MDS PREP
The mechanical advantage obtained from the wheel and axle principle of elevator is
1. 2.5
2. 3
3. 4.6
4. 6
Oral Surgery
Answer: 3
The mechanical advantage obtained from the wheel and axle principle of elevator is 3.
Eburnation is seen in
1) Malunion
2) Nonunion
3) Osteomyelitis
4) Osteoradionecrosis
Oral Surgery
Answer: 2
Eburnation is the process of converting living bone tissue into a sclerotic, or hardened, avascular bone due to lack of blood supply. This can occur at the site of a nonunion, which is where a fracture fails to heal properly, and the bone ends remain separate.
Rapid onset of action seen by local anaesthesia in small nerve endings is due to
1. Increased threshold of small nerves due to depolarization
2. Low pH of small nerve fibres
3. High ratio of surface area to the volume of small nerve fibres
4. None of the above
Oral Surgery
Answer: 3
Rapid onset of action seen by local anaesthesia in small nerve endings is due to the high ratio of surface area to the volume of small nerve fibres.
To drain pus from an abscess, the surgeon should
1) Cut an eclipse from the abscess surface to allow for a drain
2) Aspirate the contents
3) Penetrate into abscess cavity & probe with an artery forceps to allow for flow of pus
4) Cut only the mucosa and skin
Oral Surgery
Answer: 3
��Proper abscess drainage involves creating an incision to allow pus to drain completely. Probing with an artery forceps ensures complete evacuation of the cavity. Other methods, like simple aspiration or superficial incisions, may not adequately drain the abscess.
To perform tracheostomy entry should be made at the
1) Cricothyroid ligament
2) Thyroid membrane
3) Thyroid notch
4) Cricoid cartilage
Oral Surgery
Answer: 1
A tracheostomy is a surgical procedure that involves creating an opening in
the trachea (windpipe) to facilitate breathing. The preferred site for making
the incision during a tracheostomy is the cricothyroid ligament,
which is located between the cricoid and thyroid cartilages.
Cricothyroid ligament: This ligament is relatively
superficial and provides a safe access point to the airway, especially in
emergency situations. It is often chosen for emergency tracheostomy because
it is easier to locate and access quickly.
Most commonly used local anaesthesia
1. 1: 20,000 xylocaine HCL
2. 1: 50,000 xylocaine HCL
3. 1: 10,000 xylocaine HCL
4. 1: 80,000 xylocaine HCL
Oral Surgery
Answer: 4
Most commonly used local anaesthesia is 1: 80,000 xylocaine HCL.
For extraoral maxillary nerve block the target is�
�1. Anterior to lateral pterygoid plate
�2. Posterior to lateral pterygoid plate
�3. Pterygomandibular fossa
�4. Pterygomandibular fissure
Oral Surgery
Answer: 1
Anterior to lateral pterygoid plate. In the extraoral maxillary nerve block, the
needle is inserted at the posterior aspect of the condylar neck and directed
anteriorly to target the pterygomandibular space, which contains the maxillary
nerve and its branches. This technique is used to anesthetize the molars and
premolars of the upper jaw and is also known as the Vazirani-Akinosi technique.
A patient is on periodic renal dialysis. Minor oral surgery should be performed �
�1. One day before dialysis
�2. On the day of dialysis
�3. One day after dialysis
�4. One week after dialysis
Oral Surgery
Answer: 3
Minor oral surgery should be performed one day after dialysis in a patient who
is on periodic renal dialysis. This is because the patient's platelet count and
coagulation factors are usually at their lowest before dialysis, which could
increase the risk of bleeding.