MDS PREP
The addition of hyaluronidase to a local anaesthetic solution might
1) Increase the duration of anaesthesia
2) Limit the area of anaesthesia
3) Reduce bleeding
4) Enhance diffusion of local anaesthetic
Oral Surgery
Answer: 4
Hyaluronidase is an enzyme that breaks down hyaluronic acid, a component found in the extracellular matrix. When added to a local anesthetic, it increases the permeability of tissues, facilitating enhanced diffusion of the anesthetic agent into the surrounding areas. This can broaden the spread of the anesthetic, allowing for a more effective and comprehensive blockade of nerve signaling.
If efforts in cardiopulmonary resuscitation are effective there will be
1) Constriction of pupils
2) Dilatation of pupils
3) Hypertension immediate
4) None of the above
Oral Surgery
Answer: 1
Effective cardiopulmonary resuscitation (CPR) can lead to improved cerebral
perfusion and oxygenation, which may result in constriction of the pupils (miosis)
as the body begins to recover from the state of shock.
Of the following which tooth is most difficult to anaesthetize by infiltration technique alone
1. Maxillary canine
2. Macillary central incisors
3. Maxillary first molar
4. Maxillary first premolar
Oral Surgery
Answer: 3
Of the following, the maxillary first molar is the most difficult to anaesthetize by infiltration technique alone.
For a 8-year-old child with TMJ ankylosis, the treatment of choice is
1. Gap arthroplasty
2. Condylectomy
3. Gap arthroplasty with costochondral grafting
4. Treatment not required
Oral Surgery
Answer: 3
For an 8-year-old child with TMJ ankylosis, the treatment of choice is gap arthroplasty with costochondral grafting.
The following anatomical landmarks are useful in the closed mouth approach of mandubular nerve block except
1. Occlusal plane of occluding teeth
2. Anterior border of ramus
3. Mucogingival junction of the mandibular teeth
4. A & B
Oral Surgery
Answer: 3
The closed mouth approach of mandibular nerve block relies on the anatomical
landmarks of the occlusal plane of occluding teeth and the anterior border of
the ramus. The mucogingival junction is not a relevant landmark for this
technique.
Which is the best method to counteract severe acidosis following cardiopulmonary resuscitation?
1) Administration of adrenaline by IV routes
2) Administration of sodium bicorbonate intravenously
3) Administration of adrenaline intramuscularly
4) No treatment is necessary because it is self-limiting
Oral Surgery
Answer: 2
Severe acidosis, particularly metabolic acidosis, can occur following
prolonged cardiac arrest and subsequent CPR. The primary goal in managing such
cases is to restore normal pH levels in the body, which is crucial for proper
cellular function and overall physiological homeostasis.
1. Sodium bicarbonate Sodium bicarbonate is a strong base that reacts with
hydrogen ions (H+), which are responsible for acidity in the blood, to form
carbon dioxide (CO2) and water (H2O). This reaction helps to neutralize the
excess hydrogen ions, thereby raising the pH of the blood. It is administered
intravenously because it allows for rapid distribution throughout the body and
direct access to the circulatory system where it can counteract acidosis most
effectively. The intravenous route ensures that the medication reaches the
bloodstream quickly and in a controlled manner, making it the preferred method
for acute and severe cases.
2. Adrenaline (epinephrine)*: Although adrenaline is a crucial medication used
in CPR for its vasopressor and cardiac stimulant effects, it is not the primary
treatment for severe acidosis. Adrenaline is typically administered to improve
cardiac output and blood pressure during CPR.
Patients with end-stage renal disease are of increased risk when undergoing extraction of teeth because they
1. Have an increased tendency to bleed
2. Are susceptible to infections
3. Are often on steroid therapy
4. All of the above
Oral Surgery
Answer: 4
Patients with end-stage renal disease are at increased risk during tooth
extraction due to several factors. They often have an increased tendency to
bleed due to platelet dysfunction and are susceptible to infections due to
compromised immunity. Additionally, they are often on steroid therapy, which can
affect wound healing and increase the risk of infection.
Local anaesthetic cartridges contain small bubbles. These bubbles contain
1. Oxygen gas
2. Carbon dioxide gas
3. Nitrogen gas
4. Carbon monoxide gas
Oral Surgery
Answer: 3
Local anaesthetic cartridges contain small bubbles of nitrogen gas.