NATIONAL BOARD DENTAL HYGIENE
EXAMINATION PREP 5 | DENTAL HYGIENIST |
LATEST 2025-2026 QUESTION AND CORRECT
ANSWER WITH EXPLANATION WEST COAST
UNIVERSITY
Question 1
A 40-year-old patient presents with generalized 6–8 mm probing depths,
bleeding on probing, and radiographic horizontal bone loss extending to
the middle third of roots. What is the most appropriate diagnosis?
A. Stage II periodontitis
B. Stage III periodontitis
C. Stage IV periodontitis
D. Gingivitis
Correct Answer: B
Rationale: Moderate to severe attachment loss with bone extending to
mid-root indicates Stage III periodontitis.
Question 2
A patient reports spontaneous gingival bleeding, fatigue, and petechiae.
Clinical exam reveals enlarged gingiva and delayed healing. What is the
most likely systemic condition?
A. Diabetes mellitus
B. Leukemia
C. Asthma
D. Iron deficiency anemia
Correct Answer: B
Rationale: Leukemia commonly presents with gingival enlargement,
bleeding, and systemic symptoms.
Question 3
Which radiographic sign is most consistent with early periodontal disease?
,A. Loss of lamina dura
B. Root fracture
C. Periapical radiopacity
D. Hypercementosis
Correct Answer: A
Rationale: Loss of lamina dura is one of the earliest signs of periodontal
breakdown.
Question 4
A patient taking phenytoin presents with generalized gingival
enlargement. What is the best initial management?
A. Surgical gingivectomy
B. Improved plaque control and oral hygiene instruction
C. Immediate discontinuation of medication
D. Antibiotic therapy
Correct Answer: B
Rationale: Plaque control is first-line; medication changes require
physician consultation.
Question 5
Which microorganism is most associated with aggressive periodontitis?
A. Streptococcus mutans
B. Aggregatibacter actinomycetemcomitans
C. Lactobacillus acidophilus
D. Candida albicans
Correct Answer: B
Rationale: A. actinomycetemcomitans is strongly associated with
aggressive disease.
Question 6
, Which condition presents with necrotic interdental papillae, halitosis, and
severe pain?
A. Chronic gingivitis
B. Necrotizing periodontal disease
C. Periapical cyst
D. Fibroma
Correct Answer: B
Rationale: Classic triad of NPD includes necrosis, pain, and odor.
Question 7
Which anesthetic is most associated with methemoglobinemia?
A. Lidocaine
B. Prilocaine
C. Bupivacaine
D. Articaine
Correct Answer: B
Rationale: Prilocaine metabolites oxidize hemoglobin.
Question 8
A radiograph shows “floating teeth” appearance. What is the most likely
diagnosis?
A. Fibrous dysplasia
B. Langerhans cell histiocytosis
C. Chronic periodontitis
D. Osteomyelitis
Correct Answer: B
Rationale: LCH causes severe alveolar bone destruction.
Question 9
Which systemic disease most increases periodontal destruction risk?
EXAMINATION PREP 5 | DENTAL HYGIENIST |
LATEST 2025-2026 QUESTION AND CORRECT
ANSWER WITH EXPLANATION WEST COAST
UNIVERSITY
Question 1
A 40-year-old patient presents with generalized 6–8 mm probing depths,
bleeding on probing, and radiographic horizontal bone loss extending to
the middle third of roots. What is the most appropriate diagnosis?
A. Stage II periodontitis
B. Stage III periodontitis
C. Stage IV periodontitis
D. Gingivitis
Correct Answer: B
Rationale: Moderate to severe attachment loss with bone extending to
mid-root indicates Stage III periodontitis.
Question 2
A patient reports spontaneous gingival bleeding, fatigue, and petechiae.
Clinical exam reveals enlarged gingiva and delayed healing. What is the
most likely systemic condition?
A. Diabetes mellitus
B. Leukemia
C. Asthma
D. Iron deficiency anemia
Correct Answer: B
Rationale: Leukemia commonly presents with gingival enlargement,
bleeding, and systemic symptoms.
Question 3
Which radiographic sign is most consistent with early periodontal disease?
,A. Loss of lamina dura
B. Root fracture
C. Periapical radiopacity
D. Hypercementosis
Correct Answer: A
Rationale: Loss of lamina dura is one of the earliest signs of periodontal
breakdown.
Question 4
A patient taking phenytoin presents with generalized gingival
enlargement. What is the best initial management?
A. Surgical gingivectomy
B. Improved plaque control and oral hygiene instruction
C. Immediate discontinuation of medication
D. Antibiotic therapy
Correct Answer: B
Rationale: Plaque control is first-line; medication changes require
physician consultation.
Question 5
Which microorganism is most associated with aggressive periodontitis?
A. Streptococcus mutans
B. Aggregatibacter actinomycetemcomitans
C. Lactobacillus acidophilus
D. Candida albicans
Correct Answer: B
Rationale: A. actinomycetemcomitans is strongly associated with
aggressive disease.
Question 6
, Which condition presents with necrotic interdental papillae, halitosis, and
severe pain?
A. Chronic gingivitis
B. Necrotizing periodontal disease
C. Periapical cyst
D. Fibroma
Correct Answer: B
Rationale: Classic triad of NPD includes necrosis, pain, and odor.
Question 7
Which anesthetic is most associated with methemoglobinemia?
A. Lidocaine
B. Prilocaine
C. Bupivacaine
D. Articaine
Correct Answer: B
Rationale: Prilocaine metabolites oxidize hemoglobin.
Question 8
A radiograph shows “floating teeth” appearance. What is the most likely
diagnosis?
A. Fibrous dysplasia
B. Langerhans cell histiocytosis
C. Chronic periodontitis
D. Osteomyelitis
Correct Answer: B
Rationale: LCH causes severe alveolar bone destruction.
Question 9
Which systemic disease most increases periodontal destruction risk?
