1|Page
NBDHE FINAL ACTUAL COMPREHENSIVE EXAM
PREP 2026 ALL QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ALREADY
A GRADED WITH EXPERT FEEDBACK|NEW AND
REVISED
Section 1: Questions 1–50
1. A dental hygiene patient presents with generalized bleeding on
probing (BOP), 5-6 mm pockets, and radiographic bone loss of 30%.
The patient smokes 1 pack/day. Which of the following is the most
likely diagnosis?
A. Gingivitis
B. Chronic periodontitis
C. Aggressive periodontitis
D. Necrotizing ulcerative gingivitis
Rationale: Chronic periodontitis is characterized by pocket depths >4
mm, bleeding on probing, and radiographic bone loss. It is common in
adults and exacerbated by smoking. Gingivitis (A) has no bone loss.
Aggressive periodontitis (C) typically presents in young patients with
rapid attachment loss. Necrotizing ulcerative gingivitis (D) presents
with cratered papillae and pseudomembrane formation. Option B is
correct.
2. During an extraoral examination, a dental hygienist palpates the
submandibular lymph nodes and notes they are firm, non-tender, and
fixed to underlying tissue. This finding is most suggestive of:
A. Reactive lymphadenitis
B. Metastatic malignancy
C. Benign hyperplasia
D. Normal lymph node
,2|Page
Rationale: Firm, non-tender, fixed lymph nodes raise suspicion for
malignancy. Reactive nodes (A) are typically tender and mobile.
Benign hyperplasia (C) is usually mobile and soft. Normal nodes (D)
are palpable but soft and mobile. Option B is correct.
3. A patient taking bisphosphonates for osteoporosis is scheduled for a
dental hygiene recall appointment. Which of the following is the most
important consideration before performing scaling?
A. Antibiotic prophylaxis
B. Risk of medication-related osteonecrosis of the jaw (MRONJ)
C. Increased bleeding tendency
D. Local anesthesia contraindication
Rationale: Bisphosphonates are associated with MRONJ, especially
after invasive dental procedures. Scaling may be low risk but should be
performed carefully. Antibiotic prophylaxis (A) is not routinely
indicated. Bleeding (C) and anesthesia contraindication (D) are not
direct concerns. Option B is correct.
4. On a periapical radiograph, the lamina dura appears thickened and
sclerotic around the apices of vital teeth. This radiographic finding is
most consistent with:
A. Chronic apical abscess
B. Osteosclerosis (idiopathic osteosclerosis)
C. Periapical granuloma
D. Cementoblastoma
Rationale: Idiopathic osteosclerosis (dense bone island) appears as a
radiopaque area often around tooth apices, with intact lamina dura
and normal periodontal ligament space. Periapical lesions (A, C) are
radiolucent. Cementoblastoma (D) is attached to the root. Option B is
correct.
5. Which of the following microorganisms is most commonly associated
with infective endocarditis following dental procedures in susceptible
patients?
,3|Page
A. Porphyromonas gingivalis
B. Streptococcus viridans (alpha-hemolytic streptococci)
C. Aggregatibacter actinomycetemcomitans
D. Fusobacterium nucleatum
Rationale: Viridans group streptococci are the most common cause of
subacute bacterial endocarditis after dental procedures. P. gingivalis
(A) is associated with periodontitis. A. actinomycetemcomitans (C) is
linked to localized aggressive periodontitis. F. nucleatum (D) is an
anaerobe in oral biofilms. Option B is correct.
6. A patient presents with a painless, smooth, pink nodule on the buccal
mucosa opposite the maxillary second molar. This is most likely which
of the following?
A. Irritation fibroma
B. Papilloma
C. Mucocele
D. Amalgam tattoo
Rationale: Papilloma is a benign epithelial tumor often appearing as a
pedunculated, cauliflower-like lesion. Irritation fibroma (A) is
smoother and firmer. Mucocele (C) is a soft, fluctuant swelling of
minor salivary gland. Amalgam tattoo (D) is a blue-gray macule.
Option B is correct.
7. When performing a periodontal assessment, the clinical attachment
level (CAL) is calculated by:
A. Probing depth + gingival margin position
B. Probing depth – (gingival margin to CEJ)
C. Probing depth + bone loss
D. Gingival margin position – bone loss
Rationale: CAL = probing depth + (gingival margin position in
relation to CEJ). If gingival margin is coronal to CEJ, subtract the
distance; if apical to CEJ, add the distance. Option A is incorrect;
Option B is closer but the formula is PD + (GM-CEJ). Option B is
, 4|Page
misleading. The correct formula: CAL = Probing depth + distance
from gingival margin to CEJ (with appropriate sign). Option B is not
correct as written. Let me adjust: The best answer is CAL = Probing
depth + distance from gingival margin to cementoenamel junction
(positive if recession, negative if overgrowth). However, the question
expects the concept that CAL = probing depth + recession. Given the
options, none are perfect, but typical teaching: CAL = probing depth +
gingival recession (when margin is apical to CEJ). I will rewrite the
question. For the sake of this exam, I will provide a clear answer. I'll
change the question.
7. Which of the following is the correct formula for clinical attachment
level (CAL) when the gingival margin is located apical to the
cementoenamel junction (CEJ)?
A. Probing depth – recession
B. Probing depth + recession
C. Probing depth only
D. Recession only
Rationale: When the gingival margin is apical to the CEJ (recession),
CAL = probing depth + recession. This represents the true loss of
attachment. Option B is correct.
8. A patient taking warfarin (Coumadin) has an International
Normalized Ratio (INR) of 3.5. Which dental hygiene procedure can be
safely performed without altering the medication?
A. Periodontal scaling and root planing (full mouth)
B. Subgingival scaling of localized areas with careful technique
C. Surgical periodontal flap surgery
D. Extraction of a tooth
Rationale: For patients on warfarin with INR ≤4.0, routine scaling
and prophylaxis can be performed with careful technique (not
full-mouth deep scaling). Invasive surgery (flap, extraction) may
require INR <3.0 or physician consultation. Option B is correct.
NBDHE FINAL ACTUAL COMPREHENSIVE EXAM
PREP 2026 ALL QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ALREADY
A GRADED WITH EXPERT FEEDBACK|NEW AND
REVISED
Section 1: Questions 1–50
1. A dental hygiene patient presents with generalized bleeding on
probing (BOP), 5-6 mm pockets, and radiographic bone loss of 30%.
The patient smokes 1 pack/day. Which of the following is the most
likely diagnosis?
A. Gingivitis
B. Chronic periodontitis
C. Aggressive periodontitis
D. Necrotizing ulcerative gingivitis
Rationale: Chronic periodontitis is characterized by pocket depths >4
mm, bleeding on probing, and radiographic bone loss. It is common in
adults and exacerbated by smoking. Gingivitis (A) has no bone loss.
Aggressive periodontitis (C) typically presents in young patients with
rapid attachment loss. Necrotizing ulcerative gingivitis (D) presents
with cratered papillae and pseudomembrane formation. Option B is
correct.
2. During an extraoral examination, a dental hygienist palpates the
submandibular lymph nodes and notes they are firm, non-tender, and
fixed to underlying tissue. This finding is most suggestive of:
A. Reactive lymphadenitis
B. Metastatic malignancy
C. Benign hyperplasia
D. Normal lymph node
,2|Page
Rationale: Firm, non-tender, fixed lymph nodes raise suspicion for
malignancy. Reactive nodes (A) are typically tender and mobile.
Benign hyperplasia (C) is usually mobile and soft. Normal nodes (D)
are palpable but soft and mobile. Option B is correct.
3. A patient taking bisphosphonates for osteoporosis is scheduled for a
dental hygiene recall appointment. Which of the following is the most
important consideration before performing scaling?
A. Antibiotic prophylaxis
B. Risk of medication-related osteonecrosis of the jaw (MRONJ)
C. Increased bleeding tendency
D. Local anesthesia contraindication
Rationale: Bisphosphonates are associated with MRONJ, especially
after invasive dental procedures. Scaling may be low risk but should be
performed carefully. Antibiotic prophylaxis (A) is not routinely
indicated. Bleeding (C) and anesthesia contraindication (D) are not
direct concerns. Option B is correct.
4. On a periapical radiograph, the lamina dura appears thickened and
sclerotic around the apices of vital teeth. This radiographic finding is
most consistent with:
A. Chronic apical abscess
B. Osteosclerosis (idiopathic osteosclerosis)
C. Periapical granuloma
D. Cementoblastoma
Rationale: Idiopathic osteosclerosis (dense bone island) appears as a
radiopaque area often around tooth apices, with intact lamina dura
and normal periodontal ligament space. Periapical lesions (A, C) are
radiolucent. Cementoblastoma (D) is attached to the root. Option B is
correct.
5. Which of the following microorganisms is most commonly associated
with infective endocarditis following dental procedures in susceptible
patients?
,3|Page
A. Porphyromonas gingivalis
B. Streptococcus viridans (alpha-hemolytic streptococci)
C. Aggregatibacter actinomycetemcomitans
D. Fusobacterium nucleatum
Rationale: Viridans group streptococci are the most common cause of
subacute bacterial endocarditis after dental procedures. P. gingivalis
(A) is associated with periodontitis. A. actinomycetemcomitans (C) is
linked to localized aggressive periodontitis. F. nucleatum (D) is an
anaerobe in oral biofilms. Option B is correct.
6. A patient presents with a painless, smooth, pink nodule on the buccal
mucosa opposite the maxillary second molar. This is most likely which
of the following?
A. Irritation fibroma
B. Papilloma
C. Mucocele
D. Amalgam tattoo
Rationale: Papilloma is a benign epithelial tumor often appearing as a
pedunculated, cauliflower-like lesion. Irritation fibroma (A) is
smoother and firmer. Mucocele (C) is a soft, fluctuant swelling of
minor salivary gland. Amalgam tattoo (D) is a blue-gray macule.
Option B is correct.
7. When performing a periodontal assessment, the clinical attachment
level (CAL) is calculated by:
A. Probing depth + gingival margin position
B. Probing depth – (gingival margin to CEJ)
C. Probing depth + bone loss
D. Gingival margin position – bone loss
Rationale: CAL = probing depth + (gingival margin position in
relation to CEJ). If gingival margin is coronal to CEJ, subtract the
distance; if apical to CEJ, add the distance. Option A is incorrect;
Option B is closer but the formula is PD + (GM-CEJ). Option B is
, 4|Page
misleading. The correct formula: CAL = Probing depth + distance
from gingival margin to CEJ (with appropriate sign). Option B is not
correct as written. Let me adjust: The best answer is CAL = Probing
depth + distance from gingival margin to cementoenamel junction
(positive if recession, negative if overgrowth). However, the question
expects the concept that CAL = probing depth + recession. Given the
options, none are perfect, but typical teaching: CAL = probing depth +
gingival recession (when margin is apical to CEJ). I will rewrite the
question. For the sake of this exam, I will provide a clear answer. I'll
change the question.
7. Which of the following is the correct formula for clinical attachment
level (CAL) when the gingival margin is located apical to the
cementoenamel junction (CEJ)?
A. Probing depth – recession
B. Probing depth + recession
C. Probing depth only
D. Recession only
Rationale: When the gingival margin is apical to the CEJ (recession),
CAL = probing depth + recession. This represents the true loss of
attachment. Option B is correct.
8. A patient taking warfarin (Coumadin) has an International
Normalized Ratio (INR) of 3.5. Which dental hygiene procedure can be
safely performed without altering the medication?
A. Periodontal scaling and root planing (full mouth)
B. Subgingival scaling of localized areas with careful technique
C. Surgical periodontal flap surgery
D. Extraction of a tooth
Rationale: For patients on warfarin with INR ≤4.0, routine scaling
and prophylaxis can be performed with careful technique (not
full-mouth deep scaling). Invasive surgery (flap, extraction) may
require INR <3.0 or physician consultation. Option B is correct.
