Restorative Dentistry

Question 1

two types of amalgam particles?

Answer 1

spherical

lathe cut

Question 2

what reacts with mercury when amalgam is mixed?

Answer 2

Ag3Sn

Question 3

what is the gamma phase associated with?

Answer 3

corrosion, creep and lower strength

Question 4

modern amalgams have a lower gamma phase because increased concentration of what?

Answer 4

copper

Question 5

why can amalgam withstand forces?

Answer 5

good compressive strength

Question 6

how is corrosion reduced?

Answer 6

increased copper

Question 7

what can corrosion products be beneficial for?

Answer 7

better marginal seal and reduce microleakages

Question 8

amalgam does not bond chemically so what is necessary?

Answer 8

retention and resistance form to retain the material in the cavity

Question 9

what restorations are indicated to be amalgam filled?

Answer 9

posteriors
large occlusal forces
where resin not suitable

Question 10

what does the setting reaction of a resin involve?

Answer 10

polymerisation of the matrix

Question 11

what is the setting reaction initiated by?

Answer 11

free raducals - intitiate polymerisation

Question 12

what do light cured materials contain?

Answer 12

camphorquinone

Question 13

what is added to resins to reduce shrinkage?

Answer 13

methacrylate monomers such as BISGMA

Question 14

the more filler the more?

Answer 14

stonger and harder wearing the resin is

Question 15

in composites what is added to ensure the resin and filler work together?

Answer 15

a coupling agent

Question 16

what is the difference between flowable and traditional composites?

Answer 16

less filler content by 50-70% = less viscous

low wear resistance

Question 17

indications for composites?

Answer 17

occlusals on posterior teeth
proximal lesions
cervical lesions
incisal edge lesions
fissure sealants/PRR

Question 18

contraindications for composites?

Answer 18

areas of large occlusal loading
tooth cant be isolated
root surface lesions - GI is better option
deep interproximal boxes

Question 19

what are the essential components of GI?

Answer 19

polyalkenoate acids and ion leachable glass

Question 20

what are the advantages of RMGICs?

Answer 20

self adhesion to tooth
command cure set
fluordie releasing

Question 21

disadvantages of RMGICs?

Answer 21

poor fracture strength
water absorption
poor strength in thin sections
stain build up is common

Question 22

glass ionomer cement indications of use?

Answer 22

liners and bases
ART
root surface caries