MDS PREP
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.
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.
Activity of disinfectants is
1) Reduced by organic debris or blood
2) Increased with heat
3) Hastened by adding 5 % oxygen
4) Nullified by ethylene dioxide gas
Endodontics
Answer: 1
Activity of disinfectants is indeed reduced by organic debris or blood. This is because organic materials can act as a barrier, protecting microorganisms from the disinfectant and reducing its effectiveness. The presence of organic matter can bind to the disinfectant, inactivate it, or consume it, thereby reducing its ability to kill or inhibit the growth of microorganisms. For this reason, it is essential to thoroughly clean and debride the area before applying a disinfectant to ensure optimal efficacy.
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.
In class III Ellis fracture
1. Only enamel is involved
2. Enamel and dentin are involved
3. Enamel,dentin and pulp are involved
4. Non-vital pulp
Endodontics
Answer: 3
Class III: Enamel-Dentin-Pulp Fracture
Description: Involves enamel, dentin, and exposes
the pulp.
Endodontic Consideration: This type of fracture
typically requires endodontic treatment (root canal therapy) to manage
the exposed pulp and prevent infection. The prognosis depends on the
extent of the fracture and the vitality of the pulp.
There is a real relationship between the incidence of fractured anterior teeth and the
1) Caries in those teeth
2) Hardness of the enamel
3) Hardness of the dentin
4) Protrusion of those teeth
Endodontics
Answer: 4
The protrusion of anterior teeth can increase the risk of fractures due to their position and exposure to occlusal forces. Protruded teeth are more susceptible to trauma and stress during biting and chewing, which can lead to fractures. Additionally, protruded teeth may not have adequate support from adjacent teeth, further increasing their vulnerability to fracture.
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 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.