General

Question 1

How does LA work?

Answer 1

Blocks voltage gated sodium channels and prevents up regulation of action potentials

Question 2

What is in a cartridge of LA?

Answer 2

Base hydrochloride
Vasoconstrictor
Fungicide
Reducing agent: sodium metabisulfide
Preservative: methylparaban

Question 3

An amalgam has an overhang on its mesial surface. How could this have been avoided?

Answer 3

Correct adaptation of matrix
Wedge
Adequate condensing of amalgam

Question 4

Name 4 types of articulator.

Answer 4

Simple hinge
Average value
Semi-adjustable
Fully adjustable

Question 5

Give 4 functions of a facebow.

Answer 5

Transfers the relationship between the maxillary teeth and the axis of rotation from the patient to the articulator
Positions the upper cast vertically
Transfers the angulation of the maxillary occlusal plane in relation to a horizontal reference plane
Used for mounting upper cast only

Question 6

What are the principles of crown preparation?

Answer 6

Preserve tooth structure
Retention and resistance
Structural durability
Marginal integrity
Preserve periodontium
Aesthetics

Question 7

What are the stages of crown preparation?

Answer 7

Occlusal reduction
Separation
Buccal reduction
Palatal/lingual reduction
Finishing

Question 8

What is Posselts Envelope?

Answer 8

Extremes of mandibular movement
Border movements of the mandible in the sagittal plane

Question 9

What are the principles of cavity design and preparation?

Answer 9

Identify and remove carious enamel
Remove enamel to identify the maximal extent of the lesion at the amelodentinal junction and smooth the enamel margins
Progressively remove peripheral caries in dentine- from the ADJ first then circumferentially deeper
Outline form modification, enamel finishing, occlusion, requirement of restorative materials
Internal design modifications, internal line and point angles (make cavity smooth

Question 10

What determines cavity design?

Answer 10

Structure and properties of the dental tissues
The diseases (dental caries, periodontal disease, tooth surface loss)
Properties of restorative materials
History

Question 11

When should dental caries be intervened?

Answer 11

When the lesion is cavitated
When the patient can’t access the lesion for prevention
The lesion is into dentine radiographically
The lesion is causing pulpal damage

Question 12

What does fluoride do?

Answer 12

Incorporation into enamel crystal to form fluorapatite which is more caries resistant than hydroxyapatite
Interferes with the adhesion force of bacteria reducing their ability to stick to the surface of the teeth