MDS PREP
The most common age group of fractures of permanent teeth
1. 8-12 years
2. 4-5 years
3. 1-2 years
4. 3-6 years
Endodontics
Answer: 1
Explanation: The age group of 8-12 years is commonly associated with the highest
incidence of dental fractures in permanent teeth. This is often due to increased
physical activity and sports participation during this developmental stage,
leading to a higher risk of trauma.
While combining NaOCH and H2O2 as irrigants
1) H2O2 should be used last
2) NaOCH should be used last
3) First irrigation should be done by normal saline
4) NaOCH and H2O2 should never be used simultaneously
Endodontics Answer: 2
Because residual H2O2 might react with debris and produce gas that can cause continuous pain.
The X-ray of a traumatized tooth is important because
1. To determine root fracture
2. To assess the stage of root development
3. As basis for future treatment
4. All the above
Endodontics
Answer: 4
Explanation: X-rays are essential in evaluating traumatized teeth for multiple
reasons, including detecting root fractures, assessing root development, and
planning future treatment. This comprehensive view aids in effective management
of dental trauma.
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.
Gutta-percha cones should not be used for root canal filling in
1. Primary teeth
2. Permanent mandibular last molars
3. Teeth with wide root canal
4. Teeth with curved roots
Endodontics
Answer: 1
Gutta-percha cones are generally not recommended for root canal filling in
primary teeth because the root canals of primary teeth are more likely to
contain vital tissue, and the material can potentially cause harm to these
tissues. However, they are suitable for permanent teeth with wide root canals
and even those with curved roots, provided that the root canals are properly
cleaned and shaped to allow for optimal filling.
The principal cone of gutta-percha used for condensation should
1. Fit exactly at apex
2. Have a definite apical seal
3. Fit loosely in the canal
4. Be 2 mm from the apex
Endodontics
Answer: 2
In endodontics, the primary goal of using gutta-percha is to achieve a proper seal at the apex of the root canal system. A definite apical seal is crucial to prevent the ingress of bacteria and fluids, which can lead to reinfection. While the cone should fit well within the canal, the emphasis is on achieving a good seal rather than merely fitting exactly at the apex or being 2 mm from it.
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.
According to WHO nomenclature of pulp injuries, "avulsion" is classified of pulp injuries as
1. 873.60
2. 873.61
3. 873.68
4. 873.69
Endodontics
Answer: 2
Explanation: In the WHO classification, avulsion refers to the complete
displacement of a tooth from its socket, and it is classified under 873.61. This
classification is crucial for understanding the severity of the injury and
determining the appropriate treatment.