MDS PREP
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.
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.
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.
Pulp exposures of crowns come under which class according to WHO nomenclature
1. 873.60
2. 873.61
3. 873.62
4. 873.63
Endodontics
Answer: 3
Explanation: According to the WHO classification of dental injuries, pulp exposures due to crown fractures are classified under 873.62. This classification helps in standardizing the terminology used in dental trauma, allowing for better communication and understanding among dental professionals.873.60 - Pulp Exposure due to TraumaThis code refers to cases where the pulp is exposed as a result of trauma to the tooth. It does not specify whether the pulp is vital or non-vital, but it indicates that there is a direct exposure of the pulp tissue.873.61 - Avulsion of ToothThis code is used for cases where a tooth has been completely displaced from its socket (avulsed). In avulsion cases, the pulp is typically exposed, and immediate re-implantation is critical for the best prognosis. This classification highlights the severity of the injury and the need for urgent treatment.873.62 - Crown Fracture with Pulp InvolvementThis code refers to fractures of the crown of the tooth that involve the pulp. It indicates that the fracture has extended into the pulp chamber, necessitating treatment such as root canal therapy.873.63 - Crown Fracture without Pulp InvolvementThis code is used for crown fractures that do not involve the pulp. In these cases, the injury is limited to the enamel and dentin, and the pulp remains intact.
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 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.
Most frequent failures of root canal treated cases are due to
1. Inadequate obturation
2. Improper sterilization
3. Improper preparation
4. All of the above
Endodontics
Answer: 1
The most frequent failures of root canal treated cases are often due to
inadequate obturation. This can occur when the root canal filling material does
not completely fill the space or when it is not properly compacted, leaving gaps
where bacteria can persist and cause reinfection. Proper preparation and
sterilization are also crucial, but inadequate obturation is the most common
technical error leading to treatment failure.
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.