MDS PREP
The primary airway hazard for an unconscious patient in a supine position is
1) Tongue obstruction
2) Bronchospasm
3) Laryngospasm
4) Aspiration
Oral Surgery
Answer: 1
In an unconscious patient lying supine, the tongue can fall back and obstruct
the airway due to loss of muscle tone. This is the most common airway hazard in
this position.
Which of the following local anaesthetics is a vasoconstrictor
1. Lidocaine
2. Procaine
3. Bupivacaine
4. Ropivacaine
Oral Surgery
Answer: 4
Ropivacaine is a vasoconstrictor.
One decided to use forceps for removal of a tooth. The first direction for the force to be applied is
1. Buccally
2. Lingually or palatally
3. Apically
4. Occlusally
Oral Surgery
Answer: 3
When using forceps for removal of a tooth, the first direction for the force to be applied is apically.
Which of the following procedures is best suited to correct bimaxillary protrusion
1. Extraction of four premolars and anterior alveolar segment repositioning
2. Mandibular body osteotomy and posterior maxillary osteotomy
3. Subcondylar osteotomy
4. None of the above
Oral Surgery
Answer: 1
The best procedure to correct bimaxillary protrusion is extraction of four premolars and anterior alveolar segment repositioning. Bimaxillary protrusion is a condition where both the upper and lower jaws are positioned too far forward. This can be corrected by extracting the four premolars (two from the upper and two from the lower jaw) to create space for the teeth to move backward and then repositioning the anterior alveolar segments (the bone and gum tissue holding the front teeth) to achieve a more favorable facial profile and occlusion. This approach addresses the protrusion of both jaws simultaneously and is more effective than the other options listed, which are more targeted at specific jaw issues (mandibular body osteotomy and subcondylar osteotomy) and not as comprehensive for bimaxillary protrusion cases.
All of the following statements of nasal fractures are true except
1) Even if minor, they may be followed by bilateral ecchymosis and facial oedema
2) They may need to be reduced for a few weeks
3) They need not be complicated by traumatic telecanthus
4) They may lead to the telescoping of the nasal complex into the frontal sinus
Oral Surgery
Answer: 2
Nasal fractures, even minor ones, can lead to bruising (ecchymosis) and
swelling (edema) around the nose and face due to the vascularity of the area.
Most nasal fractures, especially minor ones, do not require reduction
(surgical realignment) unless there is significant displacement or functional
impairment. Typically, if reduction is necessary, it is done shortly after the
injury, not for a few weeks.
Traumatic telecanthus (increased distance between the inner canthi of the
eyes) can occur with severe nasal injuries, but it is not a necessary
complication of all nasal fractures.
Severe nasal fractures can lead to complications such as the telescoping of
the nasal complex, which may involve displacement into adjacent structures,
including the frontal sinus.
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
The addition of hyaluronidase to a local anaesthetic solution might enhance diffusion of local anaesthetic.
One wants to anaesthetise the inferior alveolar nerve at the point at which it exits from the mandibular canal, so the injection site most often located in
1. Between first and second molars inferior to the root apices
2. Between first and second molar superior to root apices
3. Between first and second premolars inferior to root apices
4. Between first and second premolars superior to root apices
Oral Surgery
Answer: 3
The inferior alveolar nerve exits the mandibular foramen and runs in the
mandibular canal before it branches off to supply the teeth, including the
second premolar. To anesthetize the nerve at this point, the injection site is
commonly located between the first and second premolars, inferior to the root
apices, where the nerve is relatively superficial and accessible.
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.