First part/ Give reasons
1- Metal have high thermal conductivity.
2- For calculation of deformation in 3 point loading test , the
length and thickness are the most important parameters.
3- Tooth structure poses obstacles to proper adhesion.
4- The addition of small amount of inhibitor to monomer is
essential.
5- Molecular solids are weaker than atomic solids.
6- Etchant is done to enamel surface before application of
composite filling.
7- Brittle material have high compressive strength and low
tensile strength.
8- Refractive index of the tooth and restorative material
should be match.
9- Adhesive liquid should have low surface tension.
10- Ability of pure gold to be easily shaped into sheets and
wires.
11- Thermal diffusivity is more important than thermal
conductivity.
12- ductile material have low compressive strength and high
tensile strength.
13- Surface irregularity is a double edged weapon factor
effecting wetting.
14- Co-polymer enables us to tailor make polymers.
15- Secondary bond are weak bond.
16- Low softing temperature of polymers.
17- Wax are not easily wetted.
18- Denture lining materials are flexible and resilient in
patient mouth.
19- Thick adhesive film should be avoided.
20- Non-metallic denture base is advantage an disadvantage.
21- Thermoset polymer are stronger than thermoplastic
polymers.
22- Using a primer after etching the dentine surface.
23- Addition polymerization reaction gives rise to polymer
with better dimensional than condensation polymerization
polymer.
24- The higher strength properties of a quenched metal than
which was slowly cooled.
25- A cold worker material structure is stronger and harder
than a cast metal structure.
26- Cross linking increase glass transition of polymer.
27- Prolonged heating of a cold worked metal structure
below its melting temperature lead to great reduction in its
strength and hardness.
28- Anterior restorative materials should have a smooth and
polished surface.
29- Grain bonders represent areas of high state of energy.
30- Impression material should be remover by sharp snap
removal .
31- Cold working of metals or alloys leads to increase in its
strength properties.
32- High thermal conductivity of metals.
33- The percene of nucleating agents during cooling of
metals increases its strength.
34- The fracture of denture base under cyclic loading.
35- Slow cooling of dental gold alloy restoration ( 64%88%) gold , gives rise to a stronger material than a quickly
cooled one.
36- A large metallic filling should be preceded by an
insulting base .
37- Slow cooling of dental gold alloy restoration below the
solidus temperature increases its strength and hardness.
38- Some material are easily elastically deformed.
39- Perception of super lattice Au Cu gives improved
properties than that of super lattice Au Cu3 in gold alloys.
40- Florescent lamps shouldn’t be used during shade
selection.
41- Denture lining materials are flexible during their service
in patient mouth.
42- Addition of inorganic fillers to polymer structure.
43- High casting pressure is generally required for bas metal
alloy.
44- The modulus of elasticity of dental gold alloys doesn’t
change by heating.
45- Low density could be advantages and disadvantages.
46- Stress maybe destructive by time in certain condition.
47- Homogenization is an essential procedure after casting
solid solution alloy with a wide melting range.
48- The restoration shouldn’t be harder than tooth structure.
49- Two solids one looks dull and opaque than the other.
50- Corrosion resistance of cold worked metal or alloy is
lower than the corresponding cast one.
51- The use of AuCu eutectic in the solid alloy for joining
metals.
52- Discolored margin, recurrent caries and and
hypersensitivity may occur in an old esthetic restoration.
53- Copper is better than silver as an alloying element for
gold.
54- Value is most important parameter in color selection.
55- Occurrence of coring phenomenon is solid solution
alloy.
56- Ceramic have high melting point.
57- Grain bounder are the site of corrosion attack.
58- Modulus of elasticity should be match between tooth
and filling material.
59- Yield stress of a material is more important than
ultimate stress.
60- Prolonged heating of gold alloy is unnecessary during
casting.
61- The polymorphic forms of silica have different physical
properties.
62- Cast metal have higher elongation % than wrought
metals.
63- Shade guide comparisons shouldn’t exceed 5 seconds.
64- Some material are easily plastically deformed.
65- Ceramic are heat resistant.
66- Corrosion resistance of cold worked metal is lower than
the corresponding cast one.
67- Hard material is advantage and disadvantage.
68- Any cold worked structure should be annealed before
insertion in oral cavity.
69- An endodontically treated tooth appears more dull.
70- Metal are opaque.
71- Not all metals form a destructive oxide layer on its surface.
72- Al, Cr and Ti are able to form a protective oxide layer with
special characteristics.
73- Metals have high density.
second part/ compare between
1- Protective and destructive oxide layers formed by
different metals.
2- Effect of cross linking and plasticizers on polymer
properties.
3- Crystalline solid and amorphous solid.
4- Brittle and ductile material.
5- Atomic and molecular solid.
6- Thermoplastic and thermoset polymers.
7- Displacive and reconstructive transformations.
8- Elastic and plastic deformation.
third part/ what will happen if
• Anode / Cathode ratio increased.
Fourth part/ state the clinical significant of
1- Clinical significant of modulus of elasticity.
2- Density.
3- Thermal conductivity
4- Heat of fusion
5- Coefficient of thermal expansion and contraction.
Fifth part/ Mention_Enumrate
1- Different method of shaping metals.
2- How can cathode/Anode ratio effects rate of corrosion.
3- Factor effecting grain size of cast metal.
4- Factors effecting grain size
5- Effect of cross linking on polymer properties.
6- Example for dry corrosion.
7- Effect of co-polymerization on polymer properties.
8- Affect of surface tension of the adhesive on wetting
9- Factors associated with polymerization reaction.
10- Component of electrolyte cell.
11- Importance of primer in bonding to dentine.