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DANB CPFDA practice questions

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Question 1Sealants

Which tooth surface is the primary target when placing a pit-and-fissure sealant?

  1. The smooth facial surface of a maxillary central incisor
  2. The interproximal contact area of two adjacent premolars
  3. The occlusal pit-and-fissure anatomy of a posterior tooth Correct answer.
  4. The cervical third of the root surface

Explanation

Pit-and-fissure sealants are placed in the morphologically deep grooves and pits of posterior occlusal, buccal, and lingual surfaces where plaque retentive anatomy makes cleaning difficult. Smooth and interproximal surfaces are not the intended sealant substrate.

Question 2Sealants

Which tooth morphology places a patient at highest risk for developing caries in a pit or fissure?

  1. A deep, narrow, non-coalesced occlusal fissure Correct answer.
  2. A shallow, wide, self-cleansing occlusal groove
  3. A rounded cusp with a broad marginal ridge
  4. A smooth buccal surface with a single shallow pit

Explanation

Deep, narrow, non-coalesced fissures trap plaque and food and resist bristle penetration, so they are the highest-risk anatomy. Shallow or wide grooves are more accessible to cleansing and are less likely to retain cariogenic biofilm.

Question 3Sealants

Which material is most commonly used for pit-and-fissure sealants today?

  1. Zinc phosphate cement
  2. Cast gold
  3. Light-cured resin-based composite sealant Correct answer.
  4. Amalgam

Explanation

Resin-based sealants, typically light-cured, are the most widely used sealant material because they bond to etched enamel and are easy to place and verify. Amalgam, zinc phosphate, and cast gold are restorative or luting materials, not sealants.

Question 4Sealants

What is the purpose of acid etching enamel before sealant application?

  1. To increase the enamel fluoride content
  2. To sterilize the enamel surface
  3. To remove the entire enamel surface layer
  4. To create microporosity that allows resin tags to penetrate and bond Correct answer.

Explanation

Phosphoric acid etching dissolves enamel crystallites and creates a microporous surface into which the resin flows, forming resin tags and micromechanical retention. It does not sterilize, remove the whole enamel layer, or add fluoride.

Question 5Sealants

Which etchant concentration is typically used for sealant placement?

  1. 5% hydrofluoric acid
  2. 37% phosphoric acid Correct answer.
  3. 10% citric acid
  4. 18% hydrochloric acid

Explanation

Phosphoric acid at approximately 30 to 40 percent, commonly 37 percent, is the standard etchant for sealant bonding to enamel. Hydrofluoric acid is used for ceramic and glass, hydrochloric acid for other purposes, and citric acid is not an enamel etchant.

Question 6Sealants

What is the correct sequence for placing a light-cured sealant?

  1. Rinse, apply sealant, etch, light cure
  2. Etch, apply sealant, rinse, light cure
  3. Etch, rinse and dry, apply sealant, light cure Correct answer.
  4. Apply sealant, etch, rinse, light cure

Explanation

The standard sequence is to isolate, etch the enamel, rinse and thoroughly dry to a frosty appearance, apply the sealant, and light cure. Etching must precede sealant application so the resin can penetrate the etched surface.

Question 7Sealants

A properly etched and dried enamel surface should appear:

  1. Glossy and translucent
  2. Wet and reflective
  3. Yellow and stained
  4. Chalky white or frosty Correct answer.

Explanation

Etched enamel that is properly rinsed and dried has a dull, chalky white or frosty appearance due to the microporous surface. A glossy or wet appearance suggests the surface is not adequately etched or has become contaminated.

Question 8Sealants

Which isolation method is recommended when placing a sealant?

  1. Rubber dam or other moisture control such as cotton rolls with a dry field Correct answer.
  2. No isolation if the patient is cooperative
  3. Moist cotton rolls left wet
  4. Saliva pooling around the tooth

Explanation

Sealant bonding requires a dry, uncontaminated field because saliva and moisture prevent resin from penetrating etched enamel. Rubber dam or careful cotton roll isolation with a dry field is required for retention.

Question 9Sealants

What should be done if the etched enamel surface becomes contaminated with saliva before sealant application?

  1. Re-etch the surface before applying the sealant Correct answer.
  2. Proceed with sealant application immediately
  3. Wipe with a dry gauze and proceed
  4. Apply a bonding agent only

Explanation

Saliva contamination blocks the etched micropores and prevents resin tag formation, so the surface must be re-etched to restore the etched pattern. Simply wiping or proceeding will compromise retention.

Question 10Sealants

Which clinical finding best indicates that a sealant has been retained successfully at recall?

  1. The sealant is missing but the fissure is still dry
  2. The sealant is present but the margins are open and stained
  3. The sealant is intact and the fissure is sealed Correct answer.
  4. The sealant is partially chipped with exposed deep fissure

Explanation

An intact sealant with all pits and fissures covered confirms successful retention and protection. Missing, chipped, or open margins leave the fissure exposed and require repair or replacement.

Question 11Sealants

A sealant is found to have a small defect at recall with no caries present. What is the most appropriate action?

  1. Apply fluoride varnish and take no other action
  2. Remove all sealant and place a large restoration
  3. Repair or replace the sealant to restore the seal Correct answer.
  4. Leave it and recheck in five years

Explanation

A localized sealant defect without caries should be repaired or replaced so the fissure remains protected. Removing sound tooth structure with a large restoration is overtreatment, and deferring repair allows caries to develop.

Question 12Sealants

Which radiograph finding would most strongly justify placing a sealant on a permanent molar?

  1. A radiolucency into dentin on the bitewing
  2. A deep occlusal fissure with no radiolucency Correct answer.
  3. A large existing amalgam restoration
  4. A periapical radiolucency

Explanation

A deep fissure without radiographic caries is a preventive sealant indication because the anatomy is plaque retentive. A radiolucency into dentin indicates caries requiring restoration, and existing restorations or periapical disease are not sealant indications.

Question 13Sealants

Which patient factor most strongly supports placing sealants on newly erupted permanent molars?

  1. Low caries risk with excellent hygiene and fluoride exposure
  2. Presence of only primary teeth
  3. High caries risk with deep fissures and limited access to care Correct answer.
  4. A history of no dental visits in childhood

Explanation

High caries risk combined with deep fissures and limited access to care is a strong indication for sealants because prevention is especially valuable when follow-up is uncertain. Low-risk patients with good hygiene and fluoride may not require sealants.

Question 14Sealants

What is the purpose of a sealant over an incipient non-cavitated occlusal lesion?

  1. To whiten the tooth
  2. To replace the need for fluoride
  3. To arrest the lesion by cutting off the cariogenic substrate Correct answer.
  4. To restore lost tooth structure and contour

Explanation

Sealing a non-cavitated incipient lesion isolates the area from plaque substrate and can arrest the lesion while preserving tooth structure. Sealants do not restore lost structure, whiten teeth, or replace fluoride.

Question 15Sealants

Which factor most affects the retention of a resin sealant?

  1. The brand of the curing light
  2. Adequate etching and a dry, uncontaminated field Correct answer.
  3. The patient's age alone
  4. The shade of the sealant

Explanation

Retention depends primarily on proper etching and maintaining a dry, uncontaminated field so resin tags can form. Sealant shade, curing light brand, and age alone do not determine bond quality.

Question 16Sealants

Which type of sealant is most appropriate for a patient with limited cooperation and no ability to maintain a dry field?

  1. A cast gold inlay
  2. A glass ionomer-based sealant that tolerates moisture Correct answer.
  3. A resin-based sealant requiring strict isolation
  4. A composite veneer

Explanation

Glass ionomer-based sealants are more moisture tolerant and release fluoride, making them an option when strict isolation is difficult. Resin sealants require a dry field, and cast gold or veneers are restorative, not preventive, options.

Question 17Sealants

A sealant is placed but the assistant notices the surface remains tacky after curing. What is the most likely cause?

  1. Excess etching time
  2. The light tip was too close to the tooth
  3. Insufficient curing time or light output Correct answer.
  4. The sealant was applied too thinly

Explanation

A tacky surface after light curing usually indicates inadequate light exposure, either from insufficient curing time or low light output. Etching time and sealant thickness do not produce an uncured surface.

Question 18Sealants

Which statement about sealant application on primary molars is correct?

  1. Sealants on primary teeth require general anesthesia
  2. Sealants are never placed on primary teeth
  3. Sealants on primary teeth are placed only after exfoliation
  4. Sealants may be placed on primary molars with deep fissures in high-risk children Correct answer.

Explanation

Primary molars with deep fissures in high caries risk children can benefit from sealants to prevent caries until exfoliation. They do not require general anesthesia, are not placed after exfoliation, and are not categorically excluded.

Question 19Sealants

Which sequence correctly describes the application of a self-etching sealant system?

  1. Apply sealant, etch, rinse, cure
  2. Rinse, apply sealant, cure, etch
  3. Etch, rinse, dry, apply sealant, cure
  4. Apply acidic primer, air thin, apply sealant, cure Correct answer.

Explanation

Self-etching systems combine etching and priming, so the acidic primer is applied, thinned with air, followed by the sealant and light curing. Separate etch-and-rinse steps are not required for these systems.

Question 20Sealants

What is the primary reason sealants are underused in high-risk populations?

  1. Sealants are ineffective in permanent teeth
  2. Sealants require general anesthesia
  3. Sealants cause enamel loss
  4. Access barriers and lack of awareness among caregivers and providers Correct answer.

Explanation

Underuse is largely driven by access barriers and limited awareness among caregivers and providers rather than lack of effectiveness. Sealants are effective in permanent teeth and do not require general anesthesia.

Question 21Sealants

A sealant placed on a partially erupted permanent molar is most likely to fail because:

  1. The occlusal surface is fully visible
  2. The enamel is fully mature
  3. The tooth is already carious
  4. Moisture from the gingival crevice contaminates the field Correct answer.

Explanation

Partially erupted molars are difficult to isolate because crevicular fluid and saliva can contaminate the etched field, leading to sealant failure. Full visibility and mature enamel would favor retention, and caries status is separate from eruption.

Question 22Sealants

Which statement best describes the evidence regarding sealant safety and fluoride release?

  1. Resin sealants release fluoride continuously
  2. Glass ionomer sealants release fluoride and may offer some additional caries inhibition Correct answer.
  3. Sealants cause systemic fluorosis
  4. Sealants eliminate the need for systemic fluoride

Explanation

Glass ionomer-based sealants can release fluoride and may provide additional local caries inhibition, although retention is generally lower than resin sealants. Resin sealants do not release fluoride continuously, and sealants do not cause fluorosis or replace systemic fluoride.

Question 23Sealants

Which clinical scenario most clearly represents an indication for sealant placement rather than restoration?

  1. A tooth with a periapical abscess
  2. A fractured cusp with exposed dentin
  3. A deep, stained, non-cavitated fissure that does not catch the explorer Correct answer.
  4. A cavitated lesion into dentin on the occlusal surface

Explanation

A deep, non-cavitated fissure that does not catch the explorer is a preventive sealant indication because the surface is intact. Cavitated dentinal lesions, fractures with exposed dentin, and periapical abscesses require restorative or endodontic care.

Question 24Sealants

Which factor would most likely lead to a decision to re-etch and reseal rather than simply monitor?

  1. An intact sealant with no staining
  2. A sealant on a low-risk patient with no defects
  3. A sealant with a marginal defect and visible staining at the interface Correct answer.
  4. A sealant placed five years ago with full coverage

Explanation

A marginal defect with staining suggests leakage and loss of seal, so re-etching and resealing is warranted to protect the fissure. Intact sealants with full coverage and no defects can be monitored.

Question 25Sealants

Which statement best explains why sealants are effective despite concerns about sealing over bacteria?

  1. Sealing cuts off nutrients, and entrapped bacteria cannot progress Correct answer.
  2. Sealants dissolve enamel to release fluoride
  3. Sealants are placed only on sterile teeth
  4. Sealants kill all bacteria instantly

Explanation

Sealing over a non-cavitated lesion cuts off the bacterial nutrient supply, and entrapped organisms cannot progress, so the lesion arrests. Sealants do not instantly kill bacteria, dissolve enamel, or require sterile teeth.

Question 26Sealants

A resin-based sealant is being placed on a newly erupted permanent molar. Which enamel condition is most critical for achieving micromechanical retention?

  1. Enamel that has been etched with phosphoric acid to create micropores Correct answer.
  2. Enamel that has been polished with a non-fluoridated pumice to remove plaque
  3. Enamel that has been moistened with a bonding agent before sealant application
  4. Enamel that has been air-dried after etching to a chalky, frosted appearance

Explanation

Resin sealants bond to enamel primarily through micromechanical retention into micropores created by acid etching, typically with 35-37% phosphoric acid. The etched pattern increases surface area and allows resin tags to penetrate. Polishing removes debris but does not create retention; moisture and bonding agents are separate steps and do not replace etching.

Question 27Sealants

Which sealant material is supplied as a two-liquid system that polymerizes via a chemical reaction and is therefore less dependent on light-curing depth?

  1. Compomer sealant
  2. Auto-polymerized resin sealant Correct answer.
  3. Glass ionomer sealant
  4. Light-cured resin sealant

Explanation

Auto-polymerized (chemical-cure) resin sealants set through a chemical reaction between two components, so they do not require a light source and are not limited by curing-light penetration depth. Light-cured sealants depend on adequate light exposure. Glass ionomer and compomer sealants set through acid-base reactions but are not typically two-liquid resin systems.

Question 28Sealants

During sealant placement, the clinician isolates the tooth with a rubber dam. Which advantage does this provide compared with cotton rolls alone?

  1. It eliminates the need to etch the enamel
  2. It removes the need for a postoperative occlusal check
  3. It allows the sealant to cure without a light source
  4. It provides a consistently dry field and retracts soft tissues Correct answer.

Explanation

A rubber dam provides excellent moisture control and soft-tissue retraction, which are critical because saliva contamination reduces sealant retention. It does not replace etching, does not eliminate the need for light curing of light-cured materials, and does not remove the need to check the occlusion after placement.

Question 29Sealants

Which statement accurately describes the rationale for using a fluoride-releasing glass ionomer sealant in a community program with limited equipment?

  1. It provides sustained fluoride release and can be placed without a curing light Correct answer.
  2. It is contraindicated for newly erupted molars
  3. It requires a shorter etching time than resin sealants
  4. It has higher retention rates than resin sealants in all situations

Explanation

Glass ionomer sealants release fluoride and, in some formulations, set without a light, making them practical in outreach settings. Their retention is generally lower than that of resin sealants, but they may still provide caries-preventive benefit. They are not contraindicated for newly erupted molars and do not necessarily require shorter etching.

Question 30Sealants

A sealant is being placed on a permanent first molar with a deep, narrow occlusal pit. After etching and drying, the clinician notices the enamel surface is uniformly frosted. What is the next step?

  1. Re-etch the tooth because the frosted appearance indicates over-etching
  2. Apply the sealant immediately, ensuring it flows into the pit Correct answer.
  3. Apply a bonding agent and light-cure before sealant placement
  4. Wipe the surface with a moist cotton pellet to remove the frost

Explanation

A uniformly frosted (chalky white) enamel surface after etching indicates successful conditioning, so the sealant should be applied promptly while the field remains dry. Re-etching is unnecessary, moisture would contaminate the etched surface, and a bonding agent is not required for standard sealant placement unless the product instructions specify it.

Question 31Sealants

Which technique is recommended to verify that a sealant has fully seated into the occlusal pits and fissures during placement?

  1. Use a gentle stream of air to thin the sealant before curing
  2. Apply additional etchant over the sealant before curing
  3. Probe the sealant with a sharp explorer before curing Correct answer.
  4. Inspect the sealant with a mirror after light-curing

Explanation

Before curing, gently probing the sealant with an explorer helps confirm that it has flowed into the pits and fissures and that no voids or air bubbles are present. After curing, inspection with a mirror is also performed, but pre-cure probing allows correction. Air thinning can displace material, and etchant should not be applied over sealant.

Question 32Sealants

After light-curing a sealant, the clinician notices that the material remains soft and tacky. Which factor is the most likely cause?

  1. The curing light output was inadequate or the tip was too far from the tooth Correct answer.
  2. The sealant was applied too thinly
  3. The etching step was performed for too long
  4. The enamel was contaminated with saliva before etching

Explanation

A soft, tacky sealant after curing most often indicates insufficient light exposure, such as low light output, a dirty tip, or incorrect distance and angulation. Etching time, sealant thickness, and pre-etch contamination affect retention but do not typically prevent polymerization. The clinician should verify the curing light and re-cure or replace the sealant.

Question 33Sealants

A parent asks why a sealant is being recommended for a child's newly erupted permanent molar that has no visible decay. Which explanation best reflects the evidence base?

  1. Sealants eliminate the need for future fluoride exposure
  2. Sealants prevent caries by physically blocking bacteria and food from deep pits and fissures Correct answer.
  3. Sealants are placed only after caries is detected radiographically
  4. Sealants are effective only on primary teeth

Explanation

Sealants work by creating a physical barrier that prevents cariogenic bacteria and food debris from accumulating in susceptible pits and fissures. They are indicated for caries prevention on newly erupted permanent molars, not only after caries is detected. They do not replace fluoride, and they are effective on both primary and permanent teeth.

Question 34Sealants

Which statement best describes the recommended handling of a sealant that has been contaminated with saliva after etching but before sealant application?

  1. Re-etch the enamel, rinse, and dry before applying sealant Correct answer.
  2. Apply a layer of etchant over the saliva and cure
  3. Proceed with sealant application because saliva does not affect etched enamel
  4. Dry the surface with air and apply sealant immediately

Explanation

Saliva contamination of etched enamel reduces bond strength by blocking micropores, so the enamel must be re-etched, rinsed, and dried to restore the etched pattern before sealant application. Simply drying or proceeding without re-etching compromises retention. Etchant should not be applied over saliva and cured.

Question 35Sealants

At a recall visit, a sealant on a permanent molar is partially lost, exposing an intact, caries-free occlusal surface. What is the most appropriate clinical action?

  1. Re-etch the exposed enamel and replace the sealant Correct answer.
  2. Monitor the tooth and apply fluoride varnish only
  3. Place a restoration because the sealant has failed
  4. Remove the remaining sealant and leave the tooth unsealed

Explanation

When a sealant is partially lost but the underlying enamel is sound, the appropriate action is to re-etch the exposed area and replace the sealant to maintain caries protection. Placing a restoration is unnecessary because there is no caries. Monitoring alone leaves the tooth unprotected, and removing the remaining sealant would be counterproductive.

Question 36Sealants

Which patient history finding most strongly suggests that sealants should be considered for a child's permanent molars?

  1. The child consumes a low-sugar diet
  2. The child's sibling had multiple pit-and-fissure caries Correct answer.
  3. The child has had no caries in any teeth
  4. The child has several incipient smooth-surface lesions

Explanation

A sibling with multiple pit-and-fissure caries suggests a familial pattern of high caries risk, which supports sealant placement on susceptible molars. A caries-free history and low-sugar diet are lower-risk indicators. Incipient smooth-surface lesions indicate caries activity but do not specifically point to pit-and-fissure risk as strongly as a sibling history of fissure caries.

Question 37Sealants

Which statement about the use of a bonding agent under a resin sealant is most accurate?

  1. A bonding agent prevents the need for etching
  2. A bonding agent is always required for sealant retention
  3. A bonding agent should be applied only after the sealant is cured
  4. A bonding agent may improve retention on contaminated or difficult-to-isolate surfaces Correct answer.

Explanation

Some clinicians use a bonding agent under sealants to improve adaptation and retention, particularly when isolation is challenging or enamel is atypical. However, it is not universally required, and it does not replace etching. Bonding agent is applied before sealant and cured according to manufacturer instructions, not after sealant curing.

Question 38Sealants

Which statement best explains why sealants remain effective even when placed over early, non-cavitated carious lesions?

  1. The sealant allows saliva to flush the lesion more effectively
  2. The sealant kills all bacteria immediately upon application
  3. The sealant promotes remineralization by releasing calcium
  4. The sealant physically seals off the lesion from fermentable carbohydrates, arresting progression Correct answer.

Explanation

Sealing a non-cavitated lesion cuts off the bacteria's access to fermentable carbohydrates, which arrests lesion progression and prevents cavitation. Sealants do not necessarily kill bacteria immediately, do not primarily release calcium, and do not enhance salivary flushing. The physical barrier is the key mechanism.

Question 39Sealants

Which factor most directly determines the long-term success of a resin sealant on a permanent molar?

  1. The patient's age at the time of placement
  2. The use of a postoperative fluoride varnish
  3. The brand of sealant material used
  4. The quality of isolation and absence of contamination during placement Correct answer.

Explanation

Retention of resin sealants depends heavily on maintaining a dry, uncontaminated field during etching and application, because moisture interferes with resin penetration. Material brand, patient age, and postoperative fluoride are less critical than isolation quality. Good isolation ensures proper etching and bonding.

Question 40Sealants

A dental assistant is preparing to place a resin-based sealant on a permanent molar and wants to confirm that the enamel has been adequately etched. After applying etchant, rinsing, and drying, which appearance indicates the enamel is ready for sealant application?

  1. A uniformly frosted, opaque white surface Correct answer.
  2. A chalky surface with scattered dark brown pits
  3. A glossy, translucent surface with visible sheen
  4. A smooth surface with a slight yellow tint

Explanation

Properly etched enamel loses its surface gloss and takes on a uniformly frosted, opaque white appearance, which indicates that the prismatic structure has been opened for micromechanical retention. If the surface remains glossy or translucent, the etch was inadequate or the enamel was contaminated and must be re-etched.

Question 41Coronal Polishing

Which instrument is specifically designed for applying polishing paste to the coronal surfaces of teeth?

  1. A #12 dental explorer
  2. A rubber polishing cup mounted on a slow-speed handpiece Correct answer.
  3. A periodontal curette
  4. A straight fissure bur

Explanation

Coronal polishing is performed with a rubber cup or bristle brush attached to a slow-speed contra-angle handpiece, which holds the abrasive paste against the enamel. Hand scalers and explorers are diagnostic or debridement instruments and cannot carry paste effectively.

Question 42Coronal Polishing

The primary purpose of coronal polishing is to:

  1. Whiten the dentin by bleaching from within
  2. Flatten the enamel surface to reduce caries risk
  3. Remove extrinsic stains and plaque from the clinical crowns Correct answer.
  4. Remove supragingival and subgingival calculus deposits

Explanation

Coronal polishing removes plaque and extrinsic stains from the exposed tooth surfaces using an abrasive agent. It does not remove calculus, which requires scaling, and it does not alter internal tooth color.

Question 43Coronal Polishing

Which abrasive is the most commonly used active ingredient in commercially prepared prophylaxis paste?

  1. Sodium fluoride
  2. Pumice Correct answer.
  3. Chlorhexidine gluconate
  4. Calcium hydroxide

Explanation

Pumice is a volcanic abrasive that is the traditional and most common abrasive in prophylaxis paste, available in fine, medium, and coarse grits. The other listed agents are therapeutic or non-abrasive compounds, not abrasives.

Question 44Coronal Polishing

Before polishing a patient's teeth, the clinician should first:

  1. Place a rubber dam on the affected teeth
  2. Anesthetize the quadrant to be polished
  3. Assess the teeth and record existing restorations and conditions Correct answer.
  4. Apply a fluoride varnish to all surfaces

Explanation

Polishing requires a preliminary assessment so the clinician knows where restorations, exposed cementum, and demineralized areas are located and can avoid damaging them. Anesthesia and rubber dams are not routine for polishing, and fluoride timing relates to the end of the appointment.

Question 45Coronal Polishing

Which condition is a contraindication to coronal polishing?

  1. Presence of extrinsic coffee stain
  2. Presence of materia alba
  3. Teeth with light plaque biofilm
  4. Teeth with newly erupted, immature enamel Correct answer.

Explanation

Newly erupted enamel is incompletely mineralized and more susceptible to abrasion, so polishing is deferred until the enamel matures. Extrinsic stain, materia alba, and plaque biofilm are precisely the deposits polishing is meant to remove.

Question 46Coronal Polishing

During coronal polishing, the rubber cup should be operated with:

  1. A dry cup with no paste for the final pass
  2. High-speed rotation at maximum rpm
  3. Sustained heavy pressure held on one spot
  4. Intermittent pressure and continuous motion to avoid heat buildup Correct answer.

Explanation

Intermittent, light pressure with continuous movement prevents frictional heat and gouging of the enamel or gingiva. Sustained pressure in one location generates heat and can abrade tooth structure excessively.

Question 47Coronal Polishing

Polishing paste is applied to the rubber cup by:

  1. Loading a small amount onto the cup from a single-use dispenser Correct answer.
  2. Dipping the cup into a bulk container shared among operatories
  3. Coating the entire handpiece with paste
  4. Spraying paste directly into the patient's mouth

Explanation

Paste should be dispensed in single-use portions from a dispenser to prevent cross-contamination. Dipping a used cup into a bulk container contaminates the supply for subsequent patients.

Question 48Coronal Polishing

After polishing, the patient's teeth and oral cavity should be:

  1. Left unrinsed to allow residual paste to remain
  2. Rinsed thoroughly to remove residual abrasive and debris Correct answer.
  3. Dried with compressed air only, without rinsing
  4. Sealed with a coat of unfilled resin

Explanation

Thorough rinsing and evacuation remove residual abrasive paste, plaque, and debris so the patient does not swallow them. Leaving paste behind is unpleasant and provides no benefit.

Question 49Coronal Polishing

A patient requests polishing but has heavy supragingival calculus. What is the correct sequence?

  1. Polish first, then scale the calculus
  2. Refuse all treatment for the appointment
  3. Scale to remove calculus, then polish the remaining surfaces Correct answer.
  4. Polish only the areas without calculus

Explanation

Polishing is performed after scaling because the abrasive cup cannot remove calculus and would simply burnish over deposits. Removing calculus first allows the paste to reach and clean the enamel surface.

Question 50Coronal Polishing

Which polishing agent selection is most appropriate for a patient with exposed root surfaces and existing composite restorations?

  1. Aluminum oxide paste at maximum rpm
  2. Coarse pumice with a stiff bristle brush
  3. A fine-grit, low-abrasion paste applied with a soft rubber cup Correct answer.
  4. Medium pumice applied with a rotating bristle brush at high speed

Explanation

Exposed cementum and composite restorations are easily scratched, so a fine, low-abrasion paste with a soft cup and light pressure is preferred. Coarse abrasives and stiff brushes increase surface roughness and damage to restorative margins.