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Flashcards in Operative1 Deck (109):
1

All Class Ill lesions should be filled with composite resin, because they are esthetically important.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

neither the statement nor the reason is correct (Composite resin is not recommended for Class III lesions on the distal-lingual aspect of canines (use either amalgam or direct gold))

2

When two teeth adjacent to each other have Class III lesions, you should prepare ? first and fill ? first

• the larger one
• the smaller one

3

The ideal amount of dentin required between an amalgam restoration and the pulp for insulation is:
• 0.5 mm
• 1.0 mm
• 2.0 mm
• 3.0 mm

2.0 mm (1.0 - 1.5 mm is acceptable but not ideal)
Amalgam is a poor thermal insulator; this is why a base of either calcium hydroxide or zinc oxide-eugenol is placed under most amalgam restorations (to provide thermal protection).

4

patient comes in claiming that their holistic doctor told him that he has an allergy to mercury and needs only white fillings. Your best response is:
• there is no such thing as a mercury allergy; plus, there is no mercury in amalgam fillings
• you might have mercury allergy, but that is very rare; plus, there is no mercury in amalgam fillings
• there is no such thing as a mercury allergy; plus, with proper isolation and technique, your exposure will be minimal
• you might have a mercury allergy, but that is very rare; plus, with proper isolation and technique, your exposure will be minimal

you might have a mercury allergy, but that is very rare; plus, with proper isolation and technique, your exposure will be minimal

5

The amount of mercury remaining in dental amalgam after condensation directly affects:

(1) the porosity of the restoration,
(2) the compressive strength of the restoration,
(3) the corrosive resistance of the restoration,
(4) the surface finish of the restoration

6

Which of the following are similarities between amalgam Class II restorations and inlay Class II restorations? Select all that apply.
• occlusal isthmus width
• depth into dentin
• convergent walls on the occlusal surface
• axiopulpal line angle shape
• gingival wall form
• internal line angles

• occlusal isthmus width
• depth into dentin
• axiopulpal line angle shape

7

You would prefer your assistant overtriturate the amalgam rather than undertriturate it. This is because an overtriturated amalgam will still have optimal strength.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

both statements are true

8

A properly triturated amalgam appears ?

shiny, wet, smooth, and homogeneous (The longer the trituration time, the smaller the setting expansion) (Remember: An overtriturated mix is preferable to an undertriturated mix)

9

If an amalgam "chips" when you are carving it, the reason for this is that the amalgam ?

was condensed after its working time had elapsed

10

Class V amalgam restorations rarely require retentive grooves, but if they are used, they are placed at the incisoaxial and gingivoaxial line angles.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

the first statement is false, the second is true

11

The nonparallel mesial and distal walls of the class V preparation are ? to the transitional line angles

straight and parallel (The outline form for the classical Class V amalgam preparation is a deformed trapezoid (sometimes called "kidney-shaped'). The outline form is determined by the location and size of the carious area)

12

The occlusal and gingival walls of the Cl V preparation should be gently curved arcs as determined by ?. Note: These arcs should be as parallel to each other as possible

the contour of the free margin of the gingival tissue

13

If moisture is incorporated into an alloy that contains zinc, the water reacts with the zinc to produce hydrogen gas. The resulting pressure from the liberated gas produces severe expansion of the amalgam. This results in the following clinical manifestations:

• The amalgam protrudes from the cavity preparation
• Postoperative pain
• Excessive corrosion

14

The most important problem for amalgam restorations is that they have ?

different coefficients of thermal expansion/contraction

15

Delayed expansion of amalgam restorations is associated with which two factors?
• insufficient trituration and condensation
• high residual mercury
• the contamination of the amalgam by moisture during trituration and condensation
• the failure to use a cavity varnish

• insufficient trituration and condensation
• the contamination of the amalgam by moisture during trituration and condensation (this one is the principal cause of failures)

16

The tensile strength of amalgam is about ? of its compressive strength,

one-fifth to one-eighth

17

Amalgam is brittle and has a ? edge strength

low

18

Amalgam is a ? thermal conductor and a ? thermal insulator.

• high
• poor

19

High-copper amalgams exhibit ? clinically relevant creep or flow

no

20

You need a minimum thickness of ? mm (in axial areas) to 1.5 to 2 mm (in areas of occlusal contact) of Amalgam for adequate compressive strength

0.75

21

Proper condensation and carving makes an amalgam restoration stronger because it removes the mercury-rich matrix.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct and related

22

The most important consideration in the strength of the amalgam is the mercury content. If the mercury content exceeds ? a dramatic loss in strength results

55% (amalgam must contains less than 50% mercury)

23

Which phase of the amalgam reaction is prone to corrosion in clinical restorations?
• gamma
• gamma-one
• gamma-two
• gamma-three

gamma-two (the gamma-two phase is not present in the high-copper amalgams [Copper contents over 6%])

24

Amalgam has a coefficient of thermal expansion approximately ? that of tooth structure.

twice

25

When preparing a Class II amalgam restoration, all surface angles should be approximately 90 degrees.
However, the internal angles should be rounded.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

both statements are true
90° angle = butt joint

26

Class II amalgam preps have ? retention and resistance form for both the proximal box and occlusal portion of the preparation

independent

27

When the facial (or lingual) extension is ? from the primary groove toward the cusp tip, reduction of the cusp(s) for amalgam capping is mandatory

two-thirds

28

When the facial (or lingual) extension is ? from the primary groove toward the cusp tip, reduction of the cusp(s) for amalgam capping is mandatory for the development of adequate resistance form. Note: The final restoration has to have restored cusps with a minimal thickness of ? of amalgam for functional cusps and ? of amalgam for nonfunctional cusps.

• two-thirds
• 2 mm
• 1.5 mm

29

Beveling the gingival cavosurface margin of the proximal box of a Class II amalgam preparation on a permanent tooth:
• should result in a long bevel
• is contraindicated because of the low edge strength of amalgam
• should remove unsupported enamel that may fracture
• is unnecessary since the tooth structure in this area is strong

should remove unsupported enamel that may fracture (The gingival cavosurface margin is beveled only if it is in the enamel. Beveling is not necessary if the gingival margin is within cementum)

30

Which tooth requires special attention when preparing the occlusal aspect for a restoration?
• mandibular first bicuspid
• mandibular second bicuspid
• maxillary first molar
• maxillary first bicuspid

mandibular first bicuspid (The bur should be tilted lingually to prevent encroachment on the facial pulp horn and also to maintain dentinal support of the lingual cusp)

31

All four walls of a Class I amalgam preparation should diverge slightly because divergence prevents undermining of the marginal ridges.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

the statement is not correct, but the reason is correct (Only two walls of a Class I amalgam preparation should diverge, the mesial and distal. The buccal and lingual walls of a Class I amalgam preparation should be convergent)

32

For premolars, the distance from the margin of the mesial and distal wall to the proximal surface must not be less than ?. For molars this minimal distance is ?.

• 1.6 mm
• 2 mm

33

The matrix band should be removed after condensation of the amalgam but prior to the final carving of the restoration. This is because the wedge compensates for the thickness of the matrix band
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct but not related (the true reason for carving after the removal of the band is to gain proper access to all margins of the amalgam restoration)

34

The matrix band should be ? into contact with adjacent teeth, this will help ensure contact.

burnished

35

• Postoperative sensitivity of amalgam may be caused by ?
• Marginal voids may be caused by ?

• inadequate condensation, or lack of proper dentinal sealing
• inadequate condensation, or amalgam breaking away from margins when carving

36

The diagonal slot opening on the Tofflemire matrix retainer (also called the Universal matrix system) is always placed facing the gingiva. This:
• permits easy separation of the retainer from the band in an occlusal direction
• allows for better contour of band to tooth
• allows for easier wedge placement
• is less harmful on the gingiva

permits easy separation of the retainer from the band in an occlusal direction (In addition, the larger circumference of the matrix band is always placed toward the occlusal surface of the tooth. This accommodates for the larger tooth circumference at the contact level)

37

The primary function of the matrix band is ?. Other functions include providing a rigid wall to condense filling material against, preventing excess filling material from going subgingivally, and to some extent, limiting moisture contamination during condensation.

• to restore anatomical contours and contact areas

38

When placing a matrix band for a Class II amalgam restoration, the gingivoocclusal width of the band should be trimmed to be ?

at least 1 mm greater than the expected marginal ridge height

39

Which of the following are true statements regarding the polishing of amalgam? Select all that apply.
• it reduces marginal discrepancy
• it should be done about 10 minutes after placement
• occlusion should not be checked prior to polishing
• it prevents tarnishing of the restoration
• it improves the appearance of the restoration
• it should be done with a dry polishing powder

• it reduces marginal discrepancy
• it prevents tarnishing of the restoration
• it improves the appearance of the restoration
The final finish of the amalgam restoration should not be done until after the amalgam is fully set. It should be delayed for at least 24 hours after condensation and preferably longer (24-48 hours)

40

Heat generation during polishing of amalgam must ?. The use of dry polishing powders and discs can easily raise the surface temperature above the 60°C (140°F) danger point. Thus, a wet abrasive powder in a paste form is the agent of choice. Note: Heat will not only damage the pulp but also draws mercury to the surface of the restoration and ? will result

• be avoided
• an inferior restoration

41

Final polishing of amalgam may be accomplished using ?

a rubber cup with flour of pumice followed by a high-luster agent, such as tin oxide

42

All of the following are true concerning a Class V amalgam preparation EXCEPT one. Which one is the EXCEPTION?
• the outline form is determined primarily by the location of the free gingival margin
• the mesial, distal, gingival, and incisal walls of the cavity preparation diverge outward
• the retention form is provided by the gingival retention groove along the gingivoaxial line angle and an incisal retention groove along the incisoaxial line angle
• a cervical clamp is usually necessary to retract gingival tissues

the outline form is determined primarily by the location of the free gingival margin (outline form is determined primarily by the location and size of the carious lesion.)

43

Which of the following statements in reference to amalgam is false?
• increased trituration time will increase compressive strength and decrease setting expansion
• a decrease in particle size will decrease compressive strength and increase setting expansion
• increased condensation pressure will increase compressive strength and decrease setting expansion

a decrease in particle size will decrease compressive strength and increase setting expansion (The smaller the particle size, the less the expansion)

44

Amalgam restorations require an obtuse cavosurface margin because amalgam is a brittle material.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

the statement is not correct, but the reason is correct (Amalgam restorations require a 90° cavosurface margin)

45

New amalgam alloys are termed "high copper"
The higher percentage of copper reduces marginal breakdown.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

both statements are true

46

Which of the following statements are true regarding creep? Select all that apply.
• creep is a process that happens over time
• creep gradually increases the marginal integrity of an amalgam restoration
• undertrituration tends to increase the creep rate
• overtrituration tends to decrease the creep rate
• increasing the condensation pressure decreases the creep rate

• creep is a process that happens over time
• undertrituration (also overtrituration ) tends to increase the creep rate
• increasing the condensation pressure decreases the creep rate

47

creep has been implicated as ?

one of the main causes for marginal fracture of amalgam restorations

48

? are helpful in reducing marginal leakage around amalgam restorations.

Corrosion products (such as tin oxide and tin sulfide)

49

There is no free mercury in triturated amalgam because trituration causes the alloy to dissolve in the mercury.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

the statement is correct, but the reason is not (There is no free mercury in triturated amalgam because trituration coats the alloy particles with mercury)

50

What distinguishes a base from a cement from a cavity liner?
• final application thickness
• degree of pulpal protection
• biocompatibility of material
• degree of hardness

final application thickness

51

The most important consideration for pulp protection in restorative techniques is ?

the thickness of the remaining dentin

52

In general, cements that are thicker than ? are termed bases and, as such, function to ?

• 2 mm
• replace lost dentin structure beneath restorations.

53

• Cements for luting have a desired final film thickness of ?
• Cavity liners have a desired final film thickness of ?
• Bases have a final application thickness of ?

• approximately 15 to 25 microns
• approximately 5 microns
• approximately 1 mm to 2 mm

54

Although cavity liners provide ?, they are not used for ?

• a barrier to chemical irritants
• thermal insulation or to add bulk to a cavity preparation

55

Bases act as ?

• a barrier against chemical irritation,
• provide thermal insulation,
• can resist the condensation forces on a tooth when placing a restoration.

56

Which of the following statements are true regarding glass inomer cements? Select all that apply.
• release fluoride
• good chemical adhesion
• good thermal insulator
• thermal expansion similar to tooth
• high solubility after initial setting

• release fluoride
• good chemical adhesion
• good thermal insulator
• thermal expansion similar to tooth
lower solubility than zinc phosphates (which are lower than zinc polycarboxylates).

57

Glass ionomer cements are hybrids of ?

silicate and polycarboxylate cements

58

Important: ? by ionized polyacrylic acid side-groups is the principal mechanism of chemical adhesion to tooth structure.

Chelation of calcium ions on tooth structure

59

Glass ionomer cements generally contain fluoro-alumino-silica powder.
The fluoro-alumino-silica is the portion responsible for one of the major advantages of glass ionomer.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

both statements are true (powder is a fluoro-alumino-silicate glass that reacts with a liquid, which is polyacrylic acid)

60

Zinc phosphate cement is mixed using the technique, which greatly extends the working time (by as much as 300%)

"frozen slab"

61

Zinc polycarboxylate cement: advantages:

chemically bonds to tooth structure (via chelation reaction between the carboxyl groups of the cement and calcium in the tooth structure)

62

Zinc polycarboxylate cement: disadvantages:

more viscous when mixed and has a shorter working time than does zinc phosphate cement.

63

Resin-modified glass ionomer luting agents: have properties similar to glass ionomer cements, but have ?

higher strength and lower solubility

64

Resin-modified glass ionomer luting agents should not be used with ?

all-ceramic restorations dues to reports of ceramic fracture, most likely the result of expansion from water absorption

65

Resin luting agents disadvantages:

irritating effects on the pulp, high film thickness (> 25 mm)

66

As a general rule, ? are the best choice for luting ceramic restorations

resin cements

67

ZOE cements make good temporary sedative restorations because their pH is very basic.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

the statement is correct, but the reason is not (their pH is about 7 (neutral))

68

? is fine for basing large and complex cavities. This material is able to withstand the pressure of amalgam condensation and it has minimal effect on the pulp.

Reinforced ZOE (zinc oxide and finely divided polymer particles (polymethyl methacrylate) in the amount of 20% to 40% by weight)

69

Contraindications to the use of ZOE include:

1. On dentin or enamel prior to bonding: compromises bonding.
2. As a base or liner for composite resins: eugenol interferes with polymerization.
3. Patients who are allergic to eugenol (or oil of cloves): this is somewhat common.
4. Direct pulp capping: eugenol is a pulpal irritant when in direct pulpal contact. (Eugenol has a palliative effect on the dental pulp, and this is one of the main advantages of using this type of cement)

70

IRM (Intermediate Restorative Material) will interfere with subsequent placement of a resin filling. This is because IRM is a form of zinc oxide-eugenol.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct and related

71

IRM (Intermediate Restorative Material) uses:

Uses:
• As an intermediate restorative material for both Class I and II restorations.
• As a base under nonresin restorations
• Restoration of deciduous teeth (when permanent teeth are 2 years or less from eruption)
• Restorative emergencies

72

Zinc phosphate cement can cause irreversible pulpal damage because it shrinks slightly on setting.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct but not related (The initial mixture of this cement is very acidic (pH of 3.5) and can cause irreversible pulpal damage if a cavity varnish (2 coats) is not placed on the tooth prior to cementation of the crown)

73

Zinc phosphate cements shrink more when ?

they are in contact with air; thus, the cement should not be allowed to dry out

74

Zinc phosphate cement powder and liquid?

powder: mostly zinc oxide
liquid: orthophosphoric acid

75

Zinc phosphate cement has superior strength compared to other cements, and its retention depends on ? (as opposed to glass ionomer and polycarboxylate cements which adhere to tooth structure by virtue of the polyacrylic acid in the liquid).

mechanical interlocking

76

Zinc phosphate cement liquid that has lost some of its water content will cause the setting time of the mix to be ?

prolonged

77

Mixing zinc phosphate cement very rapidly will ? the final compressive strength of the cement

decrease

78

Zinc phosphate cements should be mixed on a cool glass slab, adding a small amount of powder to the liquid every 20 seconds. This is done to gain which of the following advantages. Select all that apply.
• stronger final set
• lower solubility
• greater viscosity

• stronger final set
• lower solubility
also gain lower viscosity which is a disadvantage, allowing it to flow throughout the metal crown.

79

Caution: The temperature of the slab for Zinc phosphate cements should not be ?

below the dew point of the room.

80

*** Important point: The advantages of using the cool slab method for Zinc phosphate cements are ?

• a substantial increase in the working time of the mix on the slab
• a shorter setting time of the mix after placement in the mouth

81

Which of the following statements are true regarding glass ionomer restorations? Select all that apply.
• glass ionomer is often the ideal material of choice for restoring root surface caries in patients with high caries activity
• the best surface finish for a glass ionomer restoration is that obtained against a surface matrix
• glass ionomers are somewhat esthetic and polish much better than composites
• glass ionomer adheres to mineralized tooth tissue

• glass ionomer is often the ideal material of choice for restoring root surface caries in patients with high caries activity
• the best surface finish for a glass ionomer restoration is that obtained against a surface matrix
• glass ionomer adheres to mineralized tooth tissue

82

Sometimes called ?. This technique achieves all the benefits of the glass ionomer cements plus the high polishability, surface hardness, and strong bond to enamel of the composite resin

the "sandwich technique" especially in Cl V filling

83

Which of the following materials could be used to cement a bridge and fill a cervical lesion?
• glass lonomer
• zinc oxide-eugenol
• zinc polycarboxylate
• zinc phosphate

glass lonomer (Glass ionomer cements are often used for root surface carious lesions because of the potential advantage of fluoride release in helping to control the spread of caries)

84

• among cements, the least erosion ?
• the most erosion?

• glass ionomer cements
• polycarboxylate cements

85

Zinc polycarboxylate cements are rarely used and marketed, however they were the first system to chemically bond to tooth structure.
• both statements are true
• both statements are false
• the first statement is true, the second is false
• the first statement is false, the second is true

the first statement is false, the second is true (The powder
is zinc oxide and magnesium oxide.

86

Zinc polycarboxylate cements strength regarding zinc phosphate

• a compressive strength slightly lower
• while the tensile strength is higher

87

The most commonly noted disadvantages of polycarboxylate cement is ?

its marked thickness and short working time

88

When cementing a cast restoration, always apply polycarboxylate cement to ?

both restoration and the tooth

89

When using a zinc phosphate cement you place the varnish first. This is because zinc phosphate cements are not biocompatible.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct and related

90

A/An ? base is a base that is typically placed over a calcium hydroxide base that has been placed over a pulp exposure.
• primary base
• secondary base
• direct base
• indirect base

secondary base

91

Under amalgam and tooth-colored restorations, the primary base is usually ?, whereas, under gold restorations, the primary base is usually ?. Glass ionomers are commonly used today, as well.

• calcium hydroxide
• zinc phosphate cement or zinc polycarboxylate cement

92

The most common use of a secondary base is the placement of ? over a calcium hydroxide base which has been placed over a pulpal exposure (direct pulp cap).

zinc phosphate cement (before applying varnish should be applied, to avoid sensetivity, for all other bases, varish is applied after the bases)

93

Solution liners should not be placed under composite restorations because composites do not require the pulpal protection.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

the statement is correct, but the reason is not (because they will inhibit the polymerization of the resin, Suspension liners should be used for pulpal protection in this case)

94

Cavity liners are usually classified into two main groups:
Important: The above cavity liners are now being substituted with the new dentin bonding systems or dentin sealers (e.g., Gluma or HurriSeal). The dentin bonding systems and dentin sealers are classified as solution liners

1. Solution Liner (Varnish): thin film; typical thickness range is 2 to 5 micron (0.002-0.005 mm) water insoluble
• Sets by physical reaction (drying) — just like finger nail polish
2. Suspension Liner: relatively thin film; typical thickness range is 20 to 25 micron (0.020-0.025 mm) water soluble, used to line only the dentin
• Sets by physical reaction (drying)
Commercial examples: Pulpdent and Hypo-Cal

95

Suspension liners, for example calcium hydroxide, harden intraorally by the:
• chemical reaction of acids and bases
• chemical reaction involving polymerization
• chemical reaction involving chelation
• physical reaction of drying
• physical reaction of a sol-gel transformation

physical reaction of drying

96

When removing caries, which of the following layers of dentin are affected, but not infected, and therefore do not need to be removed?
• turbid dentin
• infected dentin
• transparent dentin
• normal dentin
• subtransparent dentin

transparent dentin
• normal dentin (totally normal dentin with no bacteria)
• subtransparent dentin (Damage to the odontoblastic process by acid but no bacteria, Capable of remineralization)
• transparent dentin (same as above but softer)
• turbid dentin (zone of bacterial invasion, not capable of remineralization)
• infected dentin (decomposed dentin that is filled with bacteria. Must be totally removed prior to restoration)

97

The rate of senile caries is increasing, in part, because of the iincrease in gingival recession.
• both the statement and the reason are correct and related
• both the statement and the reason are correct but not related
• the statement is correct, but the reason is not
• the statement is not correct, but the reason is correct
• neither the statement nor the reason is correct

both the statement and the reason are correct and related

98

In older patients, rampant senile caries can be caused by ?

• poor oral hygiene,
• decreased salivary flow,
• side effects of medications.

99

Chronic caries is characterized by which of the following. Select all that apply.
• pain is common
• slowly progressing or arrested
• common in adults
• entrance to the lesion is small
• lesion is deep and narrow

• slowly progressing or arrested
• common in adults
lesion is shallow (small lesion) and entrance to the lesion is wide

100

The response of the pulp to carious attack or the trauma of operative procedures depends on ?

the blood supply of the pulp and its cellular activity

101

Defense mechanisms of the pulp (to protect it from irritation):

• initial defense (Sclerotic dentin (peritubular dentin formation))
• secondary defense (Reparative dentin (irritation dentin formation))

102

? is degraded by Streptococcus mutans into ? and ?, thereby causing caries initiation and progression.
• sucrose, glucans, lactic acid
• glucose, glucans, lactic acid
• sucrose, glucose, acetic acid
• glucose, sucrose, acetic acid

sucrose, glucans, lactic acid (while facial and lingual root surfaces may have plaque-containing filamentous actinomyces species that can cause root surface caries)

103

Fluoride treatments will dramatically reduce ?, although they are not as effective in preventing ?. ? the pits and fissures just after tooth eruption may be ? procedure to help protect these areas from caries destruction.

• smooth surface caries
• pit and fissure caries
• Sealing
• the single most important

104

The enzyme ? produced by Streptococcus mutans is the key factor in metabolic acids production by Streptococcus mutans resulting dental caries.

glucosyltransferase (Sucrose is a natural source of energy for this enzyme)

105

The initiation of caries requires four entities; choose the four entities from the following choices.
• host
• bacteria
• carbohydrates
• saliva
• time

• host
• bacteria
• carbohydrates
• time

106

Enamel demineralization occurs at pH ? or below. Remineralization of the damaged tooth structure occurs as the pH rises above that.

5.5

107

There is abundant evidence that the initiation of dental caries requires a high proportion of:
• lactobacillus within saliva
• streptococcus mutans within dental plaque
• lactobacillus within dental plaque
• streptococcus mutans within saliva

streptococcus mutans within dental plaque (Streptococcus mutans produce great amounts of lactic acid (acidogenic))

108

?, which is a natural sugar from birch trees, keeps sucrose molecules from binding with mutans streptococci. Streptococcus mutans cannot ferment xylitol. Additionally, it causes the environment to become more alkaline, inhibiting the bacterium's growth.

Xylitol

109

Streptococcus mutans are ? and therefore ?.
• acidogenic, cariogenic
• aciduric, cariostatic
• acidogenic, cariostatic
• aciduric, cariogenic

acidogenic, cariogenic