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108 Cards in this Set
- Front
- Back
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Prior to investing a wax pattern you carve the excess wax off the wax pattern...
a. to the margin b. almost to the margin c. 2 mm shy of the margin d. doesn't matter |
b
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Trough formation of the wax pattern prior to investment has a width of:
a. 5-6 mm b. 2-3 mm c. 1-2 mm d. 0-1 mm |
c
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Wax that has been carried past the finish line may break off when the pattern is removed from die, resulting in a short or "shy" margin. This is referred to as:
a. Ripples b. Thick Margin c. Short Margin d. Over Waxed Margin |
d
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A margin not waxed completely to the indicated finsih line "red line" will not provide an adequate marginal seal. This is referred to as:
a. Ripples b. Thick Margin c. Short Margin d. Over Waxed Margin |
c
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Any roughness of the wax near the margin will be duplicated in the casting. These may not be removed during polishing and may result in plaque accumulation and lead to gingival irritation & inflammation. This is due to:
a. Ripples b. Thick Margin c. Short Margin d. Over Waxed Margin |
a
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These type of round looking margins will result in a poor seal of the restoration and poor cervical contours that can lead to periodontal problems. This is due to:
a. Ripples b. Thick Margin c. Short Margin d. Over Waxed Margin |
b
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This gypsum bonded investment material is used for castin of inlays or crowns; alloy casting shrinkage compensation is accomplished mainly by thermal expansion of the investment.
a. Type I b. Type II c. Type III |
a
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This gypsum bonded investment is also used for castin inlay sor crowns, but the major mode of compensaiton is by the hygroscopic expansion fo the investment.
a. Type I b. Type II c. Type III |
b
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This gypsum bonded investment is used in the construction of partial dentures with gold alloys.
a. Type I b. Type II c. Type III |
c
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Which type of material investment is the older type & traditionally used for conventional gold alloys.
a. Gypsum-bonded investments b. Phosphate-bonded investments c. Ethyl silica-bonded investments d. none of the above |
a
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Which type of investment material is designed primarily for alloys used in the metal ceramic restorations?
a. Gypsum-bonded investments b. Phosphate-bonded investments c. Ethyl silica-bonded investments d. none of the above |
b
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Which type of investment material is use dprincipally in teh casting of base metal alloy partial dentures?
a. Gypsum-bonded investments b. Phosphate-bonded investments c. Ethyl silica-bonded investments d. none of the above |
c
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Gypsum bonded investments are composed of:
a. Gypsum b. Silica c. Modifiers d. All of the above |
d
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The alpha hemihydrate gypsum added to gypsum bonded investments does what?
a. increases tension b. decreases ductility c. increases strength d. none of the above |
c
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The investment that remains from gypsum bonded investments may contain how much gypsum product?
a. 10-15% b. 25-45% c. 50-60% d. 80-90% |
b
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Contraction & Expansion of Gypsum bonded Investments occurs respectively:
a. From 200-400 C; approx. 700 C b. From 100-200 C; approx. 500 C c. From 400-600 C; approx. 800 C d. None of the above |
a
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In order to assure proper fit and uncontaminated castings, gypsum investments must not be heated above:
a. 800 degrees F b. 1000 degrees F c. 1200 degrees F d. 1300 degrees F |
d
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Why is Silica (SiO2) added to gypsum bonded investments?
a. To increase melting point b. To promote expansion c. To decrease contration d. To regulate thermal expansion |
d
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All of the following are true of the modifiers added to gypsum bonded investments EXCEPT:
a. Include Boric Acid & Sodium Chloride b. Regulate Thermal Expansion c. Regulate Setting Time d. Regulate Setting Expansion e. Prevent most of the shrinkage of gypsum when it is heated above 572 F |
b
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Initial and Final set of gypsum bonded investments occurs in what amount of times, respectively?
a. A few mintues; 60 minutes b. 10 minutes; 2 hours c. 20 minutes; 3 hours d. half hour; 4 hours |
a
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Smooth Wax Patterns reduce surface tension. Reduced surface tension decreases surface bubbles during investing.
a. Both statements false. b. First true, second false. c. First false, second true. d. Both statements true. |
d
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Wax sprue formers are preferred because:
a. they are least expensive b. they work predictably c. they are used at UOP d. they melt at the same rate as the pattern, thus allowing escape of the molten wax |
d
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Which is most recommended?
a. A long sprue b. A narrow diameter sprue c. A large diameter sprue d. a and b |
c
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Turbulence generated within the sprue during investing leads to:
a. porosities b. black voids c. fins d. explosions |
a
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Ring liner is used with:
a. Gypsum bonded investments b. Phosphate bonded investments c. Ethyl silica bonded investments d. All of the above |
a
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The margins of the wax pattern are oriented
a. 45 degrees to the orientation dot b. 90 degrees to the orientation dot c. 135 degrees to the orientation dot d. 180 degrees to the orientation dot |
b
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It is best to visualize the orientation dot at the ____ o'clock position and the margins at the ____ o'clock position.
a. 6 and 9 b. 3 and 6 c. 12 and 3 d. 3 and 9 |
c
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The wax pattern should be adjusted so that it is within
what range from the end of the casting ring? a. 1/2 to 1 inch b. 1/8 to 1/4 inch c. 1 to 2 inches d. 1/8 to 1/16 inche |
b - this is equivalent to about 6 mm
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Hygroscopic Expansion occurs when:
a. The investment sits in the oven b. The investment is immersed in a water bath at 100 F for one hour c. During pickling d. none of the above |
b
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Thermal contraction of the investment occurs when
a. The investment sits in the oven b. The investment is immersed in a water bath at 100 F for one hour c. The investment cools from an oven temp. of 900 F d. None of the above |
c
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The metal ceramic crown is more/less durable than an all ceramic crown and generally has inferior/superior marginal fit.
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more; superior
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True/False: A metal ceramic crown can serve as a retainer for a fixed dental prosthesis because its metal substurcture cna accomodate cast or soldered connectors.
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True
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Excessive occlusal reduction in a PFM preperation shortens the axial walls. This is a common cause of inadequate retention & resistance.
a. Both statements false b. First true, second false. c. First false, second true. d. Both statements true. |
d
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When contact in a PFM restoration is on porcelain, less/additional reduction is necessary
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additional
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A porcelain labial margin requires proper support for the porcelain; what type of shoulder is recommended?
a. Disappearing metal collar (120 degrees) b. Butt joint (90 degrees) c. 45 degree margin d. any of the above |
b
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A space should exist between the internal surface of a casting and the prepared tooth everywhere EXCEPT
a. Occlusal surface b. Internal line angles c. Proximal contacts d. Areas immediately adjacent to the margin |
d
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The ideal dimension for the luting agent space between the crown and prepped tooth is:
a. Between 20 and 40 microns per wall b. Between 20 and 40 microns total c. Between 40 and 80 microns per wall d. None of the above |
a
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Die spacer is applied to the die to increase the cement space between axial walls of the prepared tooth and the restoraton. A band of about 1mm next to the margin must be left unpainted.
a. Both statements false b. First true, second false. c. First false, second true. d. Both statements true. |
d
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When marking the margins, an ordinary lead pencil is not recommended because it can:
a. abrade the die b. its darker color can interfere with efforts to verify that the wax has been properly adapted to the margin c. tracings of the graphite can prevent complete casting of the margins d. all of the above |
d
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Which of the following is a medium-hardness was generally used with the direct technique for making patterns in the oral cavity?
a. Type I b. Type II c. Type III d. Type IV |
a
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Which of the following is a softer wax generally used for the indirect fabrication of casts?
a. Type I b. Type II c. Type III d. Type IV |
b
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True/False: to ensure that proximal contacts are not deficient, a slight amount of stone can be scraped from the adjacent tooth prior to waxing
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True
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Emergence Profile
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The tooth surface gingival to its height of contour immediately adjacent to the gingival soft tissues. It is usually flat or concave
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Most adults with Class ___ occlusion and unworn teeth have a cusp-marginal ridge occlusal scheme.
a. Class I b. Class II c. Class III d. Class II Division I |
a
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The cusp-fossa occlusal arrangement is found only when a slight Class ____ malocclusion is present.
a. Class I b. Class II c. Class III d. Class II Division I |
b
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The cusp-fossa arrangement has been recommended over the cusp-marginal ridge arrangement when occlusal reconstruction is undertaken for which of the following reasons:
a. Food impaction is prevented b. CR closure forces are nearer the LA of the teeth c. Improved stability from the tripod contacts d. All of the above |
d
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In maximum intercuspation (MI), anterior teeth ideally should be:
a. in contact b. just out of contact c. at least 1 mm out of contact d. None of the above |
b
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Centric Occlusion (CO):
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Refers to the RELATIONSHIP of the MANDIBLE TO THE MAXILLA when the teeth are in maximum occlusal contact, irrespective of the position or alignment of the condyle-disk assemblies
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What are the 5 requirements of stable occlusion?
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1. Stable stops on all the teeth when the condyles are in CR
2. Anterior Guidance is in harmony with the border movements of the Envelope of Function 3. Disclusion of all post. teeth in protrusive movements by the most anterior teeth 4. Disclusion of all the posterior teeth on the non-working/balancing side 5. Disclusion of all the post. teeth on the working side during excursions |
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True/False: in protrusive and lateral movements there is no contact on the posterior teeth
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True
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What is the exception to rule #5, which states that all the posterior teeth on the working side must disclude during excursion?
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Teeth may be in GROUP FUNCTION if they are in
precise harmony with anterior and condylar guidance. |
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The amount of contact area in a working side movement should
decrease/increase as you move posteriorly? |
decrease
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What is Ankylogossia?
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Restricted tongue
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Which is a vertical measurement and which is a horizontal measurement?
Overbite Overjet |
Overbite: Vertical
Overjet: Horizontal |
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Centric Occlusion (CO):
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Refers to the RELATIONSHIP of the MANDIBLE TO THE MAXILLA when the teeth are in maximum occlusal contact, irrespective of the position or alignment of the condyle-disk assemblies
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What are the 5 requirements of stable occlusion?
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1. Stable stops on all the teeth when the condyles are in CR
2. Anterior Guidance is in harmony with the border movements of the Envelope of Function 3. Disclusion of all post. teeth in protrusive movements by the most anterior teeth 4. Disclusion of all the posterior teeth on the non-working/balancing side 5. Disclusion of all the post. teeth on the working side during excursions |
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True/False: in protrusive and lateral movements there is no contact on the posterior teeth
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True
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What is the exception to rule #5, which states that all the posterior teeth on the working side must disclude during excursion?
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Teeth may be in GROUP FUNCTION if they are in
precise harmony with anterior and condylar guidance. |
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The amount of contact area in a working side movement should
decrease/increase as you move posteriorly? |
decrease
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What is Ankylogossia?
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Restricted tongue
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Which is a vertical measurement and which is a horizontal measurement?
Overbite Overjet |
Overbite: Vertical
Overjet: Horizontal |
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Centric Occlusion (CO):
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Refers to the RELATIONSHIP of the MANDIBLE TO THE MAXILLA when the teeth are in maximum occlusal contact, irrespective of the position or alignment of the condyle-disk assemblies
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What are the 5 requirements of stable occlusion?
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1. Stable stops on all the teeth when the condyles are in CR
2. Anterior Guidance is in harmony with the border movements of the Envelope of Function 3. Disclusion of all post. teeth in protrusive movements by the most anterior teeth 4. Disclusion of all the posterior teeth on the non-working/balancing side 5. Disclusion of all the post. teeth on the working side during excursions |
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True/False: in protrusive and lateral movements there is no contact on the posterior teeth
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True
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What is the exception to rule #5, which states that all the posterior teeth on the working side must disclude during excursion?
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Teeth may be in GROUP FUNCTION if they are in
precise harmony with anterior and condylar guidance. |
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The amount of contact area in a working side movement should
decrease/increase as you move posteriorly? |
decrease
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What is Ankylogossia?
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Restricted tongue
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Which is a vertical measurement and which is a horizontal measurement?
Overbite Overjet |
Overbite: Vertical
Overjet: Horizontal |
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All are true of Class II Malocclusion EXCEPT:
a. retrognathic jaw b. may be caused by bottle feeding or pacifier c. may lead to obstructive sleep apnea disorder d. prognathic jaw |
d
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Class III malocclusion patients exhibit:
a. an underbite b. an overbite c. prognathic jaw d. retrognathic jaw e. a and c |
e
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All are reasons why maxillary 1st bicuspids are most prone for breakdown EXCEPT:
a. First tooth that hits or guides if there is no cuspid rise b. Weak root structure c. 2 root structure d. Proximal concavity makes it a weak tooth e. maxillary bone is less dense than mandibular bone |
c
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All of the following are reasons for more breakdown around maxillary 2nd molars EXCEPT:
a. Closest tooth to TMJ fulcrum b. Receives strongest brunt of force b/c of muscle position c. Maxillary bone is less dense than mandibular bone d. three roots |
d
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Abfractions:
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Due to the stresses resulting from biomechanical loading
forces exerted on the teeth (static, as in swallowing and clenching or cyclic, as in chewing) both enamel and dentin can chip or break away. |
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Abfraction is dependent on which characteristics of force:
a. Magnitude b. Direction c. Duration d. Frequency e. Location f. All of the above |
f
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All of the following are due to tight bite EXCEPT:
a. Heavy wear facets b. Tori c. Inflammation d. Tenderness e. All of the above |
e
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What is the purpose of flux?
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Helps remove impurities
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True/False: Flux can be added to any material.
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False: Flux can only be added to conventional gold alloys
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All of the following are purposes of quenching EXCEPT:
a. Make it easier to divest b. Break down the divestment c. Increase ductility d. Strengthen the metal |
d
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Noble metals include all of the following EXCEPT:
a. Gold b. Silver c. Titanium d. Palladium e. Platinum |
c
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True/False: Silver is not considered to be a noble metal by dentists.
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True
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True/False: All noble metals are precious, but not all precious metals are noble.
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True
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All of the following are true of Base Metals EXCEPT:
a. they are non-noble b. influence physical properties c. control the amount & type of oxidation d. reduce the strength of noble metals e. strengthen noble metals |
d
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Karat
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Refers to the parts of pure gold in an alloy
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True/False: A 22 karat piece of jewelry is pure gold.
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False; Pure gold is 24 Karats; If 22 Karat, the other 2 parts are made of other metals
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Fineness:
a. Describes gold alloys by the number of parts per thousand of gold with pure gold being 1000 fine b. Has a rating ten times the percentage of gold composition c. Is considered more practical of a rating than karat d. often used to identify gold alloy solders e. All of the above |
e
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Which dental alloy is used for small inlays, can be easily burnished, and is subject to light stress?
a. Type I b. Type II c. Type III d. Type IV |
a
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Which dental alloy is used for inlays subject to moderate stress; thick 3/4 crowns, abutments, pontics, and full crowns?
a. Type I b. Type II c. Type III d. Type IV |
b
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Which dental alloy type is used for inlays subject to hard stress; thin 3/4 crowns, thin cast backings, abutments, pointics, full crown denture bases, and short span bridges?
a. Type I b. Type II c. Type III d. Type IV |
c
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Which dental alloy type is used for denture base bars and clasps, partial dneture frameworks, full crowns, and long span fixed partial denture frameworks?
a. Type I b. Type II c. Type III d. Type IV |
d
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The Olympia Gold that we use is primarily:
a. Gold and Platinum b. Gold and Palladium c. Gold and Silver d. Gold and Nickel |
b
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Nickel or cobalt based alloys, which are lighter, stronger, and less expensive, are used for what type of prosthesis (instead of Type IV dental alloys)?
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Removable Partial Denture Alloys
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Nickel and Cobalt (base metal) alloys:
a. are cheaper b. margins much harder to finish (can't burnish the metal or refine the margin) c. may cause allergies d. flex less under functional load e. all of the above |
e
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Which of the following are/is a characteristic of High Noble metals?
a. noble metal of 60% or greater b. at least 40% of noble metal composition must be gold c. noble metal content at least 25% d. noble metal content less than 25% e. a and b |
e
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Which of the following are/is a characteristic of Noble Metals?
a. noble metal of 60% or greater b. at least 40% of noble metal composition must be gold c. noble metal content at least 25% d. noble metal content less than 25% e. a and b |
c
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Which of the following are/is a characteristic of Predominantly Base Metals?
a. noble metal of 60% or greater b. at least 40% of noble metal composition must be gold c. noble metal content at least 25% d. noble metal content less than 25% e. a and b |
d
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What is the melting range of Type III (Firmilay) Gold?
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1652-1760 F (900-960 C)
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What is the melting range of Ceramo Metal (Olympia) Gold?
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2192-2336 F (1200-1280 C)
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Casting temperatures are generally 100-150 F less/greater than the melting range
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greater
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When heating an alloy with a blow torch, the trailing dot should be away from/toward the direction of the centripetal force?
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away from
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A large nodule in casting is due to:
a. breakdown of investment from excessive heat b. alloy not hot enough/insufficient casting force c. debris in wax pattern d. pattern too far from end of ring e. air trapped during divestment f. inadequate vacuum during mixing |
e
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Multiple random nodules in casting is due to:
a. breakdown of investment from excessive heat b. alloy not hot enough/insufficient casting force c. debris in wax pattern d. pattern too far from end of ring e. air trapped during divestment f. inadequate vacuum during mixing |
f
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A black or rough casting is due to:
a. breakdown of investment from excessive heat b. alloy not hot enough/insufficient casting force c. debris in wax pattern d. pattern too far from end of ring e. air trapped during divestment f. inadequate vacuum during mixing |
a
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Short rounded margins with rounded or lumpy button is due to:
a. breakdown of investment from excessive heat b. alloy not hot enough/insufficient casting force c. debris in wax pattern d. pattern too far from end of ring e. air trapped during divestment f. inadequate vacuum during mixing |
b
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Random porosity in casting is due to:
a. breakdown of investment from excessive heat b. alloy not hot enough/insufficient casting force c. debris in wax pattern d. pattern too far from end of ring e. air trapped during divestment f. inadequate vacuum during mixing |
c
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Short rounded margins with a sharp button in casting is due to:
a. dropping the ring/rapid heating of wet unhardened mold/excessive casting force b. bulky, excessively long or thin sprue or button to small c. pattern too far from end of ring/burnout if casting is too shiny d. air trapped during divestment |
c
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Fins in a casting are due to:
a. dropping the ring/rapid heating of wet unhardened mold/excessive casting force b. bulky, excessively long or thin sprue or button to small c. pattern too far from end of ring/burnout if casting is too shiny d. air trapped during divestment |
a
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Shrink-spot/Suck-back porosity in the casting is due to:
a. dropping the ring/rapid heating of wet unhardened mold/excessive casting force b. bulky, excessively long or thin sprue or button to small c. pattern too far from end of ring/burnout if casting is too shiny d. air trapped during divestment |
b
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Presence of nodules only on the underside of a casting is due to:
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Prolonged vibration after pouring
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