MDS PREP
Which of the following fractures of tooth was poorest prognosis
1) Horizontal fractures at gingival level
2) Vertical root fractures
3) Horizontal fractures at apical third of root
4) Horizontal fractures at middle third or root
Endodontics
Answer: 2
Vertical root fractures are often associated with a poor prognosis because they can lead to significant loss of tooth structure and are difficult to treat. They typically result in the need for extraction, especially if they extend into the periodontal ligament or if the fracture is not detected early.
Enamel fracture without tooth structure loss or incomplete enamel fracture results from
1. Concussion
2. Avulsion
3. Subluxation
4. None of the above
Endodontics
Answer: 1
Explanation: A concussion in dental trauma refers to a situation where the tooth
is not displaced but may have sustained an injury that can lead to an enamel
fracture. This type of injury does not involve loss of tooth structure, which
aligns with the description of an enamel fracture without tooth structure loss.
Enlargement of the calcified canals is done with
1. EDTA
2. Calcium hydroxide
3. Sodium hypochlorite
4. Sodium chloride
Endodontics
Answer: 1
EDTA (ethylenediaminetetraacetic acid) is a chelating agent commonly used in endodontics to remove the smear layer and facilitate the enlargement of calcified canals. It helps in dissolving inorganic components of the dentin, making it easier to access and clean the root canal system.
The irrigating should used with ultrasonic instruments used for preparation of root canal is
1) Sodium hypochlorite
2) Normal saline
3) Hydrogen peroxide
4) Chloramine
Endodontics
Answer: 1
Sodium hypochlorite is commonly used as an irrigating solution with ultrasonic instruments in endodontic treatment for its antimicrobial properties. It helps in the cleaning and disinfection of the root canal system by removing organic debris and bacteria. Normal saline, hydrogen peroxide, and chloramine are also used as irrigants, but sodium hypochlorite is the most effective in eliminating bacteria.
The disadvantage of glass bead sterilizer
1) Only small instruments can be sterilized
2) Variable temperature
3) Does not produce effective heat for sterilization
4) All of the above
Endodontics
Answer: 1
Explanation:
One of the main disadvantages of glass bead sterilizers is that they are limited to sterilizing only small instruments due to the size of the sterilization chamber. Larger instruments cannot be effectively sterilized in this type of device.
The success of a root canal filling is best assessed
1. Clinical observation
2. Size of gutta-percha cone used
3. Radiographs
4. By the diameter of root canal reamer
Endodontics Answer: 1
The success of a root canal filling is primarily assessed through clinical
observation, which includes monitoring for signs of pain, swelling, and
infection. While radiographs and the size of the gutta-percha cone used can
provide additional information, the ultimate determinant of success is the
patient's symptom resolution and the absence of pathology.
D2 on the endodontic file indicates
1) Diameter at tip of instrument
2) Angle of instrument
3) Length of instrument
4) 1/100th mm at end of cutting blade
Endodontics
Answer: 4
The designation "D2" on an endodontic file indicates the diameter of the file at
the tip, measured in hundredths of a millimeter. This helps clinicians select
the appropriate file size for root canal treatment.
When pulp cannot be extirpated in narrow canals, which of the following can be used
1. Obtundant
2. Astringent
3. Haemostatic
4. Mummifying agent
Endodontics
Answer: 4
Explanation: A mummifying agent, such as paraformaldehyde,
is used to preserve the pulp in cases where extirpation is challenging. This
approach is often used as part of pulp therapy in certain endodontic treatments.