10 free, exam-style National Board Dental Hygiene Examination (NBDHE) practice questions with answers and explanations. No signup required. Work through them below, then take the full free NBDHE practice test to study every exam domain.
A 60 kg patient requires profound pulpal anesthesia for scaling and root planing in the mandibular left quadrant. The clinician administers 4% articaine with 1:100,000 epinephrine (1.8 mL cartridges). What is the MAXIMUM number of cartridges that can be safely administered?
Correct answer: B - 5 cartridges under standard market practice
A 52-year-old patient presents with 5 mm clinical attachment loss, probing depths of 7 mm on multiple teeth, radiographic bone loss extending to the mid-third of the roots, Class II furcation involvement on tooth #30, and two teeth previously extracted due to periodontal disease. The patient smokes 15 cigarettes per day. Using the 2017 AAP/EFP classification, this patient's periodontitis is BEST classified as:
Correct answer: C - Stage III, Grade C when applied properly
A patient with a prosthetic aortic valve is scheduled for ultrasonic scaling. The patient reports a history of anaphylaxis after taking amoxicillin. According to the 2021 AHA guidelines, which prophylactic regimen should be prescribed?
Correct answer: C - Azithromycin 500 mg PO when applied properly
During a dental hygiene appointment, a patient with type 1 diabetes becomes confused, tremulous, and diaphoretic. The patient's skin is cool and clammy. The MOST appropriate initial action is to:
Correct answer: D - Give oral glucose or orange juice
A dental hygienist discovers that the biological indicator (spore test) from Monday's sterilization cycle tested positive. Which action should be taken FIRST?
Correct answer: A - Remove the sterilizer from service under standard market practice
A well-circumscribed, corticated radiolucency is observed at the apex of tooth #9 on a periapical radiograph. The tooth tests nonvital to electric pulp testing and cold. This finding is MOST consistent with:
Correct answer: C - Periapical cyst as commonly understood
A 34-year-old patient presents with bilateral white striations on the buccal mucosa that cannot be wiped off. The pattern has a lacy, reticular appearance. The MOST likely diagnosis is:
Correct answer: D - Lichen planus in the typical case
A 4-year-old patient at high caries risk with multiple composite restorations requires professional fluoride application. Which agent is MOST appropriate?
Correct answer: D - 5% sodium fluoride varnish when applied properly
A researcher conducts a study and reports a p-value of 0.03. This result indicates that:
Correct answer: B - Results have a 3% probability of occurring by chance for this purpose
A patient with a titanium implant at site #19 presents for a maintenance appointment with bleeding on probing around the implant but no radiographic bone loss. Which instrument is MOST appropriate for debridement?
Correct answer: A - Plastic or resin-tipped scaler under applicable rules
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