2014 #4 Use of composite restoration materials

Question 1

Name the sequences outlined by Black for Tooth cavity preparation

Answer 1

Resistance
Retention
Convenience
Pathology Removal
Wall preparation
Preparation cleansing forms

Question 2

in which classes of cavity preparation is beveling of the occlusal cavosurfaces contraindicated because it enlarges the surface area of the restorative in occlusion?

Answer 2

Class I or II

Question 3

in which classes of cavity preparation is beveling of the occlusal cavosurfaces advised because provides greater retention strength due to greater enamel surface area and improves esthetics?

Answer 3

Class III - VI

Question 4

what do acid etchants do?

Answer 4

Dentin is demineralised, exposing the connective tissue for bonding
Collagen fibres within the dentinal tubules are opened exposing more micropores for infiltration by the resin
Removes the smear layer

Question 5

what do applied bonding agents do?

Answer 5

Improve retention of the restorative
Prevent leakage at the margins
Decrease discolouration and pulp sensitivity

Question 6

How deep do bonding agents penetrate to?

Answer 6

200 - 400 microns

Question 7

for a light curing resin what strength of visible light is required to set it?

Answer 7

460 - 480nm