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99 Cards in this Set
- Front
- Back
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The working cast, used to fabricate the die for FPD, is equivalent to:
A. diagnostic cast B. master cast C. copy of diagnostic cast D. None of the above |
B. master cast
(1st cast made with prepped teeth) |
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Cuts for removable dies on working casts should be made with _____ walls
A. convergent B. divergent C. parallel |
C. parallel
(if not parallel, make divergent, so die can be removed) |
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Overtrimming of removable dies leads to:
A. undercontoured restorations B. overcontoured restorations |
B. overcontoured restorations
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What is the most common error to axial contour of FPDs?
A. excessive convexity B. excessive concavity C. reduced convexity D. reduced concavity |
A. excessive convexity
(overcontoured) |
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The height of contour of a mandibular molar extends horizontally about ___ on the facial, and ___ on the lingual, beyond the plane of the root.
(select all) A. 0.5 mm B. 1.0 mm C. 1.5 mm D. 2.0 mm |
A. 0.5 mm (Facial)
B. 1.0 mm (Lingual) |
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T/F
From the base of the sulcus to the height of contour, the emergence profile is straight |
True
(straight in the gingival 1/3) |
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T/F
When taking an interocclusal record, for fabrication of FPD, the recording material must NOT extend to adjacent unprepared teeth |
True
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T/F
If you can hand articulate casts (and they're stable), an interocclual record is not needed |
True
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What are the determinants of occlusal morphology of ANTERIOR teeth?
A. inclination of articluar eminence B. overjet C. overbite D. medial wall of glenoid fossa E. intercondylar distance |
B. overjet
C. overbite |
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What are the determinants of occlusal morphology of POSTERIOR teeth?
(select all) A. inclination of articluar eminence B. overjet C. overbite D. medial wall of glenoid fossa E. intercondylar distance |
A. inclination of articluar eminence
D. medial wall of glenoid fossa E. intercondylar distance |
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If no canines are touching (missing, prepped, etc.) fabricate the _____ teeth first.
A. upper B. lower |
B. lower
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Match the condylar movements to it's respective wall contact, when fabricating the custom guide table.
- top - medial - back A. balancing B. working C. protrusive |
A. balancing = top & medial
B. working = top & back C protrusive = top |
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T/F
When making a 3 unit PFM (such as 2-4), make the preparation along the long axis of the individual teeth |
False
(won't be parallel = difficult path of draw) (adjust each tooth so that the mesial wall of mesial tooth is parallel to the distal surface of the distal tooth) |
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What is the OPTIMUM crown-root ratio for an FPD abutment?
A. 1:1 B. 2:3 C. 1:2 D. 1:4 |
B. 2:3
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What is the MINIMUM crown-root ratio for an FPD abutment?
A. 1:1 B. 2:3 C. 1:2 D. 1:4 |
B. 1:1
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Rank the following teeth in order of best abutment to worst abutment.
- lateral incisor - canine - premolar - molar |
1) molar
2) canine (long root) 3) premolar 4) lateral incisor |
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Which of the following FPD placements is unwise?
A. 1st molar pontic between 2nd molar and 2nd premolar B. 1st Molar & 2nd premolar pontic between 2nd molar and 2nd premolar C. 1st molar and 1st & 2nd premolar pontic between canine & 2nd molar abutments |
C. 1st molar and 1st & 2nd premolar pontic between canine & 2nd molar abutments
Pontics - 1st premolar = 1 root - 2nd premolar = 1 root - 1st molar = 2 roots - total = 4 roots Abutments - canine = 1 root - 2nd molar = 2 roots - total = 3 roots pontic roots (4) > abutment roots (3) = unwise design |
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The deflection of an FPD is equal to:
(select all) A. length³ B. length² C. 1/thickness³ D. 1/thickness² |
A. length³
C. 1/thickness³ |
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T/F
When using double abutments, you add the total abutment roots & compare to pontic roots to determine if FPD design is acceptable |
False
(Only count 2° abutments) ex. canine, premolar, 2nd molar, 3rd molar (w/ 1 root) as abutment teeth. Premolar & 1st molar as pontic. Pontic = 3 roots Total abutment = 5 roots 2º abutments = 2 roots pontic (3) > 2º abutment (2) = unfavorable design |
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For a pier abutment, where is a nonrigid connector placed?
A. anterior pontic B. middle abutment C. posterior pontic D. distal abutment |
B. middle abutment
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For a pier abutment with a nonrigid connector, where is the KEYWAY placed?
A. mesial of pontic B. distal of pier abutment |
B. distal of pier abutment
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For a pier abutment with a nonrigid connector, where is the KEY placed?
A. mesial of pontic B. distal of pier abutment |
A. mesial of pontic
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Cantilever FPD's may only be placed for replacing:
(select all) A. lateral incisor B. canine C. premolar D. molar |
A. lateral incisor (canine as single abutment)
B. premolar (double abutments) |
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For maxiallry molars, where on the tooth are the following furcations found?
- mesial - distal - buccal (ex. straight mesial, more buccal, etc.) |
Mesial = more lingual
Distal = straight distal Buccal = straight buccal |
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For a PFM, what are the corresponding thicknesses for:
- cast metal - porcelain - entire PFM |
- Cast metal = 0.2-0.3 mm
- Porcelain = 1.2 mm - Entire PFM = 1.5 mm |
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T/F
Porcelain has both high compression & tensile strength |
False
- Porcelain = high compression strength - Metal = high tensile strength |
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At the porcelain-metal interface, the porcelain should be at least ____ thick
A. 0.5 mm B. 1.0 mm C. 1.2 mm D. 1.5 mm |
A. 0.5 mm
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Centric contacts can be located on either porcelain or metal of a metal-ceramic restoration. However, they must be at least 0.5 mm away from the porcelain-metal junction
A. The 1st statement is true, the 2nd statement is false B. The 1st statement is false, the 2nd statement is true C. Both statements are true D. Both statements are false |
A. The 1st statement is true, the 2nd statement is false
(must be 1.5 mm away) |
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T/F
The larger the gauge, the smaller the diameter of the sprue |
True
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T/F
During metal framework adjustment, multidirectional grinding is preferred. |
False
(grind in 1 direction) (multidirectional can trap debris) |
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Setting & hygroscopic expansion of investment cast is __, thermal expansion is ___ when the W/P ratio is increased
A. increased B. decreased C. not effected |
A. decreased (setting & hygroscopic expansion)
A. decreased (thermal expansion) |
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T/F
Spatulation has no effect on setting & hygroscopic expansion |
False
(↑ time & rate INCREASES expansion) (no effect on thermal expansion) |
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Adding _____ to wax can increase the melting range and hardness of dental waxes
A. beeswax B. paraffin C. carnauba D. gum arabic |
C. carnauba
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Which dental wax has the smallest % of thermal expansion?
A. beeswax B. paraffin C. carnauba D. gum arabic |
C. carnauba
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Which class of dental waxes has a tendency to warp or distort on standing?
A. pattern B. processing C. impression |
A. pattern
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Match the light source to it's wavelength color
- yellow - blue - white (natural) A. fluorescent B. northern daylight C. incandescent |
A. fluorescent = blue
B. northern daylight = white (natural) C. incandescent = yellow |
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What is the difference between scattering & diffused reflection?
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Scattering = light penetrates object, not absorbed, returns to surface, and scatters
Diffused Reflection = light DOES NOT penetrate object, and is reflected in multiple directions |
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Relates to a specific wavelength band of light, indicating colors (red, yellow, green)
A. hue B. value C. chroma |
A. hue
tells that a tooth is yellow, but not how much yellow |
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Describes the lightness of a color (white – black)
A. hue B. value C. chroma |
B. value
tells that a tooth is a dark yellow or a bright yellow |
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Describes the saturation, or concentration of a color
A. hue B. value C. chroma |
C. chroma
(concentration of hue) tells how much yellow is in the tooth |
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Using the CIE L*a*b* Color system, the L* axis describes:
A. lightness B. red to green C. yellow to blue |
A. lightness
0 = black 100 = white |
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Using the CIE L*a*b* Color system, the a* axis describes:
A. lightness B. red to green C. yellow to blue |
B. red to green
+a* = red -a* = green |
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Using the CIE L*a*b* Color system, the b* axis describes:
A. lightness B. red to green C. yellow to blue |
C. yellow to blue
+b* = yellow -b* = blue |
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For the Classical Vita Shade Guide match the label to it's shade.
- A1-A4 - B1-B4 - C1-C4 - D1-D4 A. grayish B. reddish-yellow C. reddish-gray D. reddish-brown |
- A1-A4 = reddish-brown
- B1-B4 = reddish-yellow - C1-C4 = grayish - D1-D4 = reddish-gray |
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T/F
Shade selection should be made before any intraoral procedure |
True
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What is the order of proper shade matching procedure?
- hue - value - chroma |
1) value
(start with darkest move to lightest) 2) chroma (select top 3 of selected value) 3) hue (determine if tooth is more yellow or red) |
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In shade matching guides the letter (A, B, C, D) refers to the:
A. hue B. value C. chroma |
A. hue
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In shade matching guides (A1, A2, etc.) the number refers to the:
A. hue B. value C. chroma |
C. chroma
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What establishes the porcelain-metal bond?
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Metal-oxidizing (degassing)
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Which of the following will cause porcelain fracture at the porcelain-metal interface?
(select all) A. poor metal framework design B. degassing of metal C. contamination of metal after opaque application D. fusing opaque coat of porcelain at too LOW of a temperature |
A. poor metal framework design
D. fusing opaque coat of porcelain at too LOW of a temperature (degassing at too LOW of a temperature) (contaminated metal BEFORE opaque application) |
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A majority of porcelain is composed by:
A. kaolin B. feldspar C. quartz D. leucite |
B. feldspar
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What is frit? (involved in the porcelain process)
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- Porcelain materials are heated until glassy, then rapidly cooled by quenching in water
- The glassy mass fractures into small fragments. - These fragments are called frit. - frit is then milled until at desired particle size for dental porcelain |
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The amount of ____ controls the thermal coefficient of expansion & contributes strength to the porcelain
A. kaolin B. feldspar C. quartz D. leucite |
D. leucite
(comes from feldspar) |
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Contributes to stability of porcelain during heating
A. kaolin B. feldspar C. quartz D. leucite |
C. quartz
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Gives porcelain it's opaqueness
A. kaolin B. feldspar C. quartz D. leucite |
A. kaolin
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Adds to the vitality of a restoration & minimizes the metameric effect between teeth & restorative materials
A. fluorescence B. opalescence C. opaqueness D. value |
A. fluorescence
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The ability of a translucent material to appear blue in reflected light & orange-yellow in transmitted light
A. fluorescence B. opalescence C. opaqueness D. value |
B. opalescence
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The primary source of color of a PFM comes from:
A. dentin porcelain B. enamel porcelain C. opaque porcelain D. glazing |
C. opaque porcelain
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For a partial veneer crown (3/4 crown prep) axial reduction is prepared on:
A. 1 wall B. 2 walls C. 3 walls D. 4 walls |
C. 3 walls
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For a partial veneer crown (3/4 crown prep) occlusal reduction is prepared with:
A. 1.5 mm on centric cusp, 1.5 mm on noncentric cusp B. 1.0 mm on centric cusp, 1.0 mm on noncentric cusp C. 1.5 mm on centric cusp, 1.0 mm on noncentric cusp D. 1.0 mm on centric cusp, 1.5 mm on noncentric cusp |
C. 1.5 mm on centric cusp, 1.0 mm on noncentric cusp
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For a partial veneer crown (3/4 crown prep) retention grooves should be:
A. parallel in BL direction and convergent in MD direction B. convergent in BL direction and parallel in MD direction C. convergent in BL direction and convergent in MD direction D. parallel in BL direction and parallel in MD direction |
A. parallel in BL direction and convergent in MD direction
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For a partial veneer crown (3/4 crown prep) the proximal groove should have ____ on the buccal wall, and ______ on the lingual wall
A. 90º angle B. flare |
B. flare (buccal)
A. 90º angle (lingual) |
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A resin bonded FPD is indicated to replace:
(select all) A. maxillary incisor B. mandibular incisor C. maxillary bicuspid D. mandibular bicuspid |
A. maxillary incisor
B. mandibular incisor D. mandibular bicuspid |
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What is the difference between a Rochete resin bonded FPD and a Maryland Bridge?
- perforations - etched base of metal retainers |
- Rochette = perforations of metal retainers
- Maryland = etched base of metal retainers |
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T/F
A provisional restoration is usually not needed for a resin bonded FPD |
True
(prepared in enamel) |
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Attachments machined in metal alloys which are more accurate and provide less wear
A. precision B. semi-precision |
A. precision
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Attachments fabricated by direct casting of plastic, wax, or patterns, and can be cast in a wide choice of alloys
A. precision B. semi-precision |
B. semi-precision
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When casting conventional gold alloys, which type of investment material is used?
(select all) A. Silica-bonded investments B. Phosphate-bonded investments C. Calcium Sulfate- bonded investments |
C. Calcium Sulfate- bonded investments (Gypsum)
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When casting high-melting-point alloys, which type of investment material is used?
(select all) A. Silica-bonded investments B. Phosphate-bonded investments C. Calcium Sulfate- bonded investments |
A. Silica-bonded investments
B. Phosphate-bonded investments |
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If a mold that is created for investing and casting does not ______ to compensate for the action of the metal alloy, the casting will not fit.
A. Equate B. Contract C. Expand D. None of the above |
C. Expand
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In metal-ceramic restorations, failure or fracture usually occurs:
A. In the porcelain B. At the porcelain-metal interface C. In the metal |
B. At the porcelain-metal interface
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Teeth that appear to be color matched under one type of light may appear very different under another light source. This is called:
A. Fluorescence B. Metamerism C. Opaqueness D. Translucency |
B. Metamerism
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Glazed porcelain is:
A. Obtained by heating the previously fired body very slowly for 60 minutes at its fusing temperature B. Nonporous, resist abrasion, possesses esthetic ability and is well tolerated by the gingiva C. Not as durable as an over-glazed porcelain D. All of the above |
B. Nonporous, resist abrasion, possesses esthetic ability and is well tolerated by the gingiva
(over-glazed porcelain wears more rapidly) |
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Which statement is true regarding color matching of a metal ceramic crown?
A. Color matching should be done under two or more different light sources B. Metamerism is important in matching the shade C. Staining of the porcelain will increase metameric responses D. All of the above |
D. All of the above
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Which statement is true regarding fluorescence:
A. Fluorescence is the optical property by which a material reflects ultraviolet radiation B. Human teeth fluoresce mainly blue-white hues, 400-450 nm range C. Fluorescence makes a definite contribution to brightness & vitality of natural teeth D. All of the above |
D. All of the above
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Color can be described in terms of tree standard components. Which of the following is not used to describe a color?
A. Hue B. Chroma C. Value D. Intensity |
D. Intensity
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Which of the following is the single most important factor in shade selection?
A. Hue B. Chroma C. Value D. Translucency |
C. Value
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Which of the following are indications for fixed bridgework when contemplating the fabrication of fixed bridge for a patient?
A. Edentulous areas which would not otherwise be more satisfactory restored with a RPD B. To prevent the over-eruption of opposing teeth and the drift of teeth neighboring the edentulous space C. Suitable abutment teeth with favorable crown/root ratio D. esthetics E. Clinical and technical ability of the dentist F. All of the above |
F. All of the above
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Which of the following are contraindications for fixed bridgework
A. Poor oral hygiene B. High caries rate C. Teeth likely to be lost in the near future D. Spaces not detrimental to the maintenance of arch stability or dental health E. Unacceptable occlusion F. All of the above |
F. All of the above
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The shade of the ceramic crown should be matched by what order of color characteristics?
A. hue, chroma, value B. chroma, hue, value C. chroma, value, hue D. Value, hue, chroma, E. Value, chroma, hue |
E. Value, chroma, hue
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A non-rigid connector is comprised of:
A. A key B. A keyway C. A key and a keyway |
C. A key and a keyway
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A non-rigid connector is:
A. A broken-stress mechanical union of retainer and pontic B. Used instead of the rigid solder joint in “special cases” C. Consists of T-shaped key that is attached to the pontic D. Consists of a dovetail keyway placed within the retainer E. All of the above |
E. All of the above
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Which of the following is important factor during evaluation of a prospective abutment tooth for a FPD?
A. Crown-to-root ratio B. Root configuration C. Number of roots D. Root surface area E. All of the above |
E. All of the above
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Which of the following are important factors in fixed bridgework design?
A. Root configuration B. Crown-to-root ratio C. Axial alignment of teeth D. Length of the lever arm (span) E. All of the above |
E. All of the above
- Root configuration (wide > round) - Crown-to-root ratio (2:3 = optimal) - Axial alignment of teeth (not tilted = good) - Span (D = length³) |
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The path of insertion for an anterior 3⁄4 crown should be:
A. Perpendicular to the incisal one-half of the labial surface rather than the long axis of the tooth B. Parallel to the incisal one-half to two-thirds of the labial surface rather than the long axis of the tooth C. Parallel to the long axis of the tooth D. Parallel to the cervical one-third of the labial durface rather than the long axis of the tooth |
C. Parallel to the long axis of the tooth
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All of the following statements regarding metal-ceramic restorations are true EXCEPT:
A. The metal and porcelain must have compatible melting temperatures as well as compatible coefficient of thermal expansion B. The metal’s melting temperature should be at least 200-500ºF higher than the fusing temperature of the porcelain C. The metal coping should preferably have sharp surfaces to prevent shrinkage of the porcelain D. The absolute minimum required thickness of the porcelain is 0.7 mm and the metal’s thickness may vary from 0.3-0.5 mm for noble alloys and 0.2 mm for base metal alloys E. In function, glazed porcelain on the occlusal surface removes 40 times as much of the opposing tooth structure than gold |
A. The metal and porcelain must have compatible melting temperatures as well as compatible coefficient of thermal expansion
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In investments, what is the Refractory material?
A. silicon dioxide B. α-calcium sulfate hemihydrate C. phosphate, ethyl silicate |
A. silicon dioxide
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In investments, what is the binder material for gold alloys?
A. silicon dioxide B. α-calcium sulfate hemihydrate C. phosphate, ethyl silicate |
B. α-calcium sulfate hemihydrate
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In investments, what is the binder material for palladium or base metal alloys?
A. silicon dioxide B. α-calcium sulfate hemihydrate C. phosphate, ethyl silicate |
C. phosphate, ethyl silicate
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What is the best way to minimize residual stresses in wax patterns?
A. leave standing at room temperature B. Increase temperature of wax at the time the pattern is adapted and shaped C. Decrease temperature of wax at the time the pattern is adapted and shaped |
B. Increase temperature of wax at the time the pattern is adapted and shaped
(less tendency for distortion) (can also store at low temperature) |
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If a restoration is placed on ENAMEL, the restoration should have a __ emergence angle
A. + B. – C. 0 |
C. 0
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If a restoration is placed APICAL to the CEJ, the restoration should have a __ emergence angle
A. + B. – C. 0 |
A. +
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If a restoration is placed on ON ROOT, and the restoration HAS a CEJ, the restoration should have a __ emergence angle
A. + B. – C. 0 |
C. 0
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If a restoration is placed on ON the ROOT, and the restoration has NO CEJ, the restoration should have a __ emergence angle
A. + B. – C. 0 |
A. +
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If a restoration is placed with FURCATION, the restoration should have a __ emergence angle
A. + B. – C. 0 |
B. –
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Regarding the sprue, during the lost-wax technique, it is better to have a ____ diameter, and a ____ length
A. large B. small C. long D. short |
A. large diameter (improves flow)
D. short length (overcome porosity) (larger gauge = smaller diameter) |
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What is the reason for the liner inside the casting ring?
A. decreases amount of expansion of investment material B. allows for more expansion of investment material |
B. allows for more expansion of investment material
(expansion of investment compensates for shrinkage of metal) |
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T/F
If the patient thinks the PFM crown is too dark upon delivery, the value can easily be increased. |
False
- difficult to increase value - adding white causes porcelain to become opaque - surface texture can increase the reflectance = ↑ value |
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What is the purpose of vacuum firing of porcelain?
A. remove impurities B. decrease internal voids C. strengthens porcelain D. improves value |
B. decrease internal voids
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