MDS PREP
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.
High heat obturation technique refers to
1) Thermofill technique
2) Ultrafill technique
3) Sectional filling
4) Obtura II technique
Endodontics
Answer: 4
Obtura II is a high heat obturation technique used in endodontics (root canal treatment) to fill and seal the root canal system of teeth. This technique involves the use of a thermoplasticized gutta-percha, which is heated to a high temperature and then compacted into the root canal with a heat source such as a heated plugger or a heated tip of a handpiece. The heat helps to soften the gutta-percha, allowing it to adapt to the irregularities of the root canal system and form a tight seal against bacterial microleakage. Thermofill and Ultrafill are not high heat techniques, while sectional filling is a method of filling the canal in increments, which may or may not involve heat.
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.
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.
Operator can identify root curvatures ledgings an additional curvatures by
1. Perception by instrumentation
2. Radiographic examination
3. By his knowledge of tooth anatomy
4. None of the above
Endodontics
Answer: 1
Identifying Root Curvatures
Perception by instrumentation refers to the tactile
feedback that a dentist can obtain while using instruments during
procedures, allowing them to identify curvatures in the root canal system.
In hot bead sterilizer, temperature is highest in
1. Inner zone of the sterilizer
2. Outer zone of the sterilizer
3. Equal in both outer and inner zone
4. Variable
Endodontics
Answer: 2
In a hot bead sterilizer, the temperature is highest in the inner zone of the sterilizer. A hot bead sterilizer uses a heated metal bead to transfer heat to the instruments, which are placed around the bead in a basket. The inner zone is where the bead is located and where the temperature can reach up to 300°C, which is sufficient to kill microorganisms and sterilize the instruments. The outer zone is cooler and does not contribute significantly to the sterilization process.
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.