears too dark. However, if the developing time is too short, it can lead to an underexposed radiograph, which appears too light.
The anatomical structure of mandible commonly seen in periapical films of maxillary third molar region is
1) Coronoid process
2) Condylar process
3) Ramus mandible
4) Body of mandible
Radiology
Answer: 1
The coronoid process of the mandible may project into the maxillary third molar region on periapical radiographs when the patient opens their mouth wide. Other structures, like the condylar process or ramus, are less likely to overlap in this region.
Which of the following is true of paralleling cone technique
1. The radiopacity of the zygoma is superimposed on the roots of third molars
2. Easy to place with the film holder
3. Less of gag reflex
4. No need to sterilize the firm holder
Radiology
Answer: 2
Which of the following is true of the paralleling cone technique: it is easy to place with the film holder.
The extraoral radiograph that best demonstrates the subcondylar portion of mandible is the (neck of the condyle)
1. AP mandible
2. Waters view
3. Towne"s view
4. Submental vertex
Radiology
Answer: 3
The extraoral radiograph that best demonstrates the subcondylar portion of the mandible is Towne's view.
Radiographic image of a malignant tumour is
1. Distinct sclerotic borders
2. Geographic bone destruction
3. Sunburst appearance
4. All of the above
Radiology
Answer: 3
Radiographic image of a malignant tumour is characterized by sunburst appearance.
Double intensifying screen and screen film are used in extraoral radiographs to
1. Reduce density
2. Reduce contrast
3. Reduce exposure time
4. Reduce secondary radiation
Radiology
Answer: 3
Double intensifying screen and screen film are used in extraoral radiographs to reduce exposure time.
Reflecting layer used in intensifying screens
1. Calcium tungstate
2. Titanium oxide & magnesium carbonate
3. Gaddinium oxysulphide
4. Lanthanum oxybromide
Radiology
Answer: 2
The reflecting layer used in intensifying screens is titanium oxide & magnesium carbonate.
Which of the following has a radiolucency closest to the dentin
1. ZOE
2. Calcium hydroxide
3. Silicophosphate
4. Gutta percha
Radiology
Answer: 3
Which of the following has a radiolucency closest to the dentin: silicophosphate.