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NDAEB Theory Exam study materials
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NDAEB Theory Exam practice questions

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Question 1Chairside dental assisting (Level I)

Which instrument is most appropriate for removing supragingival calculus from the facial surfaces of the anterior teeth?

  1. A mouth mirror
  2. An ultrasonic scaler tip
  3. A periodontal probe
  4. A sickle scaler Correct answer.

Explanation

Sickle scalers have a pointed tip and two cutting edges and are designed for supragingival calculus removal on crown surfaces. Their design allows access to the facial and lingual surfaces of anterior teeth where deposits sit above the gingival margin. Periodontal probes and mirrors are assessment tools, not calculus removal instruments.

Question 2Chairside dental assisting (Level I)

During a restorative procedure, the dentist asks for a matrix band. What is the primary purpose of this item?

  1. To isolate the tooth from saliva
  2. To retract the gingival tissue during preparation
  3. To restore the proximal contour and contain restorative material Correct answer.
  4. To protect the adjacent tooth from the bur

Explanation

A matrix band surrounds the prepared tooth to recreate the missing proximal wall so that restorative material can be condensed and shaped. It helps establish proper contact and contour with the adjacent tooth. Isolation and tissue retraction are functions of other items such as cotton rolls, suction, or retraction cord.

Question 3Chairside dental assisting (Level I)

Which of the following is the correct order for donning personal protective equipment before a procedure?

  1. Gloves, mask, eyewear, gown
  2. Eyewear, gloves, mask, gown
  3. Gown, mask, eyewear, gloves Correct answer.
  4. Mask, gloves, gown, eyewear

Explanation

PPE is applied from cleanest to most contaminated, so the gown goes on first, followed by the mask and protective eyewear, with gloves last. Gloves are donned last because they become contaminated immediately and would transfer contamination to other items if handled afterward. Removing PPE follows the reverse principle, with gloves removed first.

Question 4Chairside dental assisting (Level I)

A patient seated in the dental chair begins to cough and gag during treatment. Which action should the assistant take first?

  1. Stop treatment, sit the patient upright, and allow the airway to clear Correct answer.
  2. Lower the chair fully and continue suctioning the throat
  3. Hand the patient a cup of water to swallow
  4. Place a bite block and continue the procedure

Explanation

When a patient gags or coughs, the priority is airway safety, so treatment stops and the patient is repositioned upright to allow clearing. Suction may be used to remove accumulated fluid once the patient is upright. Continuing treatment or giving fluids while the patient is reclined increases aspiration risk.

Question 5Chairside dental assisting (Level I)

Which of the following best describes the correct technique for transferring an instrument to the dentist using the single-handed method?

  1. Hand the instrument over with the working end pointing toward the dentist
  2. Hold the instrument near the working end and pass it across the patient's face
  3. Grip the instrument mid-handle so the handle end is positioned into the dentist's fingers Correct answer.
  4. Place the instrument in the dentist's palm with the handle parallel to the floor

Explanation

In single-handed transfer, the assistant holds the instrument so the handle end is presented into the dentist's fingers without the two looking at each other. The working end stays directed away from the patient and the dentist's hand. The transfer should occur in the zone over the patient's chest, not across the face.

Question 6Chairside dental assisting (Level I)

Which of the following is the primary reason for maintaining a clear field of vision with the dental mirror during a procedure?

  1. To improve lighting on the tooth surface
  2. To retract the tongue and cheek
  3. To allow indirect visualization of areas not directly visible Correct answer.
  4. To protect the patient's soft tissue

Explanation

The mirror's primary function is indirect vision, allowing the operator to see surfaces such as the lingual of anterior teeth or the palatal surfaces that cannot be viewed directly. Improved lighting and tissue retraction are secondary benefits. Protecting soft tissue is not a primary function of the mirror.

Question 7Chairside dental assisting (Level I)

Which of the following is the most appropriate method for cleaning a contaminated high-speed handpiece after use?

  1. Rinse the handpiece under tap water and return it to the drawer
  2. Wipe the handpiece with alcohol and store it uncapped
  3. Wipe the exterior with a disinfectant wipe and sterilize the handpiece according to the manufacturer's instructions Correct answer.
  4. Soak the handpiece in cold sterile water overnight

Explanation

Handpieces are semi-critical items and must be cleaned and then sterilized according to the manufacturer's validated instructions, typically by autoclave. External surfaces are wiped to remove debris before processing. Soaking in water or simple alcohol wiping does not achieve sterilization.

Question 8Chairside dental assisting (Level I)

Which of the following describes the correct way to position the dental assistant's stool relative to the patient's chair during four-handed dentistry?

  1. At the head of the chair, facing the patient's feet
  2. On the dentist's side, behind the dentist
  3. At the foot of the chair, facing the dentist
  4. On the opposite side of the patient's head from the dentist, with thighs under the patient's headrest Correct answer.

Explanation

The assistant sits on the opposite side of the patient's head from the dentist, with thighs positioned under the headrest to maintain close access and neutral posture. This position allows efficient transfer of instruments and suction without reaching across the patient. Sitting at the foot or behind the dentist disrupts the working triangle.

Question 9Chairside dental assisting (Level I)

A patient reports a history of latex allergy. Which of the following is the most appropriate action before treatment?

  1. Proceed with latex gloves and monitor the patient
  2. Use latex-free gloves and latex-free supplies such as dams and prophy cups Correct answer.
  3. Ask the patient to take an antihistamine before the appointment
  4. Use latex gloves but double-glove

Explanation

For a latex-allergic patient, all latex-containing items in the operatory must be avoided, including gloves, rubber dams, prophy cups, and other items with natural rubber latex. Latex-free alternatives are substituted to prevent a reaction. Double-gloving with latex still exposes the patient to latex allergens.

Question 10Chairside dental assisting (Level I)

Which of the following is the correct action when taking a radiograph using a digital sensor?

  1. Rinse the sensor under running water after use
  2. Sterilize the sensor in the autoclave between patients
  3. Hold the sensor with a gloved hand directly against the tooth
  4. Place the sensor in a barrier sleeve before positioning it in the patient's mouth Correct answer.

Explanation

Digital sensors cannot be heat-sterilized or immersed in water, so they are covered with a disposable barrier sleeve before intraoral placement. The sleeve is removed and discarded after use, and the sensor is then disinfected per manufacturer instructions. Autoclaving or rinsing would damage the electronic components.

Question 11Chairside dental assisting (Level I)

Which of the following is the primary purpose of using a rubber dam during endodontic treatment?

  1. To shorten the appointment time
  2. To improve the taste of irrigating solutions
  3. To isolate the tooth, protect the airway, and maintain a dry field Correct answer.
  4. To reduce the need for local anesthesia

Explanation

A rubber dam isolates the treatment tooth from oral fluids and protects the patient from swallowing or aspirating small instruments and irrigants. It also maintains a dry, clean field for restorative and endodontic materials. It does not replace anesthesia or directly shorten appointments.

Question 12Chairside dental assisting (Level I)

Which of the following is the most appropriate way to manage a patient who becomes pale, sweaty, and dizzy during a procedure?

  1. Ask the patient to sit up and take deep breaths
  2. Continue treatment and reassure the patient
  3. Give the patient a sugary drink immediately
  4. Place the patient in a supine position and monitor vital signs Correct answer.

Explanation

Pallor, diaphoresis, and dizziness suggest a vasovagal response or syncope, so treatment stops and the patient is placed supine with vital signs monitored. Raising the legs may also improve venous return. Continuing treatment or sitting the patient up can worsen the episode.

Question 13Chairside dental assisting (Level I)

Which of the following best describes the role of the dental assistant in maintaining the chain of asepsis during a procedure?

  1. The assistant avoids touching any instruments during the procedure
  2. Only the dentist handles sterile instruments
  3. The assistant uses sterile gloves and touches only sterile items in the sterile field Correct answer.
  4. The assistant can touch non-sterile items as long as gloves remain on

Explanation

Chain of asepsis means sterile items are handled only with sterile gloves and kept separate from non-sterile surfaces. The assistant supports this by maintaining the sterile field and avoiding contact between sterile and non-sterile items. Touching non-sterile surfaces with sterile gloves breaks the chain.

Question 14Chairside dental assisting (Level I)

Which of the following is the correct way to dispose of a used anesthetic needle after an injection?

  1. Break the needle off the syringe and discard it in the trash
  2. Place the uncapped needle directly into a puncture-resistant sharps container without recapping Correct answer.
  3. Place the syringe in a biohazard bag and recap the needle with one hand
  4. Recap the needle using two hands and place it in the sharps container

Explanation

Needles should never be recapped, bent, or broken; the safest practice is to place the uncapped needle directly into a puncture-resistant sharps container immediately after use. Recapping, even with one hand, increases the risk of a needlestick injury. Sharps containers must be closable and leak-resistant.

Question 15Chairside dental assisting (Level I)

During a procedure, the dentist requests a high-volume evacuator and a saliva ejector simultaneously. Which of the following best explains this combination?

  1. The high-volume evacuator is used only for retraction
  2. Both devices perform identical functions and are used interchangeably
  3. The saliva ejector is used only for surgical procedures
  4. The high-volume evacuator removes large volumes of fluid and debris while the saliva ejector manages pooled saliva Correct answer.

Explanation

The high-volume evacuator removes large volumes of fluid and debris quickly, while the saliva ejector manages pooled saliva and keeps the field dry. The two devices serve complementary functions and are often used together. Neither device is limited to surgical retraction.

Question 16Chairside dental assisting (Level I)

Which of the following best explains why the dental assistant should maintain neutral wrist posture while scaling?

  1. It eliminates the need for sharpening instruments
  2. It increases the force applied to the tooth
  3. It reduces the risk of musculoskeletal injury and improves control Correct answer.
  4. It allows the assistant to skip PPE

Explanation

Neutral wrist posture keeps the hand and forearm aligned, reducing strain on tendons and joints during repetitive scaling motions. This improves control and reduces fatigue and the risk of cumulative trauma disorders. Posture does not replace instrument sharpening or PPE.

Question 17Chairside dental assisting (Level I)

Which of the following is the correct action when a patient's medical history reveals they are taking a blood thinner such as warfarin?

  1. Recommend the patient take aspirin before treatment
  2. Proceed with treatment without informing the dentist
  3. Record the medication and alert the dentist before treatment Correct answer.
  4. Stop the patient's medication before the appointment

Explanation

Medication use, including anticoagulants, must be recorded and reported to the dentist so the treatment plan can account for bleeding risk. The assistant does not advise patients to stop or change prescribed medications. Alerting the dentist allows appropriate precautions to be taken.

Question 18Exposes dental radiographs

Which film size is most commonly used for a full-mouth series of periapical radiographs on an adult?

  1. Size 0
  2. Size 4
  3. Size 2 Correct answer.
  4. Size 1

Explanation

Size 2 film is the standard periapical receptor for adults because it covers the full length of most roots along with the coronal portion of the tooth and surrounding bone. Size 0 and size 1 are too small for routine adult periapicals, and size 4 is an occlusal film.

Question 19Exposes dental radiographs

A radiograph appears generally light with low density overall. Which exposure factor change would most directly increase film density?

  1. Increase the milliamperage-seconds Correct answer.
  2. Increase the source-to-receptor distance
  3. Decrease the kilovoltage peak
  4. Decrease the developing time

Explanation

Density on a radiograph is primarily controlled by the number of x-ray photons reaching the receptor, which is governed by milliamperage-seconds. Raising mA-seconds increases the quantity of radiation and therefore darkens the image.

Question 20Exposes dental radiographs

What is the purpose of placing a lead apron on the patient during radiographic exposure?

  1. To shorten the developing cycle
  2. To sharpen the image contrast
  3. To reduce scatter radiation reaching the patient's body Correct answer.
  4. To stabilize the film holder in the mouth

Explanation

A lead apron absorbs radiation that would otherwise scatter within the patient's tissues and reach radiosensitive organs. It protects the patient's trunk and thyroid region and does not affect image quality or processing.

Question 21Exposes dental radiographs

Which technique is used to expose a maxillary molar periapical when the patient has a shallow palate and a small mouth?

  1. Occlusal technique
  2. Paralleling technique with a bite block Correct answer.
  3. Bisecting angle technique with the film held by finger
  4. Panoramic technique

Explanation

The paralleling technique with a receptor holder keeps the film parallel to the long axis of the tooth and the beam perpendicular, giving accurate dimensional images without depending on the patient's finger. It is the preferred method whenever a holder can be seated, even in a shallow palate, by using a smaller receptor or adjusting the bite block.

Question 22Exposes dental radiographs

In the bisecting angle technique, the central ray should be directed:

  1. At a 45-degree angle to the occlusal plane
  2. Perpendicular to the imaginary bisector between the tooth and the film Correct answer.
  3. Parallel to the film plane
  4. Parallel to the long axis of the tooth

Explanation

The bisecting angle rule states that the central ray must be perpendicular to the imaginary line bisecting the angle formed by the long axis of the tooth and the plane of the film. This geometry makes the projected tooth length equal the actual length, minimizing distortion.

Question 23Exposes dental radiographs

A periapical radiograph shows the crowns of the teeth but the root apices are cut off. What is the most likely cause?

  1. The film was not positioned to include the apices Correct answer.
  2. The film was placed too high in the maxillary arch
  3. The film was overdeveloped
  4. The exposure time was too short

Explanation

When apices are missing from the image, the receptor was not positioned far enough apically to record the root ends. The correction is to reposition the film so its border extends beyond the apex, keeping the beam centered on the tooth.

Question 24Exposes dental radiographs

Which of the following best describes the appearance of a bitewing radiograph?

  1. It shows the entire tooth including the apex
  2. It shows only the mandibular anterior teeth
  3. It shows the temporomandibular joint
  4. It shows the crowns and alveolar crest of both arches Correct answer.

Explanation

A bitewing is exposed with the film held by a tab or bite block and shows the coronal portions of the maxillary and mandibular teeth along with the alveolar crest. It is used primarily to detect interproximal caries and crestal bone levels.

Question 25Exposes dental radiographs

During processing, a film is accidentally exposed to light before development. What is the most likely result?

  1. A film with a green tint
  2. A clear film with no image
  3. A completely black film Correct answer.
  4. A film with increased contrast

Explanation

Unexposed silver halide crystals are light sensitive; exposure to light before development reduces them to metallic silver across the entire film. The result is a uniformly black, fogged radiograph with no diagnostic image.

Question 26Exposes dental radiographs

Which of the following is the primary advantage of a digital intraoral sensor over film?

  1. It never requires retakes
  2. It allows immediate image viewing and reduced dose Correct answer.
  3. It eliminates the need for infection control
  4. It requires no radiation exposure

Explanation

Digital receptors capture the image electronically so it can be viewed almost instantly, and most systems require less exposure than film. This speed and dose reduction are the main clinical advantages, though proper technique and barriers are still required.

Question 27Exposes dental radiographs

A patient reports a strong gag reflex. Which modification best helps obtain a diagnostic periapical?

  1. Use a smaller receptor and have the patient breathe through the nose Correct answer.
  2. Angle the beam steeply from the occlusal
  3. Ask the patient to hold the film with a finger
  4. Increase the exposure time

Explanation

A smaller receptor reduces the bulk in the mouth, and slow nasal breathing helps suppress the gag reflex by relaxing the soft palate. These measures improve tolerance without compromising the image.

Question 28Exposes dental radiographs

What is the recommended position of the central ray for a maxillary anterior periapical using the paralleling technique?

  1. Parallel to the long axis of the tooth
  2. Angled 15 degrees upward
  3. Angled 20 degrees downward
  4. Perpendicular to the film and through the contact point Correct answer.

Explanation

In the paralleling technique, the central ray must be perpendicular to both the receptor and the long axis of the tooth, which means it passes through the interproximal contact area. This geometry minimizes distortion and overlap.

Question 29Exposes dental radiographs

Which film size is most appropriate for a bitewing radiograph in an adult?

  1. Size 1
  2. Size 2 Correct answer.
  3. Size 0
  4. Size 3

Explanation

Size 2 film is the standard bitewing size for adults because it covers the posterior teeth of both arches in one exposure. Size 1 is used for children or limited areas, and size 3 is a long bitewing that is less commonly used.

Question 30Exposes dental radiographs

A radiograph shows overlapping proximal contacts of the maxillary premolars. What is the most likely cause?

  1. The lead apron was not used
  2. The central ray was not directed through the interproximal spaces Correct answer.
  3. The film was overdeveloped
  4. The exposure time was too long

Explanation

Overlap occurs when the horizontal angulation of the central ray is incorrect, so the beam does not pass through the contact areas. Adjusting the horizontal angle to align the beam with the interproximal spaces eliminates the overlap.

Question 31Exposes dental radiographs

Which structure is typically seen as a radiolucent band across the roots of the maxillary teeth on a periapical radiograph?

  1. The nasal septum
  2. The incisive foramen
  3. The maxillary sinus Correct answer.
  4. The zygomatic process

Explanation

The maxillary sinus appears as a radiolucent area overlying the roots of the maxillary posterior teeth. Its inferior border can create a radiopaque line, and its position must be recognized to avoid mistaking sinus anatomy for pathology.

Question 32Exposes dental radiographs

What is the purpose of the collimator in an intraoral x-ray unit?

  1. To cool the anode
  2. To measure the exposure time
  3. To filter low-energy x-rays from the beam
  4. To restrict the size of the useful beam Correct answer.

Explanation

The collimator is a lead diaphragm that limits the diameter of the useful beam, reducing the area of patient tissue irradiated. Filtration is a separate function performed by aluminum discs in the tube head.

Question 33Exposes dental radiographs

A dental radiograph reveals a radiolucent area at the apex of a mandibular first molar with a history of deep caries. Which interpretation is most appropriate?

  1. Possible periapical pathology requiring clinical correlation Correct answer.
  2. Normal bone trabeculation
  3. Normal mental foramen
  4. Artifact from film bending

Explanation

A well-defined radiolucency at the apex of a carious tooth suggests periapical inflammatory disease, but radiographic findings must be correlated with clinical signs and vitality testing. The radiograph alone does not establish a definitive diagnosis.

Question 34Exposes dental radiographs

Which of the following is the correct order of steps for manual film processing?

  1. Develop, rinse, fix, wash, dry Correct answer.
  2. Wash, develop, fix, rinse, dry
  3. Fix, develop, wash, dry, rinse
  4. Develop, fix, wash, rinse, dry

Explanation

Manual processing begins with development to reduce exposed silver halide to metallic silver, followed by a brief rinse, fixation to remove unexposed crystals and harden the emulsion, then washing and drying. Reversing development and fixation would destroy the image.

Question 35Provides oral hygiene instruction

Which toothbrush bristle stiffness is generally recommended for an adult with healthy gums and no recession?

  1. Hard bristles
  2. Extra-hard bristles
  3. Medium bristles
  4. Soft bristles Correct answer.

Explanation

Soft bristles flex against the gingival margin and remove plaque effectively while reducing the risk of abrasion to enamel and gingival tissue. Hard and medium bristles remove plaque no better and are associated with gingival recession and cervical abrasion when used with force.

Question 36Provides oral hygiene instruction

What is the most appropriate interdental cleaning aid for a patient with open embrasure spaces and root exposure from periodontal recession?

  1. Wooden toothpick
  2. Rubber tip stimulator
  3. Interdental brush sized to the space Correct answer.
  4. Waxed dental floss

Explanation

Open embrasures and exposed roots create spaces that floss cannot adequately clean because floss contacts only the proximal surfaces it can reach. An interdental brush sized to fit the space without forcing cleans the proximal surfaces and root surfaces directly.

Question 37Provides oral hygiene instruction

A patient reports brushing twice daily but still has generalized marginal bleeding. Which instructional change most directly addresses plaque at the gingival margin?

  1. Switching to a larger brush head
  2. Increasing brushing force
  3. Demonstrating the modified Bass sulcular technique Correct answer.
  4. Adding a chlorhexidine rinse as the only measure

Explanation

Marginal bleeding reflects plaque retained at the gingival margin, so instruction should target bristle placement in the sulcus at a 45-degree angle with gentle vibratory strokes. The modified Bass technique specifically disrupts subgingival and marginal plaque.

Question 38Provides oral hygiene instruction

Which statement best describes the purpose of disclosing solution during an oral hygiene instruction session?

  1. It whitens the teeth temporarily
  2. It stains plaque so the patient can see missed areas Correct answer.
  3. It reduces gingival inflammation directly
  4. It desensitizes exposed dentin

Explanation

Disclosing agents dye plaque biofilm so patients can visualize where brushing and interdental cleaning were ineffective. This visual feedback improves self-assessment and motivates correction of technique.

Question 39Provides oral hygiene instruction

Which flossing step is most often performed incorrectly and leaves proximal plaque behind?

  1. Curving the floss into a C shape around each tooth
  2. Snapping the floss straight through the contact and moving only up and down Correct answer.
  3. Using about 45 cm of floss per session
  4. Wrapping floss around the middle fingers

Explanation

Floss must be wrapped into a C shape and slid gently beneath the papilla so it hugs each proximal surface and reaches the sulcus. Snapping through the contact and moving only vertically leaves the curved proximal surfaces uncleaned and can traumatize tissue.

Question 40Provides oral hygiene instruction

A patient with arthritis has limited hand dexterity. Which adaptation best supports independent daily plaque control?

  1. Recommending floss only
  2. Enlarging the toothbrush handle with a foam grip Correct answer.
  3. Advising the patient to brush less often
  4. Switching to a hard-bristle brush

Explanation

Enlarged or adapted handles improve grasp and control for patients with reduced dexterity, allowing effective brushing. Powered brushes and floss holders are additional options that preserve independence.

Question 41Provides oral hygiene instruction

Which fluoride concentration is typical of an over-the-counter dentifrice marketed for caries prevention in adults?

  1. 500 ppm
  2. 1,000 to 1,500 ppm Correct answer.
  3. 100 ppm
  4. 5,000 ppm

Explanation

Standard over-the-counter adult toothpastes generally contain 1,000 to 1,500 ppm fluoride, which is effective for caries prevention in most patients. Higher concentrations are prescription products for elevated risk.

Question 42Provides oral hygiene instruction

A patient who grinds at night asks about oral hygiene. Which instruction is most relevant to protecting the dentition?

  1. Brush with a hard brush immediately after waking
  2. Discuss a protective occlusal appliance with the dentist Correct answer.
  3. Stop flossing to reduce sensitivity
  4. Increase acidic beverage intake

Explanation

Bruxism causes attrition and can worsen sensitivity, so a protective appliance prescribed by the dentist addresses the mechanical damage. Oral hygiene instruction should continue alongside, with attention to non-abrasive technique and desensitizing products.

Question 43Provides oral hygiene instruction

Which instruction best reduces the risk of fluorosis in a young child who uses fluoride toothpaste?

  1. Rinse with a fluoride mouthrinse daily
  2. Use a smear or rice-grain amount and supervise brushing Correct answer.
  3. Have the child swallow the paste to boost benefit
  4. Let the child use adult-strength paste freely

Explanation

Young children are at risk of fluorosis from swallowing toothpaste, so a small smear or rice-grain amount with supervision limits ingestion while retaining topical benefit. Children should be taught to spit rather than swallow.

Question 44Provides oral hygiene instruction

Which sequence best describes an effective plaque-control routine for a patient with generalized gingivitis?

  1. Brush with fluoride paste twice daily and clean interdentally once daily Correct answer.
  2. Floss only when food is felt between teeth
  3. Use mouthrinse alone twice daily
  4. Rinse with water, then brush once weekly

Explanation

Gingivitis control requires mechanical disruption of biofilm at least twice daily with fluoride paste plus daily interdental cleaning. Chemical rinses are adjuncts and cannot replace mechanical removal.

Question 45Provides oral hygiene instruction

A patient's bleeding on probing improves after two weeks of improved hygiene. What is the best interpretation for the patient?

  1. Bleeding reduction indicates the patient should brush harder
  2. The improvement means flossing is no longer needed
  3. Bleeding reduction shows the tissues are responding to plaque removal Correct answer.
  4. The disease is cured and hygiene can stop

Explanation

Gingival bleeding responds to plaque removal within roughly one to two weeks, so reduced bleeding is evidence that the hygiene routine is working. Patients should be encouraged to maintain rather than abandon the routine.

Question 46Provides oral hygiene instruction

Which statement about powered toothbrushes is most accurate for patient instruction?

  1. They remove plaque effectively with less manual dexterity demand Correct answer.
  2. They should be used with vigorous pressure
  3. They are contraindicated for all patients with crowns
  4. They eliminate the need for interdental cleaning

Explanation

Oscillating-rotating powered brushes remove plaque at least as well as manual brushing and reduce the dexterity burden, which helps patients with limited hand function. They do not replace interdental cleaning.

Question 47Provides oral hygiene instruction

A patient with xerostomia from medication asks how to reduce caries risk. Which advice is most appropriate?

  1. Avoid all fluoride products
  2. Stop brushing to avoid irritating dry tissue
  3. Sip water frequently and use fluoride products as advised Correct answer.
  4. Increase sugary lozenges to stimulate saliva

Explanation

Reduced salivary flow impairs buffering and remineralization, so frequent water sips, saliva substitutes, and topical fluoride support the dentition. Sugary products worsen caries risk even if they briefly stimulate saliva.

Question 48Provides oral hygiene instruction

Which statement about tongue cleaning is best supported for oral hygiene instruction?

  1. It is only useful for patients with dentures
  2. It should be performed with a hard-bristle brush on the gingiva
  3. It replaces toothbrushing on the lingual surfaces
  4. It can reduce tongue coating and contribute to halitosis control Correct answer.

Explanation

Mechanical tongue cleaning reduces coated tongue biofilm, which contributes to oral malodor, and is a useful adjunct to brushing and interdental cleaning. It does not substitute for cleaning tooth surfaces.

Question 49Provides oral hygiene instruction

A patient rinses vigorously with water immediately after brushing. Why should this be discouraged?

  1. It causes immediate gingival recession
  2. It increases the abrasive action of the paste
  3. It removes residual fluoride that supports remineralization Correct answer.
  4. It prevents the brush from reaching posterior teeth

Explanation

Rinsing with water right after brushing washes away residual fluoride from the paste, reducing the topical anticaries benefit. Advising patients to spit rather than rinse preserves fluoride at the tooth surface.

Question 50Provides oral hygiene instruction

A patient with orthodontic brackets asks for hygiene instruction. Which recommendation is most appropriate?

  1. Skip interdental cleaning until appliances are removed
  2. Avoid fluoride paste while appliances are present
  3. Brush only the bracket faces once daily
  4. Use an interdental brush and floss threader around wires and brackets Correct answer.

Explanation

Brackets and wires create plaque traps, so threaded floss, interdental brushes, and careful brushing around each bracket are needed to prevent demineralization. Fluoride paste remains important throughout treatment.