NATIONAL BOARD DENTAL HYGIENE
EXAMINATION PREP 1 → DENTAL HYGIENIST
| LATEST 2025-2026 QUESTION AND CORRECT
ANSWER WITH EXPLANATION WEST COAST
UNIVERSITY
Question 1
A patient presents with bleeding on probing, intact attachment levels, and
no radiographic bone loss. What is the most appropriate diagnosis?
A. Stage I periodontitis
B. Stage II periodontitis
C. Gingivitis, plaque-induced
D. Necrotizing ulcerative gingivitis
Correct Answer: C
Rationale: Gingivitis presents with inflammation and bleeding without
attachment loss or bone loss.
Question 2
Which microorganism is most strongly associated with chronic
periodontitis?
A. Streptococcus mutans
B. Porphyromonas gingivalis
C. Candida albicans
D. Lactobacillus acidophilus
Correct Answer: B
Rationale: P. gingivalis is a key anaerobic pathogen linked to
periodontal destruction.
Question 3
A patient reports dry mouth after starting antihypertensive therapy.
Which class is most commonly associated with xerostomia?
,A. Calcium channel blockers
B. NSAIDs
C. Antacids
D. Antifungals
Correct Answer: A
Rationale: Calcium channel blockers frequently reduce salivary flow.
Question 4
Which radiographic feature is most consistent with early periodontal
disease?
A. Vertical bone loss
B. Widened periodontal ligament space
C. Periapical radiolucency
D. Root resorption
Correct Answer: B
Rationale: Early periodontal changes include PDL widening and loss of
lamina dura.
Question 5
A patient with type 1 diabetes presents with fruity breath odor. What is
the most likely systemic condition?
A. Hypoglycemia
B. Diabetic ketoacidosis
C. Hyperthyroidism
D. Addison’s disease
Correct Answer: B
Rationale: Fruity odor (acetone) is characteristic of ketoacidosis.
Question 6
Which local anesthetic has the longest duration of action?
, A. Lidocaine
B. Prilocaine
C. Bupivacaine
D. Mepivacaine
Correct Answer: C
Rationale: Bupivacaine has the longest duration among common dental
anesthetics.
Question 7
A patient on warfarin requires scaling and root planing. What is the most
important pre-procedure assessment?
A. Blood glucose level
B. INR value
C. Platelet count only
D. Liver enzyme levels
Correct Answer: B
Rationale: INR determines bleeding risk in anticoagulated patients.
Question 8
Which oral lesion is considered premalignant?
A. Aphthous ulcer
B. Leukoplakia
C. Herpetic lesion
D. Candidiasis
Correct Answer: B
Rationale: Leukoplakia carries malignant transformation risk.
Question 9
Which fluoride application method provides the highest concentration
exposure?
EXAMINATION PREP 1 → DENTAL HYGIENIST
| LATEST 2025-2026 QUESTION AND CORRECT
ANSWER WITH EXPLANATION WEST COAST
UNIVERSITY
Question 1
A patient presents with bleeding on probing, intact attachment levels, and
no radiographic bone loss. What is the most appropriate diagnosis?
A. Stage I periodontitis
B. Stage II periodontitis
C. Gingivitis, plaque-induced
D. Necrotizing ulcerative gingivitis
Correct Answer: C
Rationale: Gingivitis presents with inflammation and bleeding without
attachment loss or bone loss.
Question 2
Which microorganism is most strongly associated with chronic
periodontitis?
A. Streptococcus mutans
B. Porphyromonas gingivalis
C. Candida albicans
D. Lactobacillus acidophilus
Correct Answer: B
Rationale: P. gingivalis is a key anaerobic pathogen linked to
periodontal destruction.
Question 3
A patient reports dry mouth after starting antihypertensive therapy.
Which class is most commonly associated with xerostomia?
,A. Calcium channel blockers
B. NSAIDs
C. Antacids
D. Antifungals
Correct Answer: A
Rationale: Calcium channel blockers frequently reduce salivary flow.
Question 4
Which radiographic feature is most consistent with early periodontal
disease?
A. Vertical bone loss
B. Widened periodontal ligament space
C. Periapical radiolucency
D. Root resorption
Correct Answer: B
Rationale: Early periodontal changes include PDL widening and loss of
lamina dura.
Question 5
A patient with type 1 diabetes presents with fruity breath odor. What is
the most likely systemic condition?
A. Hypoglycemia
B. Diabetic ketoacidosis
C. Hyperthyroidism
D. Addison’s disease
Correct Answer: B
Rationale: Fruity odor (acetone) is characteristic of ketoacidosis.
Question 6
Which local anesthetic has the longest duration of action?
, A. Lidocaine
B. Prilocaine
C. Bupivacaine
D. Mepivacaine
Correct Answer: C
Rationale: Bupivacaine has the longest duration among common dental
anesthetics.
Question 7
A patient on warfarin requires scaling and root planing. What is the most
important pre-procedure assessment?
A. Blood glucose level
B. INR value
C. Platelet count only
D. Liver enzyme levels
Correct Answer: B
Rationale: INR determines bleeding risk in anticoagulated patients.
Question 8
Which oral lesion is considered premalignant?
A. Aphthous ulcer
B. Leukoplakia
C. Herpetic lesion
D. Candidiasis
Correct Answer: B
Rationale: Leukoplakia carries malignant transformation risk.
Question 9
Which fluoride application method provides the highest concentration
exposure?
