MDS PREP
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 length of the instrument used for endodontic implants is
1) 25 mm
2) 28 mm
3) 21 mm
4) 40 mm
Endodontics
Answer: 4
Endodontic instruments, particularly those used for root canal treatment and
implants, typically have a length of around 40 mm. This length allows for
adequate reach into the root canals of most teeth, which can vary in depth.
Instruments shorter than this may not effectively reach the apical areas of the
root canals.
The filling of choice for primary root canals
1. ZOE
2. Calcium hydroxide
3. Gutta-percha
4. Chlorpercha
Endodontics
Answer: 1
Zinc oxide eugenol is commonly used as a filling material for primary root canals due to its biocompatibility and sealing properties.
Endodontically treated posterior teeth are more susceptible to fracture that untreated posterior teeth. The best explanation for this is
1. Moisture loss
2. Loss of root vitality
3. Plastic deformation of dentin
4. Destruction of the coronal architecture
Endodontics
Answer: 4
Loss of Coronal Structure: During endodontic treatment, the
coronal portion of the tooth may be significantly altered or reduced, especially
if there is extensive decay or if a crown is required after treatment. The loss
of tooth structure compromises the tooth's ability to withstand occlusal forces.
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.
Smallest No. file is
1) 4
2) 6
3) 8
4) 10
Endodontics
Answer: 2
In endodontics, files are numbered according to their size, with smaller numbers indicating larger files. The smallest file commonly used is size 6.