DANB practice test for the CDA: GC and ICE questions

During the extraoral exam, the assistant palpates a lymph node that should be reported to the dentist as MOST suspicious. It is:

Pick the option you would mark on test day. The choice stays fixed, and every option then explains itself.

1. Tender during a sore throat

   Tenderness during a throat infection points to a reactive node responding to infection, which usually settles.
2. Hard, fixed and painless

   A hard, fixed, painless node is the pattern that raises concern for malignancy and needs prompt evaluation by the dentist.
3. Soft, mobile and tender

   Soft, movable, tender nodes suggest inflammation or infection rather than a tumor.
4. Small, mobile and nontender

   Small, movable, nontender nodes are common in healthy adults and are usually not a concern.

Nitrous oxide–oxygen sedation is generally avoided in a patient with:

1. Severe nasal congestion

   Nitrous oxide is inhaled through a nasal hood, so a patient who cannot breathe through the nose will not receive an effective dose.
2. Controlled hypertension

   Controlled blood pressure is not a reason to withhold nitrous oxide, which is delivered with plenty of oxygen.
3. Mild dental anxiety

   Mild anxiety is a typical reason to offer nitrous oxide sedation.
4. A strong gag reflex

   Nitrous oxide is often used to calm a strong gag reflex rather than being avoided because of it.

A patient has type 2 diabetes controlled with metformin and mild hypertension controlled with medication. His ASA physical status is:

1. ASA I

   ASA I describes a healthy patient with no systemic disease, not someone taking medication for two chronic conditions.
2. ASA II

   Mild systemic disease that is well controlled, such as treated type 2 diabetes and treated hypertension, fits ASA II.
3. ASA III

   ASA III is for severe or poorly controlled disease that limits activity, which this patient does not have.
4. ASA IV

   ASA IV is severe disease that is a constant threat to life, far beyond controlled diabetes and blood pressure.

Which toothbrushing technique is usually taught to young children because it is easy to learn?

1. Fones technique

   The Fones method uses large circular strokes with the teeth together, a simple motion young children can manage.
2. Bass technique

   The Bass method angles the bristles into the sulcus with short vibrating strokes, which takes dexterity young children lack.
3. Charters technique

   Charters angles the bristles toward the biting surface for cleaning around appliances or after periodontal surgery, which is too exacting for young children.
4. Stillman technique

   Stillman places the bristles partly on the gingiva for stimulation and is taught to adults with recession.

When teaching flossing, the patient should be told to:

1. Snap it down onto the gum

   Snapping floss down onto the gum drives it into the papilla and causes floss cuts.
2. Curve it in a C at each tooth

   Wrapping the floss around each tooth in a C shape and sliding it just below the gumline cleans the proximal surface instead of only the contact.
3. Saw it back and forth along the gums

   A sawing motion only helps the floss pass the contact; sawing along the gumline cuts the tissue.
4. Skip any tight contacts

   A tight contact is eased through with a gentle back-and-forth motion, not skipped; skipping leaves plaque between those teeth.

When passing extraction forceps for a maxillary molar, the beaks should point:

1. Downward, toward the floor

   Beaks pointing downward, toward the floor, is the position for mandibular teeth, not for an upper molar.
2. Upward, toward the ceiling

   Forceps are passed in the position of use; for maxillary teeth the beaks point upward so the dentist can seat them without turning the instrument.
3. Sideways, toward the assistant

   Beaks aimed back at the assistant are in no usable position and put the assistant's hand at risk.
4. Toward the patient's chin

   Beaks aimed at the chin point away from the upper arch, so the dentist would have to turn the instrument before use.

Which instrument transfers amalgam from the well to the preparation?

1. Amalgam carrier

   The carrier picks up triturated amalgam from the well and releases it into the preparation in small increments.
2. Plastic instrument

   A plastic instrument places and shapes composite, cement and temporary material rather than carrying amalgam.
3. Amalgam condenser

   The condenser packs amalgam once it is in the preparation; the carrier is what delivers it there.
4. Ball-ended burnisher

   A ball-ended burnisher smooths and shapes amalgam after condensation; it does not transport material.

A dental dam is placed for an MO restoration on #29. The clamp is usually placed on tooth:

1. #27

   #27 is the canine, two teeth mesial, and a clamp there would not hold the dam behind the working area.
2. #28

   #28 lies mesial to the working tooth; the anchor is placed on the distal side.
3. #29

   Clamping #29 itself puts the clamp over the tooth being prepared and in the operator's way.
4. #30

   The clamp usually goes one tooth distal to the tooth being treated, so for #29 the anchor is the first molar, #30.

The operator holds the dental dam clamp forceps with which grasp?

1. Standard pen grasp

   A standard pen grasp suits mirrors and light instruments and cannot spread a clamp.
2. Modified pen grasp

   The modified pen grasp is for hand instruments such as explorers and scalers, not for forceps that must be squeezed open.
3. Palm grasp

   Dental dam clamp forceps are held in the palm with the fingers wrapped around the handle so the hand can squeeze them open and control the clamp.
4. Thumb-to-nose grasp

   The thumb-to-nose grasp is a reinforced hold for maxillary work with a handpiece or scaler, not for clamp forceps.

Swelling appears on the patient's cheek within seconds of a posterior superior alveolar injection. This is most likely a:

1. Hematoma

   A hematoma forms when the needle nicks the pterygoid venous plexus during a PSA injection, and the bleeding shows as swelling within seconds.
2. Allergic reaction

   True allergy to an amide anesthetic is rare and shows as hives, itching or breathing trouble rather than one localized swelling at the site.
3. Paresthesia

   Paresthesia is persistent numbness or tingling after nerve injury and produces no swelling.
4. Trismus

   Trismus is limited opening from muscle injury and develops over hours to days, not as swelling within seconds.

Which commonly used dental anesthetic belongs to the ester group, which causes more allergic reactions?

1. Mepivacaine

   Mepivacaine is an amide often chosen in a plain form without a vasoconstrictor; it is not an ester.
2. Benzocaine

   Benzocaine is an ester-type topical anesthetic, and esters break down to PABA, which is behind most allergic reactions to local anesthetics.
3. Prilocaine

   Prilocaine is an amide; its known concern is methemoglobinemia, not ester allergy.
4. Lidocaine

   Lidocaine is the most widely used amide injectable and rarely causes true allergy.

When a Tofflemire matrix is assembled for a Class II amalgam on #30, the diagonal slot of the retainer faces:

1. Toward the occlusal

   A slot facing the occlusal turns the band upside down, with its wider edge at the gumline.
2. Toward the lingual

   The retainer rests on the buccal surface, and the slot is oriented toward the gingiva, not turned to the lingual.
3. Away from the band

   The slot holds the band ends, so it cannot face away from the band and still secure it.
4. Toward the gingiva

   With the diagonal slot facing the gingiva, the band's smaller edge sits at the gumline and the retainer stays clear of the occlusal surface.

To block the parotid duct while #3 is being restored, a cotton roll is placed in the:

1. Floor of the mouth, lingually

   The floor of the mouth is where the submandibular and sublingual ducts drain, which matters for mandibular work.
2. Maxillary buccal vestibule

   Stensen's duct opens on the cheek opposite the maxillary second molar, so a roll in the upper buccal vestibule absorbs its flow.
3. Mandibular lingual sulcus

   The mandibular lingual area collects sublingual and submandibular saliva, not parotid secretion.
4. Center of the hard palate

   No major salivary duct opens on the hard palate, so a roll there does nothing for parotid flow.

The dentist asks for zinc phosphate at luting consistency to cement a crown. The mix is correct when, as the spatula is lifted from the slab, it:

1. Strings out about 1 inch

   At luting consistency, zinc phosphate is creamy and follows the spatula in a thread about an inch long before breaking.
2. Rolls into a putty ball

   A putty that rolls into a ball is base consistency, used under restorations, and too thick to seat a crown.
3. Breaks off with no string

   No string at all means the mix is too thick for cementation, and the crown will not seat fully.
4. Strings out about 4 inches

   A thread around 4 inches long means the mix is too thin and will set weak.

Zinc phosphate cement is mixed over a wide area of a cool glass slab because:

1. Its powder is hygroscopic

   Moisture sensitivity concerns the liquid, which is kept capped; whether the powder is hygroscopic has nothing to do with spreading the mix over a wide area.
2. It reacts to curing light

   Zinc phosphate sets by an acid-base reaction and is not light-activated.
3. Its setting gives off heat

   The setting reaction of zinc phosphate is exothermic; spreading the mix over a wide area of a cool slab carries that heat off and lengthens working time.
4. It bonds to glass

   Zinc phosphate does not bond to a clean glass slab, and it retains crowns mechanically rather than by chemical bonding.

For a three-step etch-and-rinse bond under a composite restoration, which order of steps is correct?

1. Etch, rinse, primer, adhesive

   The acid etch is rinsed off first; the primer then wets the demineralized dentin, and the adhesive resin goes on last, ready for the composite.
2. Etch, primer, rinse, adhesive

   Rinsing after the primer washes the primer away, so the adhesive ends up on unprimed dentin.
3. Primer, etch, rinse, adhesive

   Primer applied before etching is stripped by the acid and the rinse, so it no longer prepares the dentin.
4. Etch, rinse, adhesive, primer

   Adhesive placed before the primer meets dentin that has not been primed, and primer over the adhesive weakens the bond to the composite.

Why should an operator avoid adjusting eyewear or hair while wearing contaminated gloves?

1. It tears the glove fingertips

   Adjusting glasses does not damage gloves; the concern is moving contaminated fluid, not glove wear.
2. It fogs the protective eyewear

   Fogging of the eyewear comes from breath and mask fit, not from handling the frames.
3. It breaks the seal of the face mask

   Touching eyewear or hair need not disturb the mask; the problem is the contamination left behind.
4. It moves saliva toward the eyes

   Gloves that carry saliva or blood leave those fluids on eyewear and hair right next to the eyes, nose and mouth, where they can reach mucous membranes.

A reusable clinic gown worn during patient care should be changed:

1. Weekly, unless it is torn

   A weekly change leaves a soiled gown in use for days; soiling, not only tearing, calls for a change.
2. Only after surgery

   Gowns become soiled during routine care too, so changing them only after surgery is not enough.
3. Daily, or when visibly soiled

   A reusable gown is changed at least daily and sooner when it becomes visibly soiled or wet with fluids.
4. Once a month

   Changing once a month keeps a contaminated gown in use long after it carries visible soil.

According to CDC, can an extracted tooth be returned to the patient who asks for it?

1. No, it is regulated waste

   Teeth headed for disposal are handled as regulated waste, but that status does not bar returning a tooth the patient asks for.
2. Yes, after 2 weeks in formalin

   Formalin immersion prepares amalgam-containing teeth for educational use; CDC sets no such step before a tooth goes back to its owner.
3. Yes, in a red sharps container

   A sharps container is a disposal device, and CDC attaches no container condition to returning a tooth to the patient.
4. Yes, it goes home on request

   CDC states that extracted teeth can be returned to patients on request; once the tooth is in the patient's hands, OSHA's bloodborne pathogens provisions no longer apply to it.

Which dental unit component is designed to keep oral fluids from being drawn back into the handpiece waterline?

1. An amalgam separator

   An amalgam separator removes amalgam particles from wastewater before it reaches the sewer.
2. An anti-retraction valve

   Anti-retraction valves keep oral fluids from being pulled back into handpieces and waterlines when the handpiece stops.
3. A vacuum line trap

   The trap catches solids in the evacuation system and has nothing to do with the water supplied to handpieces.
4. An independent water reservoir

   A separate bottle changes where unit water comes from but does not stop suck-back at the handpiece.

A dental assistant inadvertently leaves an alginate impression submerged in a disinfectant solution for several hours. What is the most likely consequence?

1. Slight shrinkage of the impression

   Shrinkage (syneresis) happens when alginate is left out to dry in air, not when it sits in liquid.
2. Cracking of the material

   Cracking is not how a wet hydrocolloid responds; it takes up water and swells.
3. Better disinfection, no change

   Extra soaking gives no better disinfection; past the labeled contact time it only damages the impression.
4. Swelling and dimensional distortion

   Alginate is mostly water and absorbs more from a soaking solution (imbibition), so hours of immersion swell and distort the impression.

Which packaging is appropriate for instruments processed in a steam autoclave?

1. Closed, unvented metal containers

   Closed containers without vents shut steam out; only cassettes or containers designed for steam allow it in.
2. Wrapping in aluminum foil

   Foil blocks steam penetration, so instruments wrapped in it are not reliably sterilized.
3. Sealed glass jars with lids

   A sealed glass jar keeps steam from contacting the instruments inside, so they are not sterilized.
4. Peel pouches of paper and plastic

   Paper and plastic peel pouches cleared for steam let steam reach the instruments and then keep them sterile once the cycle ends.

The tank of the ultrasonic unit is empty. Which product should it be refilled with?

1. Dish soap in warm tap water

   Dish soap foams, which dampens cavitation, and it is not made to lift dried blood and debris from instruments.
2. Diluted surface disinfectant

   Surface disinfectants are labeled for environmental surfaces, not as a cleaning solution in an ultrasonic unit.
3. Enzymatic instrument cleaner

   An enzymatic instrument cleaner labeled for ultrasonic use is made to work with cavitation and break down bioburden without heavy foaming.
4. Sterile normal saline

   Saline leaves salt behind and promotes corrosion and pitting of stainless steel instruments.

Under OSHA, contaminated reusable protective gowns worn by dental assistants are laundered by:

1. The employee at home with other clothing

   Home laundering carries contamination into the household and is not allowed for contaminated PPE.
2. The employee, who is reimbursed monthly

   Paying the employee back does not shift the duty; the employer must arrange the laundering.
3. The employer, at no cost to the employee

   OSHA's bloodborne pathogens standard makes the employer responsible for cleaning, laundering or disposing of PPE at no cost to the worker, in-house or through a laundry service.
4. Any public laundromat near the office

   A public laundromat is not set up to receive contaminated laundry bagged and labeled under OSHA's handling rules.

An assistant starts HIV post-exposure prophylaxis 2 hours after a needlestick from a source patient with HIV. Under current U.S. PHS guidance, PEP is taken for:

1. 28 days

   Current U.S. PHS guidance runs HIV post-exposure prophylaxis for 28 days, started as soon as possible after the exposure.
2. 72 hours

   72 hours is the outer window usually cited for starting PEP, not the length of the course.
3. 12 weeks

   Twelve weeks is far longer than the course; the medications are stopped after four weeks.
4. 6 weeks

   Six weeks is a common point for follow-up HIV testing, not the duration of the medication.

After an extraction, the patient is told not to use a straw for 24 hours because:

1. Straws carry bacteria inward

   A clean straw does not introduce bacteria; the risk comes from the suction it creates.
2. Cold liquids slow the healing

   Cold liquids are fine after an extraction and do not slow healing; temperature is not why straws are avoided.
3. Suction can dislodge the clot

   Sucking through a straw creates negative pressure in the mouth that can pull the clot from the socket and lead to a dry socket.
4. Sipping makes swelling worse

   Swelling depends on the surgery and is managed with cold compresses; sipping through a straw does not increase it.

Which measure most effectively reduces aerosols and spatter during a high-speed preparation?

1. A saliva ejector

   A saliva ejector moves too little air to capture handpiece spray.
2. Dental dam with HVE

   A dam keeps saliva and blood out of the field, and the high-volume evacuator captures spray at its source; together they cut aerosol and spatter the most.
3. More handpiece water spray

   Extra coolant water increases the amount of spray produced rather than reducing it.
4. A preprocedural rinse

   A rinse briefly lowers oral bacterial counts but removes nothing from the air, and CDC lists its infection-prevention value as unresolved.

At the end of the day, the HVE and saliva ejector lines should be:

1. Flushed with household bleach

   Bleach and chlorine line cleaners can release mercury from amalgam in the lines, which the EPA effluent rule prohibits.
2. Left dry to prevent biofilm

   Leaving the lines unflushed lets debris and biofilm accumulate; drying alone does not clean them.
3. Heat-sterilized with the handpieces

   Vacuum hoses and lines are part of the unit and cannot go into a sterilizer; they are cleaned in place.
4. Flushed with an evacuation cleaner

   At day's end the HVE and saliva ejector lines are flushed with a cleaner made for evacuation systems, which clears debris and limits buildup in the lines.

Which items are better sterilized with dry heat than with steam, to keep them from rusting?

1. Carbon steel burs and pliers

   Carbon steel corrodes in the moisture of a steam cycle, so carbon steel burs and pliers are processed with dry heat or unsaturated chemical vapor to avoid rust.
2. Stainless steel mirrors and explorers

   Stainless steel mirrors and explorers resist corrosion and go through steam without rusting.
3. Plastic saliva ejectors and HVE tips

   Plastic saliva ejectors and HVE tips are disposable or heat-sensitive, and dry-heat temperatures would melt them.
4. Latex gloves and rubber dams

   Latex gloves and dam material are single-use and are not sterilized for reuse; dry heat would destroy them.

Medical records for a dental employee with occupational exposure to blood must be kept for:

1. 3 years from the date of any exposure

   Three years is the retention period for bloodborne pathogens training records, not for employee medical records.
2. 5 years after the employee leaves

   Five years after leaving falls far short of the 30-year requirement for exposure medical records.
3. The length of employment plus 30 years

   OSHA requires the employer to keep each exposed employee's medical record for the duration of employment plus 30 years, because bloodborne infections can surface long after an exposure.
4. As long as the employee holds a credential

   Retention is tied to employment, not to whether the person stays certified or licensed.