MCQs

Question 1

. In which situation would it not be suitable to provide a patient with a complete
overdenture?
a. When it is proposed to increase the face height
b. Root canal therapy is contraindicated due to systemic disease or root canal shape
c. Retention is expected to be poor
d. There has been significant alveolar atrophy at sites of previous extraction

Answer 1

B

Question 2

Which of the following is a contraindication for immediate dentures?

a. Remaining teeth are a health risk
b. Fewer visits are essential
c. Easy extractions
d. Large bony undercuts

Answer 2

D

Question 3

A 42 year old male comes in and complains that his upper complete denture “Comes down at the back when I bite” if the denture itself is adequately extended, what is the likely reason for the lack of seal?

Answer 3

Denture base polymerisation shrinkage of polymer/ monomer dough

Question 4

At what interval of time is an immediate complete denture replaced by its permanent
counterpart?

Answer 4

12 months

Question 5

The conventional ‘labial flange’ used for complete immediate dentures is for

Answer 5

Supporting maxillary ridge and giving an improved seal

Question 6

Which of the following is NOT an elastomeric impression material?

a. Polyethers
b. Addition silicones
c. Zinc oxide eugenol
d. Polysulphides

Answer 6

Zinc oxide eugenol

Question 7

Balanced articulation can be defined as:

Answer 7

An arrangement of the artificial teeth whereby the dentures provide mutual stability in all successive lateral and protrusive excursions by means of bilateral interocclusal contact.

Question 8

Which bins for which substances

Answer 8

Orange: non-sharp contaminated waste
Yellow: clinical or animal waste
Black: household waste
Sharps: needles, disposable syringes, scalpel blades, burs, matrix bands, rosehead, glass
Autoclave: kits, gallipots, clamps and frames, hand pieces, burs

Question 9

Amalgam waste

Answer 9

Large bins for amalgam capsules
Small pots for excess amalgam
Square sinks with filters for contaminated water
Mercury spillage: report immediately to clinical supervisor and use cleaning kit (red plastic box)
-stop work and switch off amalgamator
-confine spill to a minimum and avoid mercury on floor
-increase ventilation, put on protective gloves and mask
-move globules together to form one pool using scoop provided
-pick up as much with syringe and place in waste container
-return empty syringe to spillage kit
-mix equal amounts of sulphur and calcium hydroxide using plastic pot and spatula and spread onto spillage using brush for 2-3mins (or alloy wool - leave flattened area on top of loose mercury for 20s)
-brush powder or paste into scoop and transfer to waste container, then cap tightly
-replace in spillage kit in well ventilated place away from sources of heat

Question 10

Setting up a cavitron

Answer 10

1. Fill cavitron with distilled water from bottle - NO GLOVES, clean hards
2. Open up non-surgical kit with clean gloves
3. Connect black handpiece to wire from cavitron and turn dial to full power
4. Over sink press footpedal on floor and make sure water is coming through
5. Get handpiece tips from non-surgical kit and attach to black handpiece
6. Adjust water until fine mist is evident
7. Turn dial so it is halfway to midpoint, ready for patient

Question 11

Maximum amount of lignocaine to administer to a 50kg patient

Answer 11

4.4mg/ kg in healthy patient of 2% lignocaine

So 50 x 4.4 x 0.02 = 11ml

Question 12

Maximum doses of articaine and lignocaine

Answer 12

Lignocaine: 4.4mg/ kg
Articaine:
-adult 7mg/ kg
-child 5mg/ kg

Question 13

Working out max dose of LA to give a child

Answer 13

Body weight = (age + 4) x 2

Weight x concentration x max number ml/ kg

Question 14

What is Reye’s syndrome and what is it caused by?

Answer 14

Rare
Can cause serious liver and brain damage
Affects patients <20yrs
Symptoms usually begin after viral infection treated with aspirin

Question 15

How does penicillin act?

Answer 15

Beta-lactams act against cell wall of bacteria

• inhibit normal cell wall formation by inhibiting PBPs
• mimics structure of D-ala-D-ala

Question 16

What to use to extract a lower molar tooth

Answer 16

Lower molars 
-figure of 8 and buccal movement
-73 or 75
-cowhorns force beak underneeth teeth and lift them out of socket (use for initial movement)
Upper molars 
-76H
-buccal movement
Beak to cheek

Question 17

Prevalency of incompetent lips

Answer 17

Up to 80% at some time in childhood

-may gradually become competent due to differential growth rates of skeletal and sot tissue elements

Question 18

Distance between incisive papilla and central incisor

Answer 18

Average 11.8mm

Question 19

Types of haemorrhage

Answer 19

Primary: as soon as tooth is removed (due to bleeding disorder or local cause)
Reactionary: within 48hrs (due to alcohol, exercise, heat, anaesthetic wearing off)
Secondary: approx 1 week later (due to infection)

Question 20

Risk of death from GA

Answer 20

1:250,000