01 November, 2008

2nd BDS Dental Materials

402
B.D.S. DEGREE EXAMINATION – FEBRUARY, 2008
FIRST BDS EXAMINATION
DENTAL MATERIALS & METLLURGY

Time : 3 Hours Max. Marks : 70
Note: Answer Part A & B in separate answer books. Questions in Part’A’ should not be answered in Part’B’ and vice versa. Otherwise they will not be valued.
Answer all questions.
PART – A (35 MARKS)

Classify Impression Materials. Describe the Composition, setting 9
reaction, manipulation of Impression Compound.

WRITE SHORT NOTES ON: 4x4=16
Light cure Composite resin
Hygroscopic setting Expansion
Composition of Alginate Impression material
Duplicating Materials

WRITE BRIEFLY ON: 5x2=10
Crosslinking agents for Acrylic resin
Separating Media
Polyurethane polymer
Soft liner
Ductility and Malleability

PART – B (35 MARKS)

Classify Dental Cements. Add a note on Glass ionomer Cement. 9

WRITE SHORT NOTES ON: 4x4=16
Zinc Oxide Eugenol Cement
Stages of firing of Dental Porcelain
Metal-Ceramics
Abrasives and Polishing agents

WRITE BRIEFLY ON: 5x2=10
Annealing
Mechanical Trituration
Divestment
Flux
Nitinol
- - -
DENTAL MATERIALS AND METALLURGY-FEBRUARY-2006 Time:3hours -Marks: 70
Part-A
1. Classify composite resins and describe in detail the composition, properties and uses of hybrid composites=9m
2. Write short answers on: 4 x 4 =16m; a) Free radical polymerization
b) Composition and properties of alginate impression material
c) Setting reaction and chemical stages in setting of gypsum d) Stress-Strain curve
3. Write briefly on: 5 x 2 =10m; a) Significance of fusion temperature of impression compound
b) Non-eugenol impression paste c) Fissure conditioners d) Activators and intiator in cold acrylic resins
e) Composition of Additions Silicone impression material
Part-B
4. Classify Dental cements according to the use and give in detail the composition, setting reaction and properties
of zinc polycarboxylate cements=9m
5. Write short answers on: 4 x 4 =16m; a) Properties of Dental amalgam b) Types of Direct filling gold
c) Stabilization and sensitization of stainless steel d) Porosites in dental casting
6. Write brief answers on: 5 x 2 =10m; a) Sticky wax b) Softening heat treatment c) Uses of Titanium
d) Polishing agents for cast restorations e) Giazing


AUGUST-2005 (New Regulations)
Part-A
1. Enumerate the final impression materials for edentulous arches and write about composition, manipulation and
properties of the Zinc Oxide Eugenol Impression pastes =9pages2. Write short answers on: 4 x 4 =16marks; a) Curing cycles for heat cure acrylic resin
b) Biocompatibility of Dental Materials c) Separating media used in dentistry d) Die stone
3. Write briefly on: 5 x 2 =10marks; a) Define Glass transition temperature b) Contents in composite resins
c) Mention activating systems for autopolymerising resins d) Define elasticity and stiffness
e) Drawbacks of alginates

Part-B
4. Classify silver amalgam alloys. Write in detail composition and setting reaction of high-copper silver alloys=9m
5. Write short answers on: 4 x 4 =16marks; a) Glass ionomer cement b) Sprue-formers
c) Ideal requirements of Dental solder d) Factors affecting rate of abrasion
6. Write brief answers on: 5 x 2 =10marks; a) Define and give the purpose of degassing gold foil
b) Purpose of condensation of amalgam mass in cavity
c) Contents in Zinc Polycarboxylate cement powder and liquid d) Die hardener and die spacer
e) Define sensitization and stabilization


MAR/APR.2005.
Part-A
1. Ennumerate various synthetic resins and discuss the composition and manipulation and uses of Heat-cure acrylic
resins=9marks
2. Write short notes on: 4 x 4 =16marks; a) Polyether rubber base impression material
b) Composition of composite resins c) Dental stone d) Pit and fissure sealants
3. Write briefly on: 5 x 2 =10marks; a) Ductility and Malieability b) Hygroscopic expansion
c) Setting of polysulphide rubber base material d) Di-vestment e) Wet-field technique
Part-B
4. Classify Dental amalgam alloys and discuss the composition, setting reaction and advantages of High-Copper
amalgam alloy =9marks
5. Write short answers on: 4 x 4 =16marks; a) Liners and bases for dental restoration b) Metal-ceramic bond
c) Abrasive agents used in dentistry d) Contents in Dental Casting Gold alloys
6. Write brief answers on: 5 x 2 =10marks; a) Composition of inlay wax b) Types of Dental Ceramics
c) Setting reaction of Zn-PO4 Cement d) Cohesive Gold e) Flux and anti flux




OCTOBER, 2004. (New Regulations)





Part-A
1. Classify impression materials. Describe the composition, setting reaction and factors affecting setting time of
Zinc Oxide Eugenol paste =9m
2. Write short answers on: 4 x 4 =16marks; a) Duplicating materials b) Die stone c) Curing cycles
d) Dimensions of colour3. Write briefly on: 5 x 2 =10marks; a) Syneresis and Imbibition b) Synthetic Gypsum
c) Coupling agents in composite resins d) Reline technique for elastomeric impressions.
e) Cross linking agents and their role in acrylic resins.






Part-B
4. Discuss various steps in casting procedure of inlay and add a note on shrinkage porosity=9m
5. Write short notes on: 4 x4 =16m; a) Admixed dental amalgam alloys b) Glass ionomer cements
c) Properties desirable in metal-ceramic alloys d) Baking stages in dental porcelain
6. Write briefly: 5 x 2 =a) Baseplate wax b) Mat gold c) Advantage of resin cements d) Nitinol e) Diamong.


















APRIL/MAY,2004
Part-A
1. Enumerate various gypsum products and write in detail about manufacturing and standardization of Dental
plaster and Dental stone =9marks
2. Write short answers : 4 x 4;a) Peripheral Tracing sticks b) Addition Silicone Rubber base impression materials.
c) Hardness d) Self care acrylic resin.
3. Write briefly on: 5 x 2 =a) Purpose of soft liners b) Mention purpose of acid etching
c) Modes of activation for polymerization d) Crazing in acrylic bases
e) Role of Trisodium phosphate in alginate
Part-B
4. Enumerate various casting investment materials and write in brief about contents, manipulation and care while
using Phosphate Bonded investment materials. =9marks
5. Write short answers on: 4 x 4 =16marks; a) Composition of dental porcelain
b) Ideal requirements of inlay casting wax c) Electro-chemical corrosion d) Creep in amalgam
6. Write briefly on: 5 x 2 =10marks; a) Purpose of die spacer b) Define carat and fineness of gold alloys
c) Vent sprues d) Contents in modeling wax e) Pumice









OCTOBER, 2003. (N.R.)
Part-A
1. Write in brief about requisites for dental resins and composition, manipulation and processing of the heart cure
acrylic resin. =9marks
2. Write short answers on: 4 x 4 =16marks; a) Duplicating materials b) Pit and fissure sealants
c) Modulus of elasticity d) Classification of resin based composites.
3. Write briefly on: 5 x 2 =10marks; a) Mention fillers in Dental Materials b) Syneresis and imbibition
c) Binders for casting investments d) Define electroplating and electropolishing e) Contents in die stone
Part-B
4. Classify Dental Cements and write in brief about recent advances in Zinc Phosphate Cement. 9marks
5. Write short answers on: 4 x 4 =16marks; a) Alloys for metal ceramics b) Fluxes used in Soldering
c) Polishing agents d) Types of Stainless Steel
6. Write briefly on: 5 x 2 =10marks; a) Cavity liners b) Back pressure porosity
c) Contents in admixed silver alloys d) Define Trituration and condensation of amalgam. e) Uses of Titanium.




APRIL,2003. (N.R.)

Part - A
1. Write in detail about composition, manipulation & disadvantages of irreversible hydrocolloid impression materials=9
2. Write short answers on: 4 x 4 =16marks
a) Gypsum bonded investments for casting b) Curing cycles c) Soft liners for dentures
d) Contents and their role in composite resins
3. Write brief answers on: 5 x 2 =10marks a) Name any two pit and fissure sealants
b) Uses of peripheral tracing compound c) Crazing in acrylic resin
d) Wet and dry strength e) Test for measuring setting time

Part-B
4. Enumerate various dental casting alloys. Write in brief about content of gold alloys =9marks
5. Write short answers on: 4 x 4 =16marks
a) Ideal requirements of dental casting waxes. b) Casting defects c) Phosphate banded investment
d) Firing of dental porcelains
6. Write briefly on: 5 x 2 =10m; a) Any four polishing agents b) Define Heat hardening and softening treatment c) Contents of cavity varnishes d) Types of stainless stell e) Direct filing gold various types

OCTOBER, 2002
Part-A
1. Classify impression materials and describe in detail about contents, setting and properties of silicon rubber base impression material=9marks
2. Write short answers on: 4 x 4 =16 a) Stress and Strain relation b) Die stone
c) Autopolymerising Acrylic resins d) Causes for porosities in resins
3. Write briefly on: 5 x 2=10m a) Define hygroscopic expansion
b) Physical stages in mixing of heat cure acrylic resin
c) Uses of agar-agar d) Define Imbibition & Syneresis e) Mention accelerator & retarder for ZOE paste.


Part-B
4. Classify Dental Amalgam alloys and write in detail about admixed Silver alloys =9marks
5. Write short answers on: 4 x 4=16 a) Ideal requirements of Orthodontic wires
b) Composition of various chrome-cobalt alloys c) Compensation of Casting Shrinkage d) Compomers
6. Write briefly on: 5 x 2 =10marks
a) Mention methods of melting of dental casting alloys
b) Define and give the cause of ‘Suck back’ porosities in casting
c) Uses of Tungsten Carbide d) Mention types of bond between porcelain and metal
e) Uses of modelling wax.











10th August, 2001. Time: 3hrs, Marks-80 - Answer Part A & B in separate answer books. Answer all questions –Draw diagrams wherever necessary
Part-A
1. Classify and give ideal requirements of impression materials and discuss in detail contents, manipulation and
merits of Poly vinyl siloxane impression material –10marks
2. Write short Notes: 6x5=30marks
a) Pit & fissure sealants b) Autopolymerising resins c) Hygroscopic expansion d) Hardness tests e) Agar-agar
Part-B
1. Classify Dental amalgam alloys. Describe composition and properties of high copper containing silver alloys. Add a note on setting reaction upon trituration -10marks
2. Write short Notes: 6x5=30marks
a) Ideal properties of orthodontic wires b) Welding in dentistry c) Wet corrosion d) Meta-ceramic alloy
e) Glass ionomer cement f) Pumice



FEBRUARY, 2000.
Part-A
1. Give the classification of Waxes. Write in detail about inlay casting wax =10marks
2. Write short notes on: 6x5=30marks
a) Asbestos liner b) Spruing c) Gold alloys d) Eutectic solutions e) Wrought metals
f) Stages in Polymerization reaction
Part-B
3. What is amalgam? Give the classification properties and manipulation of dental amalgam =10marks
4. Write short notes on: 6 x 5 =30m=a) Heat cure acrylic b) Zincoxide eugenol paste c) Dental Plaster
d) Chromium-cobalt alloys e) Shrink-free ceramics



OCTOBER, 1999.
Part-A
1. What are gypsum products? Write in detail about the manipulation and properties of alpha Hemihydrate
material=10marks
2. Write short notes on: 6 x 5 =30marks
a) Ductility and malleability b) Tarnish and corrosion c) Soldering
d) Synersis and imbibition e) Die and counter die materials f) Calcium Hydroxide
Part-B
3. What are base metal alloys? Describe different base metal alloys used in Dentistry?
4. Write short notes on: 6x5=a) Silicate Cement b) Admixed alloys c) Cavity Varnishes d) Abrasives
e) Modelling wax f) Pickling solutions.



10th April, 1999.
Part-A
1. Classify impression materials and discuss in detail about composition, manipulation and properties of
elastomeric impression material =10marks
2. Write short notes on: 6x5=30marks
a) Wanderval forces b) Separating media c) Hydroscopic expansion d) Polymerization reaction
e) White gold alloys f) Pit and fissure sealants
Part-B
3. What do you understand by ‘luting agents’? Mention the different luting agents and discuss the requirements
of luting agents =10marks
4. Write short notes on: 6x5=30marks
a) Stainless steel alloys b) Agar-Agar material c) Cermet d) Copper amalgam
e) Polishing agents f) Rake angle






OCTOBER, 1998.
Part-A
1. Write in detail about composition and manipulation and properties of irreversible hydrocolloid impression
material =10marks
2. Write short notes on: 6x5=30marks
a) Stress and Stain b) Biologic consideration for selection of dental materials
c) Porosities in acrylic resin d) Tissue conditioners
e) Casting Waxes f) Accelerators and retraders to gypsum products.
Part-B
3. Classify noble metal costing alloys. Discuss the typical compositions of noble metal casting alloys =10marks
4. Write short notes on: 6x5=30marks
a) Ideal requirements of base and cavity liners b) Zinc polycarboxylate cement
c) Electro polishing d) Compensation of casting shrinkage f) Diamong as an abrasive



APRIL, 1998
Part-A
1. Enumerate various denture base material mention ideal requirements of Denture base resins and stages in polymerization-10marks
2. Short Notes: a) Impression Plaster b) Duplicating Materials c) Creep d) Pit and fissure sealants
e) Imbibition and Syneresis f) Filters in Dental Materials –6x5=30marks
Part-B
3. Discuss in detail composition of Dental Porcelains. Add a note on Glazing –10marks
4. Short Notes: a) Resin Cements b) Fluxes for soldering c) Cavity liners d) Casting defects
e)Role of ingradiants in noble metal casting alloys
f)Composition & setting reaction of Phosphate bonded investments





OCTOBER, 1997.
Part-A
1. What is Elastomer? Enumerate various elastometric impression materials and write in detail about addition silicone rubber base materials –10marks
2. Short notes on any FIVE =5x5=25marks
a) A.D.A. – Specification b) Microfilled composite resin c) Peripheral tracing compound
d) Hardness tests e) Die materials f) Composition of cold cure acrylic resin
Part-B
3. Classify Dental amalgam alloys. Write in detail about composition and advantages of High copper containing silver amalgam alloys –10marks
4. Short notes: 5 x 6 =30marks a) Glass ionomer cement b) Requirements of metal for metal ceramics
c) Factors affecting rate of abrasion
d) Hygroscopic expansion e) Modelling waxes f) 18-8 stainless steel




APRIL, 1997.

Part-A
1. Classify investment materials. Describe in detail gypsum Bonded investment –10marks
2. Short Notes: a) Copper rich Amalgam alloy b) Sprue c) Soldering d) Polyether impression materials
e) Inlay Wax =5 x 5 =25marks

Part-B
3. Give Ideal requirement of denture Base Materials. Explain the defects seen in Heart cure acrylic resin denture base=10m
4. Short notes on : a) Denture reliners b) Poly carboxylate cement c) Microfilled composite resin
d)Polishing agents e)Setting reaction in Alginates
f)Advantages of Dental Porcelain as restorative material =6x5=30










OCTOBER, 1996.
Part-A
1. Classify Waxes. Write in detail about inlay waxes. =10marks
2. Short Notes: a) Direct bonding cement b) Gypsum bonded investment c) Sprue d) Polishing agents
e) Mat Gold f) Strength and hardness =5x5=25marks
Part-B
3. What are heat cure resins? Give the composition, properties and manipulations of Heat cure Resins =10m
4. Short Notes: a) Chrome-Cobalt b) Irreversible impression material c) Tarnish d) Dental plaster
e) Model Cement f) High cure Amalgam 5 x 6 =30marks