1. Which of the following is NOT a packaging for dental materials? a. 3 components mixed in an auto-mixing syringe b. 2 components mixed in a machine mixer c. 1 component that set when water is added d. A powder and liquid that are missed by spatulation
2. What is the setting time? a. Time elapsed from the onset of mixing until the beginning of setting b. Time elapsed from the end of mixing until the end of the working interval c, Length of the working interval d. Length of the setting interval e. The elapsed from the onset of mixing until the end of the setting process
3. Which ONE of the following required VLC (visible light curing) for setting? a. Dental amalgam b. Polyvinyl siloxane c. Calcium sulfate hemihydrate d. Traditional glass ionomer e. Posterior composite
4. Which ONE of the following procedures does NOT involve a loss of gloss during setting? a. Pit and fissure sealants b. Plaster c. Glass ionomer cement e. Alginate
5. What is the linear coefficient of thermal expansion for tooth structure? a. 5ppm/C b. 10ppm/C c. 15ppm/C d. 20ppm/C e. 60ppm/C
6. Which ONE of the following is a poor thermal insulator? a. Dentin b. Enamel c. Gold alloy restorations d. Glass ionomer cement e. Ceramic inlays
7. Which one of the following is most important for good pulpal insulation? a. Liners that are good thermal insulators b. Dentin scaling c. 1-2min thickness of insulation below a restoration d. Low optical conductivity e. High density
8. Which of the following terms is not related to color? a. Fluorescence b. Luminance c. Dominance d. Translucency e. Resilience
9. Which of the following is NOT associated with electrochemical corrosion events? a. Stress b. Crevices c. Plaque d. Passivation e. Metamerism
10. Engineering stress is computed as: a. Applied load divided by the original cross-sectional area of the object b. Applied load divided by the volume of the object c. Modulus multiplied by the plastic deformation d. Difference between the total strain and the plastic strain e. Percent elongation
11. Engineering strain is computed as: a. Change between the initial and final strain divided by the time b. Area under the stress-strain curve c. Modulus multiplied by the plastic deformation d. Applied load divided by the original cross-sectional area of the object e. Deformation divided by the original length of the object
12. What is another name for a material’s modulus? a. Stiffness b. Resilience c. Toughness d. Fatigue resistance e. Strain rate sensitivity
13. Loading a restoration beyond the materials’ elastic limit produces a. Only plastic deformation b. Only elastic deformation c. Fatigue fracture d. Elastic and plastic deformation e. Stress relaxation
14. The point at which loading begins to produce both plastic and elastic strain at the same time is called any of the following terms except: a. Elastic limit b. Yield point c. Proportional limit d. Hardness e. Breaking point
15. Which of the following statements is not true about the Moh’s hardness scale? a. Scale involved units 1-10 b. Diamond if the hardest reference value c. Talc is the softest reference value d. Enamel is 7-8 on the scale e. Dentin is 3-4 on the scale
16. Which of the following biologic reactions is concentration-dependent? a. Hypersensitivity b. Fibrous capsule formation c. Toxicity d. Inflammation e. None of the above
17. Which of the following phases in dental amalgam restorations is most prone to electrochemical corrosion? a. Ag-Sn b. Ag-Sn-Cu c. Sn-Hg d. Cu-Sn e. Ag-Hg
18. Which of the following phases in dental amalgam restorations has the best mechanical properties and highest corrosion resistance? a. Ag-Sn b. Cu-Sn c. Sn-Hg d. Ag-Hg e. None of the above
19. Which of the following mixing methods permits the escape of dental amalgam vapor? a. Mixing in a mortar mercury pestle b. Proportioning mercury and allow into a friction-fit-capsule c. Triturating pre-capsulated allow and mercury d. A cover over the mixing arms on a triturator e. None of the above
20. Low copper dental amalgam allows involved what ranges of copper in their compositions? a. 0.1-0.5% b. 0.5-1% c. 1-5% d. 6-12% e. 12-15%
21. Which of the following is not true about high copper dental amalgam restorations? a. Better corrosion resistance than low copper dental amalgams b. Contain both Sn and Ag composition as well c. Produce excessive creep d. Restorations are more brittle than low copper versions e. Contain 12% to 30% copper in the original alloy composition mixed with Hg
22. What is the melting temperature of the Ag-Hg matrix phase in a set dental amalgam restoration? a. 127 C b. 222 C c. 327 C d. 427 C e. 527 C
23. Which of the following is the criterion for a failed high copper dental amalgam restoration? a. Accumulation of black or green tarnish on the exposed surface b. Marginal ditching along occlusal margins c. Creep of the restoration out of the oral cavity preparation in proximal areas d. Wear facets along the occlusal contact areas e. None of the above
24. Surface wear on posterior dental composite restorations should be managed by a. Replacing the composite with an amalgam e. Replacing the worn areas with resin-modified glass ionomer c. Replacing the restoration with a new high-strength ceramic d. Adjustments of the occlusal of the opponent tooth e. Resurfacing of the old composite with a new composite
25. Which of the following procedures is standard for conditioning tooth structure before bonding procedures for composite restoration? a. Phosphoric acid conditioning of enamel only b. Phosphoric acid conditioning of dentin only c. Phosphoric acid conditioning of enamel and dentin d. EDTA conditioning of enamel and dentin e. Polyacrylic acid conditioning of enamel and dentin
26. The smear layer is all the following except a. 2-5 micron layer of debris from enamel to dentin b. Primarily hydroxyapatite in composition c. Loosely adherent to tooth structure with about 4-6 MPa of bond strength d. Capable of partially sealing dentinal tubules e. Soluble in HEMA in priming agents for dentin bonding procedures
27. Strong bonding to dentin requires: a. Extensive conditioning b. Very dry dentin c. Pre-application of Chlorhexidine d. Scrubbing during conditioning e. Hybrid layer formation
28. Which one of the following items is NOT related to the others? a. Resin-interpenetration zone b. Hybrid layer c. Resin inter-diffusion zone d. Collagen impregnation zone e. Silanation zone
29. Water-miscible acrylic monomers are most likely found in: a. Liquid conditioners b. Gel conditioners c. Pit and fissure sealants d. Dentin primers e. Dentin adhesives
30. Which of the following is NOT required for good dentin bonding? a. Conditioning b. Dentin with a glistening appearance after conditioning c. Dentin with a glistening appearance after priming d. Use of adhesive e. Air thinning to eliminate excess primer or adhesive
31. Recent version of dentin bonding systems for composites are simpler because: q. Conditioning is not required for bonding b. No mixing of composites is required c. Bonding agents have already been added directly to the composite d. Only one layer is applied rather than 2-5 coats e. There are 2 steps rather than 3 in the procedure
32. Which of the following restorations does not require protection with Vaseline during APF application procedures? a. High-strength ceramics b. Hybrid dental composites c. Resin-modified glass ionomers d. PFM e. Cast gold
33. Which of the following is the LEAST effective method of sealing a cavity preparation? a. Copalite b. Dentin bonding system c. amalgam bonding system d. Glass ionomer liner e. Bonded composite cement
34.Which one of the following constituents may produce palliative action if it can diffuse to the dental pulp? a. Calcium hydroxide b. Eugenol c. HEMA d. BIS-GMA e. 4-META
35. Which one of the following cavity preparation liners provides no practical thermal insulation for the pulp? a. Glass ionomer liner b. Zinc phosphate cement base c. Polycarboxylate cement base d. Calcium hydroxide liner e. Dentin bonding systems
36. The largest component of zinc phosphate, poylcarboxylate, and ZOE dental cement is: a. Water b. Silica c. Mineral acid d. Eugenol e. Zinc oxide
37. Glass ionomer cement may chemically adhere to tooth structure as a result of what cement? a. Aluminum ions release from the particles of cement powder b. Chelation of calcium by ionized polyacrylate groups c. Electrostatic attraction to aluminosilicate powder d. Hydration of the set of materials e. Fluoride ion release
38. In dental composites, increasing the powder to liquid ratio of components produces: a. Lower strength b. Higher modulus c. Increased water absorption d. Improved toughness e. Increased solubility
39. Compomers are: a. Very slightly modified glass ionomers b. Composites that set but a new chemical reaction c. Composites that contain excessive free monomer after visible light-curing d. Extensively modified glass ionomers approaching composites e. Biologically compatible glass ionomer
40. The principle advantage of resin-modified glass ionomers over traditional ones is: a. Immediate finishing is possible d. Mixing is much easier c. All post-operative sensitivity is eliminated d. Better adhesion to tooth structure e. No shrinkage occurs on setting
41. The major use of glass ionomer restorations is for which application? a. Class III restoration in older adults b. Thin, saucer-shaped Class V restorations c. Class II restorations in children d. Class IV restorations in permanent teeth e. Root caries lesions
42. In addition to the hardness of an abrasive material, what is also a key factor in the cutting effectiveness of the abrasive? a. Particle size of the abrasive b. Fluoride in the abrasive paste c. Cooling water during the procedure d. Vibration of the paste e. Thickness of the abrasive paste against the surfaces
43. All of the following are flexible impression materials EXCEPT: a. Alginate b. Polyether c. Polyvinyl siloxane d. Polysulfide e. ZOE
44. Which ONE of the following impression materials does not set via a chemical reaction? a. Agar-agar hydrocolloid b. ZOE c. Polysulfide d. Polyether e. Polyvinyl siloxane
45. which ONE of the following impression materials may be machine mixed? a. Alginate b. ZOE c. Polyether d. Silicone e. Polysulfide
46. What is the removable piece from a working cast that contains the prepared tooth information called? a. Die b. Master cast c. Negative d. Duplicate e. Model
47. What is the chemical composition of gypsum products that have fully reacted with water/ a. Calcium sulfate hemihydrate b. Calcium sulfate monohydrate c. Calcium sulfate dihydrate d. Calcium sulfate trihydrate e. Calcium sulfate tetrahydrate
48. Gypsum powder that is to be reacted to form working casts is composed primarily of: a. Aluminosilicate glass b. Calcium sulfate hemihydrate c. Calcium carbonate d. Sodium fluoride e. Calcium phosphate
49. How much water of reaction is required for the setting of 100 grams of calcium sulfate hemihydrate powder? a. 10ml b. 18ml c. 24ml d. 32ml e. 50ml
50. What is the major difference between plaster and stone powder? a. Degree of water hydration b. Color c. Different chemical reactions on setting d. Different powder particle packing e. Different setting times
51. What is the reason that different types of gypsum-based powders require different amounts of water for mixing? a. Powder particles pack differently b. Different reactions are involved c. Some powder particles are porous and imbibe water d. Water controls the viscosity and flow-ability of the mixture e. Some materials are naturally more hygroscopic in air
52. What is the reason that wax application to dies to create patterns for onlays and crowns should be accomplished slowly and in thin layers allowing each increment to cool? a. Low elastic modules of wax b. Poor adhesion of wax to the dies c. Distortion from thermal contraction d. Susceptibility to water absorption e. Porosity
53. What is the major component in most dental waxes? a. Carnauba wax b. Colorant c. Paraffin d. Rosin e. Beeswax
54. Dental inlay waxes are primarily formulated with what goal in mind? a. High modules b. Minimizing the thermal expansion coefficient c. Complete pyrolysis on heating to CO
and water d. Color matched to application or use e. Cost
55. What is the classification scheme for dental investment materials? a. Composition of the matrix phase b. Amount of water involved in mixing the materials c. Extent of expansion on heating d. Compatibility with casting alloy types e. Ranges of strength
56. What is the investment material used primarily with high gold casting alloys for all metal crowns? a. Gypsum bonded investment b. Silicate bonded investment c. Phosphate bonded investment d. Magnesia investment e. Ceraming investment
57. What is the cartage of an alloy that is 50% Au by weight? a. 10K b. 12K c. 20K d. 24K e. 50K
58. In high-gold casting alloys, which element is primarily responsible for good corrosion resistance? a. Au b. Cu c. Ag d. Zn e. Pd
59. In high-gold casting alloys, which element is primarily responsible for counteracting the effect of copper on the color? a. Au b. Pr c. Ag d. Zn e. Pd
60. What is the effect of chromium oxide for stainless steel alloys? a. Aid in production of alloy b. produced the shiny color for the alloy c. Increases the module d. Passivating film that prevents corrosions e. Material for polishing stainless steel ortho appliances
61. Which of the following materials does not involve passivation? a. Stainless steel b. Cr-Ni c. Cr-Co d. Titanium e. Lithium aluminosilicate glass
62. The difference between soldering and brazing is: a. Temperature b. Type of solder c. Method of fluxing d. Acid pretreatment e. corrosion resistance
63. Which one of the following terms is related to dental solders? a. 650 fine b. Low gold alloys c. Passivation d. Welding e. Vitrification
64. Gold alloys for porcelain-fused-to-metal applications versus all gold crown applications require: a. Better electrochemical corrosion resistance b. Lower thermal conductivity c. Whiter color d. High melting temperatures e. None of the above
65. Nickel sensitivity could occur with all the following compositions except: a. Stainless steel ortho wires and brackets b. Stainless steel crown on primary teeth c. Ni-Cr PFM restorations d. Co-Cr partial dentures e. All the above
66. What is the general incidence of nickel sensitivity for men? a. 1% b. 4% c. 8% d. 11% e. 20%
67. What are the main components in typical dental appliances? a. Silica, calcium carbonate, alumina b. Silica, alumina, potassium oxide c. Alumina, zinc oxide, fluoride d. Alumina, potassium oxide, calcium oxide e. Calcium oxide, magnesium oxide, chromium oxide
68. What one of her following is NOT an advantage for dental ceramics? a. Excellent color and translucency b. Low coefficient of thermal expansion c. Low plastic deformation d. Low thermal and electrical conductivity e. High hardness
69. Which one of the following is true about traditional dental cements? a. Requires mixing in a triturator only b. Reactions are endothermic c. Based on mixture of acidic liquids with basic powder components d. Materials are extremely hydrophobic e. Set materials are general stronger than dental composites
70. Which of the following cements contains zinc oxide as part of the chemical compositions? a. ZOE b. EBA-modified ZOE c. Zinc phosphate d. Polycarboxylate e. All the above
71. Which of the following dental cement compositions required staged additions of powder to the liquid during mixing on a chilled glass slab to control the reaction? a. Polycarboxylate cement b. Composite resin cement c. Resin-modified glass ionomer cement d. Zinc phosphate cement e. Zinc oxide Eugenol cement
72. Denture bases are fabricated from acrylic resin based primarily on what monomer? a. Ethyl methacrylate b. Methyl methacrylic c. BIS_GMA d. UDM e. HEMA
73. Acrylic resin teeth are preferred for denture construction because of their: a. Light weight b. Bondability to the denture base c. Wear resistance d. Ease of cleaning e. Excellent esthetics
74. Which is the MAJOR reason that tissues conditioner used with denture bases quickly because harder over several days? a. Desorption of plasticizer into the patients saliva b. Mineralization of the material by calcium phosphate from the saliva c. Continuing chemical reactions in the tissue conditioner d. Chemical effects if cleaning solutions on the tissue conditioner e. Fungal growth along the surface of the tissue conditioner
75. CAD/CAM operations collect detailed tooth surface information using: a. Micro-tomography b. Automated contact digital profilometry c. Laser profilometry d. Intraoral digital cameras e. Silverized impressions
76. Which if the following applications is most challenging for CAD/CAM and copy-milling procedures? a. Inlays b. Onlays c. Crowns d. Bridges e. Veneers
77. Which of the following materials is most suitable for CAD/CAM restorations? a. Dental composite b. Dental porcelain c. Dicor d. Dicor MGC e. Gold alloys
78. What is copy-milling? a. Production of secondary dies for indirect procedures b. production of replacements for failed CAD/CAM restorations c. Generation of milled restoration by copying a master models d. Generation of standard sized inlays and onlays e. Method of mass production of denture teeth
79. Where is wear most likely with a CAD/CAM MOD inlay restoration? a. Interprox contact areas b. Occlusal surfaces c. Marginal ridges d. Cemented margins e. Cavosurface inlay margins
80. Which one of the following is the main reason for milled ceramic restoration failure? a. Poor fatigue fracture resistance b. Color change over time c. Failure of composite resin bonding system d. Inadequate hardness e. Poor wear resistance
81. What type of dental materials will MOST likely disappear due to increased technology: a. Glass ionomers b. Dental composites c. CAD/CAM or copy-milled restorations d. Gold alloy crowns e. All-ceramic crowns and bridges
82. With time, dental materials wear. Amalgam fillings can lose their marginal integrity to allow the penetration of fluid between the restoration and tooth surface. This phenomenon is called: a. Imbibition b. Syneresis c. Percolation d. Wetting e. Creep
83. Your patient has a gag reflex but study models are needed for a treatment plan. Which of the following procedures might help better control the gag reflex? a. Decrease the water temperature b. Increasing the water temperature c. Slowly adding mixed impression material to the tray d. Not placing the impression material at the posterior segment of the tray
84. With respect to dental properties, strain measures resilience. Another property is stress, which measures expansion. a. Both statements are TRUE b. The first statement is TRUE, the 2 nd is FALSE c. The first statement is FALSE, the 2 nd is TRUE d. Both statements are FALSE
85. Of the metals in an amalgam filling, which attracted tin away from mercury? a. Zinc b. Silver c. Copper d. Gold e. Lead
86. An example of an impression material that sets by a physical reaction is agar agar. An example of an impression material that sets by a chemical reaction is zinc oxide and eugenol. a. Both statements are TRUE b. The first statement is TRUE, the 2 nd is FALSE c. The first statement is FALSE, the 2 nd is TRUE d. Both statements are FALSE
87. Undertrituration affects the set of an amalgam filling. Which of the following is NOT a result of undertrituration? a. Amalgam can fracture b. Amalgam appears dull c. Amalgam hardens too quickly d. Amalgam appears crumbly e. Amalgam appears like a mirror
88. The dental metal alloy element that causes the greatest amount of allergic reaction is a. Mercury b. Tin c. Silver d. Copper e. Nickel
89. Dental materials are gauged by their different properties. Knoop’s test measures a. Resilience b. Hardness c. Malleability d. Dynamic modulus e. Flexibility
90. A patient should return to the dental office 24 hours to 7 days after the placement of an amalgam.
Which of the following polishing agents is used to polish amalgam fillings? a. Pumice b. Rouge c. Tin Oxide d. Strips of alumina
91. RDHs can assist in the prevention of disease with the placement of sealants. Which of the following reason accounts for the greatest number of sealant failures? a. Water contamination b. Improper set time c. Acid not properly rinsed d. Tooth not properly etched e. Clinician inaccuracy
92. Some impression materials are rigid while others are flexible. All the following are flexible impression materials except one. Which one is the EXCEPTION? a. Polysulfide b. Silicone c. Polyether d. Polyvinyl siloxane e. Zinc oxide and eugenol
93. Water temperature can affect the set-time of an alginate impression. This process of setting up of an alginate impression is called a. Imbition b. Syneresis c. Gelatin d. Polymerization e. Sintering
94. Permanent molars should e sealed as soon as possible after they erupt before the grooves and pits are affected. The most appropriate time to perform this service is a. 1,3 grades b. Kinder and 6 th c. 1,6 grades d. 2,7 grades
95. Some types of impression materials are more accurate than others. Which of the following impression materials is the MOST accurate? a. Alginate b. Plaster c. Silicone d. Agar agar
96. Grit is used in the dental operatory as well as in the dental lab. The word grit refers to a. Shape b. Hardness c. Size d. Firmness e. Strength
97. Before applying sealant, a clinician will use an acid etch, which provides a surface that allows for a
____ bone. a. Chemical b. Physical c. Micromechanical d. Macromechanical e. Thermal
98. A restoration varnish or liner performs all the following functions except one. Which one is the
EXCEPTION? a. Protects against thermal conduction b. Reinforced the floor of the preparation c. Increases the ingress of fluids d. Seal dentinal tubules
99. an impression material that sets by both a chemical and physical reaction is a. Agar agar b. Alginate c. Poly sulfide d. Polyether e. Plaster compound
100. During a long procedure, zinc oxide and eugenol were not immediately removed from the spatula.
Which of the following would best remove the set material? a. Wax solvent b. Benzalkonium chloride c. Soap and water d. Orange solvent
101. Iontophoresis uses an electrical current to impregnate desensitizing agents into a tooth surface.
When fluoride is used with this electrical device, what action takes place with the tooth surface? a. Fl-ion penetration incorporates 2-6x more fluoride into tubules b. Ameloblastic activity is stimulated c. Fl applied with an electric current provides short-term relief d. Fl applied in this manner stimulates secondary dentin formation to insulate the tooth
102. If an impression is not poured up within 60min, ____ can occur a. Imbibition b. Creep c. Cohesion d. Retardation e. Syneresis
103. A disinfectant not acceptable for use as a laboratory disinfectant is a. Iodophors b. Glutaraldehydes c. Quarternary ammonium compounds d. Chlorine compounds
104. If a fork should touch an amalgam and a sudden pain is produced in the tooth, which of the following occurs? a. Corrosion b. Adhesion c. Burnishing d. Galvanization
NATIONAL BOARD REVIEW, DH227 Lisa Mayo, RDH, BSDH
“Bumps” on a study model are the result of: a.
Voids in the impression b.
Inadequate mixing of the alginate c.
Taking too long to pour the stone d.
Using too much water in the stone mix
The best way to influence the setting time of alginate is to: a.
Add borax b.
Add potassium sulfate c.
Alter the temperature of the water d.
The setting time of alginate can’t be manipulated
The principle ingredient of reversible hydrocolloid is: a.
Sodium alginate d.
The loss of solvent by a solute is called: a.
None of the above
When used as a base, zinc phosphate’s greatest physical characteristic is its: a.
Adhesive quality d.
The liner which best stimulates the development of reparative dentin is: a.
Oil of cloves b.
Copal varnish c.
The most frequent cause of sealant failure is: a.
Oil contamination b.
Poor tooth selection c.
Inadequate curing light d.
Contamination by saliva
A cement base is utilized on badly decayed teeth before the filling is placed in order to insulate and protect the pulp. a.
Both the statement and reason are true b.
Both the statement and reason are false c.
The statement is true, but the reason is false d.
The statement is false, but the reason is true
To delay the setting time of gypsum a.
The water must be decreased b.
Borax can be added to the mix c.
The mix should be stirred vigorously d.
Potassium sulfate can be added to the mix
When converting from a sol to a gel, a reversible hydrocolloid undergoes what kind of reaction? a.
It does not undergo any reaction
The setting time of gypsum could be shortened by? a.
Excessive mixing b.
Mixing with less water c.
Adding potassium sulfate d.
All the above
Which of the following could be used as a final polish for gold, ceramic, amalgam, or composite restorations in the mouth? a.
Tin oxide d.
Heat can be minimized when polishing by these 3 methods: a.
Using a light touch b.
Using water as a cooling agent or lubricant c.
Using intermittent bursts with the prophy cup d.
Using firm pressure and a coarse, commercially prepared pumise
The setting expansion of a gypsum product can be reduced by: a.
Using less water in the mix b.
Using more water in the mix c.
Using stone instead of plaster d.
A Class IV restoration: a.
Includes all pits and fissures b.
Includes the incisive angle of an anterior tooth c.
Includes the proximal surface of a posterior tooth d.
Includes the gingival third of the F or L surface
A dental cement may be used as a base because it: a.
Can protect the pulp b.
Has adequate compressive strength c.
Is a poor conductor of temperature extremes d.
All the above
A newly placed silver amalgam restoration adjacent to a cast gold crown might cause: a.
The difference between an inlay and an onlay is that: a.
There is no difference between an inlay and an onlay b.
An inlay is made of silver and an onlay is made of gold c.
An inlay should not exceed ½ the intercuspal distance, while an onlay covers the cusps d.
An onlay should not exceed ½ the intercuspal distance while an inlay covers the cusps
When bonding, the enamel is etched to: a.
Increase the chemical retention by increasing the bonded surface area b.
Decrease the chemical retention by decreasing the bonded surface area c.
Increase the mechanical retention by increasing the bonded surface area d.
Decrease the mechanical retention by decreasing the bonded surface area
When making a study model of stone, instead of plaster, one should: a.
Use less water b.
Use more water c.
Mix twice as long d.
Never make a study model of stone
Amalgam restoration are polished to: a.
Decrease the surface area b.
Minimize plaque accumulation c.
Make them more resistant to corrosion d.
All the above
Composite fillers include: a.
All the above
Three toothpaste components used to fight hypersensitivity include: a.
Sodium citrate b.
Potassium nitrate c.
Aluminum sulfate d.
An example of a rigid impression material would be: a.
Zinc oxide/eugenol d.
All the above
Which of the following agents should not be used to clean a metal-based partial denture? a.
Soap and warm water
How much time should elapse before a stone cast is removed from an alginate impression? a.
At least 90min
The most effective way to insulate the pulp of a tooth is to: a.
Use a liner b.
Use a base c.
Restore it with a cast gold crown d.
Restore it with a chrome-steel crown
Zinc phosphate cement is left in the deepest portion of a tooth preparation primarily to: a.
Induce secondary dentin formation b.
Provide thermal insulation for the pulp c.
Improve the retention of the amalgam filling d.
All the above
Which of the following is a disadvantage of an impression obtained with hydrocolloid? a.
High gel strength b.
High melting point c.
Excessive viscosity d.
Lack of dimensional stability
Two ways to prevent the creation of a Class II overhang include: a.
Use a base b.
Only use amalgam c.
Place a wedge interproximally d.
Use a properly shaped and placed matrix band
The easiest way to detect an amalgam overhang is with: a.
An explorer b.
A gold knife c.
A polishing disc d.
A high speed bur
Recurrent root decay is generally classified by GV Black as: a.
Class II b.
Class V c.
Class IV d.
Heat generated while polishing an alloy would most likely damage: a.
The cementum b.
The odontoblasts c.
The enamel prisms d.
The cement which has the greatest chemical affinity for enamel is: a.
Glass ionomer c.
Zinc phosphate d.
Seen in a radiograph, a composite restoration might appear: a.
Less radiopaque than an alloy d.
All the above
If high compressive strength was the single most important requirement in selecting a restorative material, the material of choice would be: a.
Glass ionomer d.
A cast metal restoration
The material of choice for a Class VI restoration would be: a.
Glass ionomer d.
A cast metal restoration
If left in water, an alginate impression undergoes what process? a.
The gypsum product with the least compressive strength is: a.
Improved stone d.
None of the above
Intraorally, a clinician may polish gold with tin oxide. Extraorally, a clinician or lab tech may polish gold with rouge. a.
Both statements are true b.
Both statements are false c.
Only the first statement is true d.
Only the second statement is true
A cantilevered bridge can be easily identified radiographically because: a.
Porcelain is radiopaque b.
It always has an open contact c.
It is always made of cast gold d.
It is supported on only one side
A benefit of light-cured composites over self-cured composites is: a.
That they require no mixing b.
That they have reduced porosity c.
None of the above
Polycarboxylate cements contain which acid: a.
Polycarboxylate cements contain no acid
Fluffing (aerating) alginate before using it: a.
Prevents Syneresis b.
Accelerates the set c.
Prevents imbibition d.
Compensates for settling or particulate compaction due to storage
Zinc phosphate cement helps keep a crown in place by its: a.
Ability to release fluoride b.
High chemical affinity for dentin c.
Ability to generate heat when mixed d.
Mechanical interlock between crown and tooth
An improperly carved occlusal amalgam restoration may result in: a.
Fracture of the filling or the tooth b.
Tenderness of the tooth to percussion c.
Tooth hypersensitivity to temperature changes d.
All the above
The best agent for cleaning instruments used in mixing ZOE cement is: a.
Orange solvent d.
Three ways to ensure the best results in mixing a gypsum product include: a.
Weigh the necessary gypsum b.
Measure the proper volume of water c.
Mix and vibrate for a minimum of 10min d.
Vibrate the mixed gypsum to release trapped air
Which of the following is most likely to cause delayed expansion in an amalgam restoration containing zinc? a.
Heavy condensation b.
Excess mercury in the mix c.
Overtriuration of the amalgam d.
Contamination by moisture during placement
The setting rate of an irreversible hydrocolloid may be slowed safely and effectively by: a.
Increasing the spatulation time b.
Decreasing the ratio of water to powder c.
Decreasing the temperature of the mixing water d.
Increasing the temperature of the mixing water
After a wax pattern is formed, the resulting casting will be more accurate if the pattern is: a.
Invested immediately b.
Kept in a fridge c.
Kept at room temperature d.
Any of the above answers
A force exerted to stretch a material to the point of fracture indicates its: a.
Tensile strength d.
A dental amalgam alloy contains three of the following elements: a.
Dental alloys become amalgam when mixed with a.
The volumetric weight of one cubic millimeter of water is equal to one: a.
The Brinnell and Knoop tests are used in determining: a.
An impression material should be mixed: a.
For 10sec b.
For 30sec c.
For 20sec d.
According to the manufacturer’s directions
Air incorporated into a gypsum mix results in: a.
Additional strength b.
A smoother surface c.
Surface voids and irregularities d.
None of the above
If saliva contaminates the tooth during the placement of a sealant, one should: a.
Reappoint the patient b.
Have a dentist fill the tooth c.
Check with the clinic supervisor d.
Isolate with fresh cotton products or dam, and re-etch the tooth
When gypsum begins to set, it: a.
Changes color b.
Expands slightly c.
Contracts slightly d.
Remains dimensionally stable
Alginate is also known as: a.
Polyvinyl siloxane b.
Reversible hydrocolloid c.
Irreversible hydrocolloid d.
A hydrophobic impression material
The defining characteristic of a noble metal is that: a.
It is expensive b.
It is resistant to corrosion c.
It is used to make jewelry d.
It is publicly traded as a commodity
The gypsum product which requires the most water is: a.
Die stone d.
Glutaraldehyde fumes are: a.
All the above
An interprox composite on an anterior tooth is classified by GV Black as a: a.
Class I b.
Class II c.
Class III d.
The main ingredient in a sealant material is: a.
Glass ionomer b.
Zinc phosphate c.
BIS-GMA resin d.
Pyrophosphates are added to commercial toothpaste preparations to prevent tarter accumulation. Triclosan is sometimes added as an antimicrobial agent. a.
Both statement are true b.
Both statements are false c.
Only the first statement if true d.
Only the second statement is true
An amalgam might be used to restore a lingual Class V cavity because: a.
It is unlikely to be seen b.
It is an effective restorative material c.
It is easily adapted to L pits and irregular surfaces d.
All the above
If a material is considered highly ductile, it: a.
Is likely to be quite brittle b.
May bend without breaking c.
Will return to its original shape after having been stretched d.
None of the above
The contraction of a gel due to a loss of solvent is called: a.
In the event of deep decay, which has exposed the pulp, the clinician would perform the following steps in sequence: a.
Check the occlusion b.
Place a cement base c.
Place the final restoration d.
Place a calcium hydroxide liner
The proper sequence for pouring an alginate study model is: a.
Thoroughly mix the stone and water b.
Measure the water and weigh the stone needed c.
Thoroughly vibrate the stone mix to release trapped air d.
Carefully vibrate the stone into the impression to avoid trapping air
13 A,B,C 23 A,B,D 33 B
14 D 24 D 34 D
47 C 57 D
48 A,B,D 58 C
53 A,B,C 63 B
54 C 64 D